POROUS MATERIALS FOR SOLID PHASE EXTRACTION AND CHROMATOGRAPHY AND PROCESSES FOR PREPARATION AND USE THEREOF

BACKGROUND OF THE INVENTION

Solid phase extraction (SPE) is a chromatographic technique that is widely used, e.g., for preconcentration and cleanup of analytical samples, for purification of various chemicals, and for removal of toxic or valuable substances from aqueous solutions. SPE is usually performed using a column or cartridge containing an appropriate material or sorbent. SPE procedures have been developed using sorbents that can interact with analytes by hydrophobic, ion-exchange, chelation, sorption, and other mechanisms, to bind and remove the analytes from fluids.

Because different SPE applications can require different sorbents, there is a need for sorbents with novel properties that have unique selectivities. These include superior wetting characteristics, selective capture of analytes of interest, and non-retention of interfering analytes. Sorbents comprising porous particles having the aforementioned properties are described in WO 99/64480 and in U.S. Pat. No. 6,322,695B1.

The most common materials currently used are a co-polymer of divinylbenzene and N-vinyl pyrrolidinone with an average pore diameter of 73-89 Å. The pore size of this material is however too restrictive for samples of biological materials.

There remains a need for SPE materials with larger average pore diameters which maintain nitrogen content in the materials as well as particle morphology.

SUMMARY OF THE INVENTION

The invention provides novel porous materials that are useful in chromatographic processes, e.g., solid phase extraction, and that provide a number of advantages. Such advantages include superior wetting characteristics, selective capture of analytes of interest, and non-retention of interfering analytes. The invention advantageously provides novel porous materials having a large percentage of larger pores (i.e. wide pores). The invention advantageously provides novel porous materials that overcome the problems of SPE of biological samples.

In one aspect, the invention provides a porous material comprising a copolymer of at least one hydrophobic monomer and at least one hydrophilic monomer, wherein more than 10% of the Barret-Joyner-Halenda (BJH) surface area of the porous material is contributed by pores that have a diameter greater than or equal to 200 Å. In certain aspects, the BJH surface area and pore diameter are determined using a nitrogen gas adsorption desorption isotherm at 77.3K.

In another aspect, the invention provides a porous material comprising a copolymer of at least one hydrophobic monomer and at least one hydrophilic monomer, wherein said material has a median pore diameter as measured by inverse size exclusion chromatography of about 100 Å to about 1000 Å.

In yet another aspect, the invention provides a porous material comprising a copolymer of at least one hydrophobic monomer and at least one hydrophilic monomer.

In certain embodiments the at least one hydrophilic monomer is a monomer having a log P value of less than 1.5. In certain embodiments the hydrophilic monomer is a monomer having a log P value of less than 1.0. In certain embodiments the hydrophilic monomer is a monomer having a log P value of less than 0.5. In certain embodiments the hydrophilic monomer is a monomer having a log P value of less than 0.0.

In certain embodiments, at least one of the hydrophilic monomer is a monomer having the formula:

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wherein n is an integer from 1-3; or wherein the hydrophilic monomers is a monomer of the formula:

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wherein R₁is selected from C₁-C₆alkylene, C₂-C₆alkenylene, C₂-C₆alkynylene, C₆-C₁₈arylene groups, and wherein R₂is selected from H, C₁-C₆alkylene, C₂-C₆alkenylene, C₂-C₆alkynylene, C₆-C₁₈arylene groups.

In certain embodiments, the hydrophilic monomer of the porous material of the invention is N-vinylcaprolactam,

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In certain embodiments, said hydrophilic monomer of the porous material of the invention is not N-vinylpyrrolidone,

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In certain embodiments the hydrophilic monomer is selected from n-vinyl pyrrolidone, acrylonitrile, 4-vinyl pyridine, or boronic-acid-containing monomers, among others.

In certain embodiments, said hydrophilic monomer of the porous material of the invention is further substituted by at least one haloalkyl group.

In certain embodiments, the at least one hydrophobic monomer is divinylbenzene and/or styrene.

In certain embodiments, the at least one hydrophobic monomer is further substituted by at least one haloalkyl group.

In certain embodiments, said copolymer of the porous material of the invention is a poly(divinylbenzene-co-N-vinylcaprolactam).

In certain embodiments, the porous material of the invention comprises a porous particle that comprises said copolymer.

In certain embodiments, the porous material of the invention comprises a porous monolith that comprises said copolymer.

In another aspect, the invention also provides solid phase extraction and chromatography materials comprising porous materials of the invention.

In yet another aspect, the invention provides a separation device comprising a porous material of the invention. In a related aspect, the invention provides a solid phase extraction cartridge comprising a porous material according to the invention.

In yet another aspect, the invention also provides a method for removing or isolating a component from a mixture. The method comprises contacting the mixture with a chromatographic material comprising the porous material according to the invention, to thereby remove or isolate the component from the mixture.

In another aspect, the invention provides a method for isolating a component in a mixture or determining the level of a component in a mixture. The method comprises contacting the mixture with a chromatographic material comprising a porous material according to the invention under conditions that allow for sorption of the component onto the porous material; washing the chromatographic material having the sorbed component with a solvent under conditions so as to desorb the component from the porous materials; and, optionally, determining the level of the desorbed component.

In an aspect, the present disclosure pertains to a porous material that comprises a copolymer of a least one hydrophobic monomer and at least one hydrophilic monomer selected from 4-acryloymorphine, N-(3-methoxypropyl)acrylamide, N,N′-methylenebis(acrylamide), acrylonitrile, ethylene glycol dimethacrylate, methyl acrylate, 4-acetoxystyrene, 4-vinyl pyridine, or a boronic-acid-containing monomer, wherein more than 10% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 200 Å, wherein said material has a median pore diameter of about 100 Å to about 1000 Å, or both.

In an aspect, the present disclosure pertains to a porous material that comprises a copolymer of a least one hydrophobic monomer and at least one hydrophilic monomer having a log P value of less than 0.5, wherein more than 10% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 200 Å, wherein said material has a median pore diameter of about 100 Å to about 1000 Å, or both. For example, the hydrophilic monomer may be 4-acryloymorphine, N-(3-methoxypropyl)acrylamide, N,N′-methylenebis(acrylamide), or acrylonitrile, among others.

In an aspect, the present disclosure pertains to a porous material that comprises a copolymer of at least one hydrophobic monomer and at least one hydrophilic monomer, wherein at least one of the hydrophilic monomers is a boronic-acid-containing monomer.

In some embodiments, the porous materials in accordance with the above aspects are in the form of porous particles.

In some embodiments, the porous materials in accordance with the above aspects are in the form of a porous monolith.

In some embodiments, the hydrophobic monomer in the porous materials in the above aspects and embodiments may be divinylbenzene or styrene. In some embodiments, the nitrogen content of the porous materials in the above aspects and embodiments is from about 0.5% N to about 20% N.

In some embodiments, more than 10% of the BJH surface area of the porous materials in the above aspects and embodiments is contributed by pores that have a diameter greater than or equal to 200 Å and the porous materials in the above aspects and embodiments have a median pore diameter of about 100 Å to about 1000 Å.

In some embodiments, the porous materials in the above aspects and embodiments have ion-exchange functional moieties present at a concentration of about 0.01 to about 10.0 milliequivalents per gram of porous material. In some embodiments, the porous materials in the above aspects and embodiments are used for solid phase extraction or chromatography.

In some aspects, a method for removing or isolating a component from a mixture is provided, which comprises: contacting the mixture with a chromatographic material comprising a porous material in accordance with any of the above aspects and embodiments, to thereby remove or isolate the component from the mixture. In some embodiments, the mixture is an inclusion body, a biological fluid, a biological tissue, a biological matrix, an embedded tissue sample, or a cell culture supernatant. In some embodiments, the component is a biological material. For example, the biological material may be an intact protein, a denatured protein, a modified protein, an oligonucleotide, a modified oligonucleotide, a single-stranded oligonucleotide, a double-stranded oligonucleotide, DNA, RNA, or a peptide.

In some aspects, a method for determining the level of a component in a mixture is provided, which comprises: a) contacting the mixture with a chromatographic material comprising a porous material in accordance with any of the above aspects and embodiments under conditions that allow for sorption of the component onto the porous materials; b) washing the chromatographic material having the sorbed component with a solvent under conditions so as to desorb the component from the porous materials; and c) determining the level of the desorbed component. In some embodiments, the mixture is an inclusion body, a biological fluid, a biological tissue, a biological matrix, an embedded tissue sample, or a cell culture supernatant. In some embodiments, the component is a biological material. For example, the biological material may be an intact protein, a denatured protein, a modified protein, an oligonucleotide, a modified oligonucleotide, a single-stranded oligonucleotide, a double-stranded oligonucleotide, DNA, RNA, or a peptide.

In some aspects, a separation device is provided which comprises a porous material in accordance with any of the above aspects and embodiments. For example, the separation device may be selected from chromatographic columns, cartridges, thin layer chromatographic plates, filtration membranes, sample clean up devices, solid phase organic synthesis supports, and microtiter plates, among others.

In some aspects, a solid phase extraction cartridge is provided which comprises a porous material in accordance with any of the above aspects and embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts the percent nitrogen content vs. BET average pore diameter of representative porous materials of the invention and standard materials.

FIGS. 2A-2B depict the BJH Desorption dV/dlog(D) pore volume plots of representative porous materials of the invention (FIG. 2A) and standard materials (FIG. 2B). The graph presents pore diameter distributions of materials made by standard methods and those made by the methods of the invention as determined by BJH analysis

FIGS. 3A-3C shows SEM depictions of a) standard materials having a BET average pore diameter of about 91 Å(FIG. 3A); b) materials of the invention having a BET average pore diameter of about 146 Å(FIG. 3B); and c) materials of the invention having an average pore diameter of about 500 Å(FIG. 3C).

FIGS. 4A-4C shows SEM depictions of representative materials of the invention produced during scaled productions and a close-up comparison of the materials of the invention as compared to a standard material produced using toluene and N-vinylpyrrolidone. FIG. 4A shows Representative SEM of particles produced by the Process of Example 5. FIGS. 4B-4C show Close-up SEM comparison of surface morphologies between wide pore particles of the invention (FIG. 4A) and standard particles comprising non-polar porogens and N-vinyl pyrrolidone (FIG. 4B).

FIG. 5 shows an SEM depiction of a material produced by the process of Example 6 using polar porogens, DVB and N-vinylpyrrolidone which demonstrates the inability of N-vinylpyrrolidone to produce wide pore materials like the materials of the invention.

FIGS. 6A-6E show representative plots of the BJH surface area vs pore diameter of representative compounds of the invention as compared to a standard material as determined using a nitrogen gas desorption isotherm at 77.3K. FIGS. 6A-6B show graphs of the cumulative BJH surface area vs the pore diameter. FIGS. 6C-6E show graphs of the BJH surface area vs the pore diameter in which the value of the cumulative BJH surface area at the higher pore diameter is subtracted from the value at the next lowest pore diameter. For FIGS. 6C-6E, each point represents the BJH surface area contributed by the range (APD+50 Å)—APD.

FIG. 7A is a plot of BJH differential surface area (m²/g) vs pore diameter (Å) for the product of Example 8-1. FIG. 7B is a plot of BJH differential pore volume (m³/g) vs pore diameter (Å) for the product of Example 8-1.

FIG. 8A is a plot of BJH differential surface area (m²/g) vs pore diameter (Å) for the product of Example 9-1. FIG. 8B is a plot of BJH differential pore volume (m³/g) vs pore diameter (Å) for the product of Example 9-1.

DETAILED DESCRIPTION OF THE INVENTION
Definitions

The present invention will be more fully illustrated by reference to the definitions set forth below.

The term “BET surface area” describes the specific surface area of a material as determined by standard BET techniques for analysis of gas adsorption-desorption, such as those described in Gregg, S. J. and Sing, K. S. W. (1982) Adsorption, Surface Area and Porosity, p. 303 Academic Press, London; and Lowell, S. and Shields, J. E. (1991) Powder surface area and porosity (3rd edition), p. 245. Chapman and Hall, U.K. In specific aspects of the invention, the BET surface area is as measured by BET analysis of nitrogen gas adsorption at 77.3K.

The term “BJH surface area” describes the specific surface area of a material as determined by standard BJH techniques for analysis, such as those described in Barret et al. J. Am. Chem. Soc. (1951), vol. 73, pp. 373-380. In specific aspects of the invention, the BJH surface area and pore diameter are determined using a nitrogen gas adsorption desorption isotherm at 77.3K.

The term “hydrophilic” describes having an affinity for, attracting, adsorbing or absorbing water.

The term “hydrophobic” describes lacking an affinity for, repelling, or failing to adsorb or absorb water.

The term “log P” as used herein, refers to the octanol: water partition coefficient at 25° C. The formula for the partition coefficient is log P=[analyte concentration in octanol]/[analyte concentration in water]. The log P value, also sometimes referred to as log P_owor log K_ow, is used as a measure of substances hydrophobicity or hydrophobicity where higher log P values indicate that the substance is more hydrophobic, whereas lower log P values are an indication that the substance is more hydrophilic. In other words, higher log P values correlate with a higher hydrophobicity relative to lower log P values. Conversely, lower log P values correlate with a higher hydrophilicity relative to higher log P values.

The term “ion-exchange functional group” is intended to include a group where the counter-ion is partially free and can readily be exchanged for other ions of the same sign.

The term “mole percent” describes the mole fraction, expressed as a percent, of the monomer of interest relative to the total moles of the various (two or more) monomers that comprise the copolymer of the porous material of the invention.

The term “monolith” is intended to include a porous, three-dimensional material having a continuous interconnected pore structure in a single piece. A monolith is prepared, for example, by casting precursors into a mold of a desired shape. The term monolith is meant to be distinguished from a collection of individual particles packed into a bed formation, in which the end product still comprises individual particles in bed formation.

The term “monomer” is intended to include a molecule comprising one or more polymerizable functional groups prior to polymerization, or a repeating unit of a polymer.

The term “porous material” is intended to include a member of a class of porous crosslinked polymers penetrated by pores through which solutions can diffuse. Pores are regions between densely packed polymer chains.

The term “random ordering” is intended to include ordering in which individual units are joined randomly.

The term “solid phase extraction” is intended to include a process employing a solid phase for isolating classes of molecular species from fluid phases such as gases and liquids by, e.g., sorption, ion-exchange, chelation, size exclusion (molecular filtration), affinity or ion pairing mechanisms.

The term “sorption” describes the ability of a material to take up and hold another material by absorption or adsorption.

The term “surface modifiers” includes (typically) functional groups which impart a certain chromatographic functionality to the material.

The language “surface modified” is used herein to describe the composite material of the present invention that possess organic groups which may additionally be substituted or derivatized with a surface modifier. “Surface modifiers” include (typically) organic functional groups that impart a certain chromatographic functionality to the material.

The language “surface functionalized” is used herein to describe the composite material of the present invention that possess ion-exchange functional groups that impart a certain chromatographic functionality to the material.

BET and BJH Analysis

BET theory is used to explain the physical adsorption of gas molecules on a solid surface. The theory was developed by Stephen Brunauer, Paul Hugh Emmett, and Edward Teller and serves as the basis for an important analysis technique for the measurement of the specific surface area of a material.

In physical gas adsorption, an inert gas, typically nitrogen, is adsorbed on the surface of a solid material. This occurs on the outer surface and, in case of porous materials, also on the surface of pores. Adsorption of nitrogen at a temperature of 77 K leads to a so-called adsorption isotherm, sometimes referred to as BET isotherm, which is mostly measured over porous materials. In specific cases, the use of argon adsorption, carbon dioxide or krypton gas adsorption may be used instead of nitrogen adsorption to accurately probe the micropores.

Monolayer formation of gas molecules on the surface is used to determine the specific surface area, while the principle of capillary condensation can be applied to assess the presence of pores, pore volume and pore size distribution.

In general, two different techniques can be distinguished:

The flow technique uses a detector to obtain information on the amount of adsorbed gas resulting in a specific BET surface area and/or total pore volume.

The volumetric technique measures many adsorption and/or desorption points providing a full isotherm with information on BET surface area, pore volume and pore size distribution.

Standard BET analysis techniques are well known in the art and can be found, for example, in Gregg, S. J. and Sing, K. S. W. (1982) Adsorption, Surface Area and Porosity, p. 303 Academic Press, London and in Lowell, S. and Shields, J. E. (1991) Powder surface area and porosity (3rd edition), p. 245. Chapman and Hall, U.K. The disclosures of each of these references are incorporated herein by reference in their entireties.

BJH Analysis is used to estimate the volume and area of porous adsorbents available to molecules of various sizes. BJH Analysis is related to the BET and can also be employed to determine pore area and specific pore volume using adsorption and desorption techniques. This technique characterizes pore size distribution independent of external area due to particle size of the sample. BJH Analysis was developed by Elliot Barrett, Leslie Joyner and Paul Halenda.

FIG. 6 shows representative plots of the BJH surface area vs pore diameter of representative compounds of the invention as compared to a standard material as determined using a nitrogen gas desorption isotherm at 77.3K. FIGS. 6A-6B show graphs of the cumulative BJH surface area vs the pore diameter. FIGS. 6C-6E show graphs of the BJH surface area vs the pore diameter in which the value of the cumulative BJH surface area at the higher pore diameter is subtracted from the value at the next lowest pore diameter. Thus, the associated BJH surface area in FIGS. 6C-6E is not a cumulative surface area, but rather, a representation of the overall surface area associated with or contributed by a given pore diameter across the range of the subtraction. Thus, for example, the value shown at 900 in the FIGS. 6C-6E graphs is representative of the BJH surface area associated with the 900 to 950 Å pores.

The percentage of the BJH surface area contributed by pores greater than 200 Å, for example, can be calculated by dividing the cumulative BJH surface from 200 Å to 2000 Å by the cumulative BJH surface area from the lowest pore diameter recorded (e.g. 17 Å) to 2000 Å—which represents the total BET surface area of the material—and multiplying by 100.

Compositions and Methods of the Invention

In one aspect, the invention provides a porous material comprising a copolymer of a least one hydrophobic monomer and at least one hydrophilic monomer, wherein more than 10% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 200 Å. In certain aspects, more than 12.5% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 200 Å. In certain aspects, more than 15% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 200 Å. In certain aspects, more than 17.5% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 200 Å. In certain aspects, more than 25% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 200 Å. In certain aspects, more than 50% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 200 Å. In certain aspects, more than 75% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 200 Å. In certain aspects, more than 90% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 200 Å. In certain aspects, more than 95% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 200 Å.

In another aspect, the invention provides a porous material comprising a copolymer of a least one hydrophobic monomer and at least one hydrophilic monomer, wherein more than 10% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 300 Å. In certain aspects, more than 12.5% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 300 Å. In certain aspects, more than 15% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 300 Å. In certain aspects, more than 25% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 300 Å. In certain aspects, more than 50% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 300 Å. In certain aspects, more than 75% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 300 Å. In certain aspects, more than 90% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 300 Å. In certain aspects, more than 95% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 300 Å.

In another aspect, the invention provides a porous material comprising a copolymer of a least one hydrophobic monomer and at least one hydrophilic monomer, wherein more than 10% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 500 Å. In certain aspects, more than 12.5% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 500 Å. In certain aspects, more than 15% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 500 Å. In certain aspects, more than 25% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 500 Å. In certain aspects, more than 50% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 500 Å. In certain aspects, more than 75% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 500 Å. In certain aspects, more than 90% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 500 Å. In certain aspects, more than 95% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 500 Å.

In still another aspect, the invention provides a porous material comprising a copolymer of a least one hydrophobic monomer and at least one hydrophilic monomer, wherein more than 12.5% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 200 Å and more than 10% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 300 Å. In certain embodiments, more than 15% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 200 Å and more than 10% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 300 Å. In other embodiments, more than 17.5% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 200 Å and more than 10% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 300 Å.

In still another aspect, the invention provides a porous material comprising a copolymer of a least one hydrophobic monomer and at least one hydrophilic monomer, wherein more than 12.5% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 300 Å and more than 10% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 400 Å. In certain embodiments, more than 15% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 300 Å and more than 10% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 400 Å. In other embodiments, more than 17.5% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 300 Å and more than 10% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 400 Å.

In yet another aspect, the invention provides a porous material comprising a copolymer of a least one hydrophobic monomer and at least one hydrophilic monomer, wherein, more than 15% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 200 Å and more than 12.5% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 300 Å. In other embodiments, more than 17.5% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 200 Å and more than 12.5% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 300 Å.

In yet another aspect, the invention provides a porous material comprising a copolymer of a least one hydrophobic monomer and at least one hydrophilic monomer, wherein, more than 15% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 300 Å and more than 12.5% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 400 Å. In other embodiments, more than 17.5% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 300 Å and more than 12.5% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 400 Å.

In still yet another aspect, the invention provides a porous material comprising a copolymer of a least one hydrophobic monomer and at least one hydrophilic monomer, wherein more than 17.5% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 200 Å and more than 15% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 300 Å.

In still yet another aspect, the invention provides a porous material comprising a copolymer of a least one hydrophobic monomer and at least one hydrophilic monomer, wherein more than 17.5% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 300 Å and more than 15% of the BJH surface area of the porous material is contributed by pores that have a diameter greater than or equal to 400 Å.

In still yet another aspect, the invention provides a porous material comprising a copolymer of a least one hydrophobic monomer and at least one hydrophilic monomer, wherein more than 25% of the BJH surface area of the porous material is contributed by pores that have a diameter that is greater than or equal to 200 Å and less than or equal to 300 Å.

In still yet another aspect, the invention provides a porous material comprising a copolymer of a least one hydrophobic monomer and at least one hydrophilic monomer, wherein more than 50% of the BJH surface area of the porous material is contributed by pores that have a diameter that is greater than or equal to 200 Å and less than or equal to 300 Å.

In still yet another aspect, the invention provides a porous material comprising a copolymer of a least one hydrophobic monomer and at least one hydrophilic monomer, wherein more than 75% of the BJH surface area of the porous material is contributed by pores that have a diameter that is greater than or equal to 200 Å and less than or equal to 300 Å.

In still yet another aspect, the invention provides a porous material comprising a copolymer of a least one hydrophobic monomer and at least one hydrophilic monomer, wherein more than 25% of the BJH surface area of the porous material is contributed by pores that have a diameter that is greater than or equal to 250 Å and less than or equal to 350 Å.

In still yet another aspect, the invention provides a porous material comprising a copolymer of a least one hydrophobic monomer and at least one hydrophilic monomer, wherein more than 50% of the BJH surface area of the porous material is contributed by pores that have a diameter that is greater than or equal to 250 Å and less than or equal to 350 Å.

In still yet another aspect, the invention provides a porous material comprising a copolymer of a least one hydrophobic monomer and at least one hydrophilic monomer, wherein more than 75% of the BJH surface area of the porous material is contributed by pores that have a diameter that is greater than or equal to 250 Å and less than or equal to 350 Å.

In still yet another aspect, the invention provides a porous material comprising a copolymer of a least one hydrophobic monomer and at least one hydrophilic monomer, wherein more than 25% of the BJH surface area of the porous material is contributed by pores that have a diameter that is greater than or equal to 300 Å and less than or equal to 400 Å.

In still yet another aspect, the invention provides a porous material comprising a copolymer of a least one hydrophobic monomer and at least one hydrophilic monomer, wherein more than 50% of the BJH surface area of the porous material is contributed by pores that have a diameter that is greater than or equal to 300 Å and less than or equal to 400 Å.

In still yet another aspect, the invention provides a porous material comprising a copolymer of a least one hydrophobic monomer and at least one hydrophilic monomer, wherein more than 75% of the BJH surface area of the porous material is contributed by pores that have a diameter that is greater than or equal to 300 Å and less than or equal to 400 Å.

In still yet another aspect, the invention provides a porous material comprising a copolymer of a least one hydrophobic monomer and at least one hydrophilic monomer, wherein more than 25% of the BJH surface area of the porous material is contributed by pores that have a diameter that is greater than or equal to 350 Å and less than or equal to 450 Å.

In still yet another aspect, the invention provides a porous material comprising a copolymer of a least one hydrophobic monomer and at least one hydrophilic monomer, wherein more than 50% of the BJH surface area of the porous material is contributed by pores that have a diameter that is greater than or equal to 350 Å and less than or equal to 450 Å.

In still yet another aspect, the invention provides a porous material comprising a copolymer of a least one hydrophobic monomer and at least one hydrophilic monomer, wherein more than 75% of the BJH surface area of the porous material is contributed by pores that have a diameter that is greater than or equal to 350 Å and less than or equal to 450 Å.

In still yet another aspect, the invention provides a porous material comprising a copolymer of a least one hydrophobic monomer and at least one hydrophilic monomer, wherein more than 25% of the BJH surface area of the porous material is contributed by pores that have a diameter that is greater than or equal to 400 Å and less than or equal to 500 Å.

In still yet another aspect, the invention provides a porous material comprising a copolymer of a least one hydrophobic monomer and at least one hydrophilic monomer, wherein more than 50% of the BJH surface area of the porous material is contributed by pores that have a diameter that is greater than or equal to 400 Å and less than or equal to 500 Å.

In still yet another aspect, the invention provides a porous material comprising a copolymer of a least one hydrophobic monomer and at least one hydrophilic monomer, wherein more than 75% of the BJH surface area of the porous material is contributed by pores that have a diameter that is greater than or equal to 400 Å and less than or equal to 500 Å.

In yet another aspect, the BJH surface area of the porous materials of the invention as described herein is measured by BJH analysis of nitrogen gas adsorption at 77.3K.

In another aspect, the invention provides a porous material comprising a copolymer of a least one hydrophobic monomer and at least one hydrophilic monomer, wherein said material has a median pore diameter of about 100 Å to about 2500 Å or more. Median pore diameter can be measured, for example, by inverse size exclusion chromatography (I-SEC). In certain aspects, the material has a median pore diameter ranging from about 100 Å to about 200 Å to about 300 Å to about 400 Å to about 500 Å to about 600 Å to about 700 Å to about 800 Å to about 900 Å to about 1000 Å to about 1250 Å to about 1500 Å to about 1750 Å to about 2000 Å to about 2500 Å (i.e., having a median pore diameter ranging between any two of these values), for example, of about 200 Å to about 800 Å; about 300 Å to about 550 Å; about 100 Å; about 200 Å; about 300 Å; about 400 Å; about 425; about 450 Å; about 475 Å; about 500 Å; about 525 Å; about 550 Å; about 575 Å; about 600 Å; about 700 Å; or about 800 Å.

The invention further provides a porous material comprising a copolymer of a least one hydrophobic monomer and at least one hydrophilic monomer, wherein said material has nitrogen content from about 0.5% N to about 20% N. In certain aspects the porous material has a nitrogen content ranging from about 0.5% N to about 1.0% N to about 1.5% N to about 2.0% N to about 2.5% N to about 3.0% N to about 4.0% N to about 5.0% N to about 7.5% N to about 10% N to about 12.5% N to about 15% N to about 20% N, for example, from about 1% N to about 10% N; from about 1% N to about 5% N; from about 1% N to about 4% N; about 1% N; about 1.5% N; about 2% N; about 2.5% N; about 3% N; about 3.5% N; about 4% N; about 4.5% N; about 5% N; about 5.5% N; about 6% N; about 6.5% N; about 7% N; about 7.5% N; about 8% N; about 8.5% N; about 9% N; about 9.5% N; about 10% N; about 10.5% N; about 11% N; about 11.5% N; about 12% N; about 12.5% N; about 13% N; about 13.5% N; about 14% N; about 14.5% N; or about 15% N

In certain embodiments, the porous material of the invention has both a median pore diameter of a median pore diameter of ranging from about 100 Å to about 2500 Å or more, as set forth above, and a nitrogen content ranging from about 0.5% N to about 20% N, as set forth above. For example, the porous material of the invention may have a median pore diameter of about 100 Å to about 1000 Å; about 200 Å to about 900 Å; about 300 Å to about 800 Å; or about 300 Å to about 550 Å; and a nitrogen content from about 0.5% N to about 20% N; from about 1% N to about 10% N; from about 1% N to about 5% N; from about 1% N to about 4% N; about 1% N; about 1.5% N; about 2% N; about 2.5% N; about 3% N; about 3.5% N; about 4% N; about 4.5% N; about 5% N; about 5.5% N; about 6% N; about 6.5% N; about 7% N; about 7.5% N; about 8% N; about 8.5% N; about 9% N; about 9.5% N; about 10% N; about 10.5% N; about 11% N; about 11.5% N; about 12% N; about 12.5% N; about 13% N; about 13.5% N; about 14% N; about 14.5% N; or about 15% N.

In some embodiments, the porous material comprising a copolymer of a least one hydrophobic monomer and at least one hydrophilic monomer, wherein said material has an oxygen content from about 1% O to about 20% O; from about 1% O to about 10% O; from about 1% O to about 5% O; from about 1% O to about 4% O; about 1% O; about 2% O; about 3% O; about 4% O; about 5% O; about 6% O; about 7% O; about 8% O; about 9% O; about 10% O; about 11% O; about 12% O; about 13% O; about 14% O; or about 15% O.

In some embodiments, the porous material comprising a copolymer of a least one hydrophobic monomer and at least one hydrophilic monomer, wherein said material has a sulfur content from about 1% S to about 20% S; from about 1% S to about 10% S; from about 1% S to about 5% S; from about 1% S to about 4% S; about 1% S; about 2% S; about 3% S; about 4% S; about 5% S; about 6% S; about 7% S; about 8% S; about 9% S; about 10% S; about 11% S; about 12% S; about 13% S; about 14% S; or about 15% S.

In some embodiments, the porous material comprising a copolymer of a least one hydrophobic monomer and at least one hydrophilic monomer, wherein said material has a phosphorous content from about 1% P to about 20% P; from about 1% P to about 10% P; from about 1% P to about 5% P; from about 1% P to about 4% P; about 1% P; about 2% P; about 3% P; about 4% P; about 5% P; about 6% P; about 7% P; about 8% P; about 9% P; about 10% P; about 11% P; about 12% P; about 13% P; about 14% P; or about 15% P.

In certain aspects, the porous material has a specific surface area in the range from about 50 to about 1200 square meters per gram and pores having a median pore diameter ranging from about 50 Å to 1000 Å, beneficially, ranging from about 100 Å to about 2500 Å or more, as set forth above.

In certain embodiments, the porous materials of the invention take the form of porous particles, e.g., beads, pellets, or any other form desirable for use. The porous particles can have, e.g., a spherical shape, a regular shape or an irregular shape. In some embodiments, the particles are beads having a diameter in the range from about 3 or less to about 500 μm or more. In certain embodiments, the particles are beads having a diameter ranging from about 3 μm to about 3 μm to about 5 μm to about 10 μm to about 15 μm to about 20 μm to about 30 μm to about 50 μm to about 75 μm to about 100 μm to about 200 μm to about 300 μm to about 400 μm to about 500 μm, for example, from about 10 to about 300 μm, or from about 20 to about 200 μm. In other embodiments, the particles are beads having a diameter in the range from about 3 to about 30 μm, from about 5 to about 20 μm, or from about 10 to about 15 μm.

In other embodiments, the porous materials of the invention take the form of porous monoliths. In certain embodiments, the monoliths have the following characteristics: surface area ranging from about 50 to about 1200 m²/g, more particularly about 300 to about 700 m²/g; pore volume ranging from about 0.2 to about 2.5 cm³/g, more particularly about 0.4 to about 2.0 cm³/g, still more particularly about 0.6 to about 1.4 cm³/g; and median pore diameter ranging from about 20 to about 500 Å, more particularly about 50 to 300 Å, still more particularly about 80 to about 150 Å.

Component Materials of the Invention

The porous materials of the invention comprise a copolymer comprising a least one hydrophobic monomer and at least one hydrophilic monomer. In certain embodiments, the copolymer of the invention is non-sulfonated. In certain other embodiments, the copolymer is sulfonated.

Hydrophobic Monomers

In certain embodiments the hydrophobic monomer comprises an aromatic carbocyclic group, e.g., a phenyl group or a phenylene group, or a straight chain C₂-C₁₈-alkyl group or a branched chain C₂-C₁₈-alkyl group.

In certain embodiments the hydrophobic monomer comprises a C₆-C₁₈monocyclic or multicyclic carbocyclic group, e.g., a phenyl group or a phenylene group.

In certain embodiments the hydrophobic monomer is a monomer having a log P value of 1.5 or more. In certain embodiments the hydrophobic monomer is a monomer having a log P value of 2.0 or more. In certain embodiments the hydrophobic monomer is a monomer having a log P value of 2.5 or more. Specific examples of hydrophobic monomers include, for example, monofunctional and multifunctional aromatic monomers such as styrene and divinylbenzene, monofunctional and multifunctional olefin monomers such as ethylene, propylene or butylene, polycarbonate monomers, ethylene terephthalate, monofunctional and multifunctional fluorinated monomers such as fluoroethylene, 1,1-difluoroethylene, tetrafluoroethylene, chlorotrifluoroethylene, hexafluoropropylene, perfluoropropylvinylether, or perfluoromethylvinylether, monofunctional or multifunctional acrylate monomers having a higher (C₈-C₁₈) alkyl group, higher alkylene group or higher alkynylene group. monofunctional or multifunctional acrylate monomers having a C₈-C₁₈saturated, unsaturated or aromatic carbocyclic group, monofunctional or multifunctional methacrylate monomers having a higher alkyl group, higher alkylene group or higher alkynylene group, monofunctional or multifunctional methacrylate monomers having a C₈-C₁₈saturated, unsaturated or aromatic carbocyclic group, among others.

The hydrophobic monomer can be, e.g., styrene or divinylbenzene. In certain embodiments, DVB 80 may be employed, which is a monomer mixture that comprises divinylbenzene (80%) as well as a mixture of ethyl-styrene isomers, diethylbenzene, and can include other isomers as well.

A preferred copolymer is a poly(divinylbenzene-co-N-vinylcaprolactam).

In some embodiments, the hydrophobic monomer is further substituted by at least one haloalkyl group.

Hydrophilic Monomers

In certain embodiments, the hydrophilic organic monomer may be selected from organic monomers having one or more of the following groups: an amide group, an ester group, a carbonate group, a carbamate group, a urea group, a hydroxyl group, or a nitrogen-containing heterocyclic group

In certain embodiments the hydrophilic monomer is a monomer having the formula:

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wherein n is an integer from 1-3.

In certain embodiments the hydrophilic monomer is a monomer of the formula:

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wherein R₁and R₂are independently selected from C₁-C₆alkylene, C₂-C₆alkenylene, C₂-C₆alkynylene, or C₆-C₁₈arylene groups.

In certain embodiments the hydrophilic monomer is a monomer having a log P value of less than 1.5. In certain embodiments the hydrophilic monomer is a monomer having a log P value of less than 1.0. In certain embodiments the hydrophilic monomer is a monomer having a log P value of less than 0.5. In certain embodiments the hydrophilic monomer is a monomer having a log P value of less than 0.0.

Specific examples of hydrophilic monomers include vinyl imidazoles such as 1-vinyl-1,3-imidazole,

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N-vinylpyrrolidone, N-vinylcaprolactam, vinyl pyridines such as 2-vinyl pyridine, 3-vinyl pyridine, 4-vinyl pyridine,

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vinyl triazoles such as 1-vinyl-1,2,4-triazole,

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boronic-acid-containing monomers such as 3-(acrylamido) phenylboronic acid, 4-vinylphenylboronic acid, or but-1-ene-4-boronic acid, nitrostyrenes such as 4-nitrostyrene,

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acetoxylstyrenes such as 2-acetoxylstyrene, 3-acetoxylstyrene, 4-acetoxylstyrene,

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methacryloyloxyalkyl phosphorylcholines such as 2-methacryloyloxyethyl phosphorylcholine,

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N-[tris(hydroxyethyl)methyl]acrylamide

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acrylonitrile,

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[2-(methacryloyloxy)alkyl]dimethyl-(sulfoalkyl)ammonium hydroxides such as [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide,

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N-vinyl-piperidone,

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lower alkyl (C₁-C₆) acrylates (e.g., methyl acrylate, ethyl acrylate, propyl acrylate, etc.), lower alkyl (C₁-C₆) methacrylates (e.g., methyl methacrylate, ethyl methacrylate, propyl acrylate etc.), vinyl acetate, acrylamide, N,N′-methylenebis(acrylamide), N-(3-methoxypropyl)acrylamide, methacrylamide, 4-acryloymorphine, ethoxy ethyl methacrylate, ethylene glycol dimethacrylate, or diallyl maleate, among others.

In certain embodiments, the hydrophilic monomer is N-vinyl caprolactam, N-vinyl pyrrolidone N-vinyl acetamide, acrylonitrile, 4-vinyl pyridine or a boronic-acid-containing monomer. In specific embodiments, the hydrophilic monomer is not N-vinylpyrrolidone.

In some embodiments, the hydrophilic monomer is further substituted by at least one haloalkyl group.

In certain embodiments the hydrophilic monomer comprises one or more sulfur, phosphorous, nitrogen and/or oxygen atoms.

In one embodiment, the hydrophobic monomer is divinylbenzene or styrene, and the hydrophilic monomer is N-vinyl caprolactam, N-vinyl acetamide, n-vinyl pyrrolidone, acrylonitrile, 4-vinyl pyridine, or a boronic-acid-containing monomer.

In a specific embodiment, the copolymer is a poly(divinylbenzene-co-N-vinylcaprolactam). In certain embodiments, the porous material comprises at least about 8 mole percent N-vinylcaprolactam. In still other embodiments, the porous material comprises at least about 15 mole percent N-vinylcaprolactam. In yet other embodiments, the porous material comprises from about 5 to about 35 mole percent N-vinylcaprolactam; from about 7 to about 33 mole percent N-vinylcaprolactam; from about 9 to about 32 mole percent N-vinylcaprolactam; from about 10 to about 30 mole percent N-vinylcaprolactam; from about 15 to about 30 mole percent N-vinylcaprolactam; from about 17.3 to about 29.6 mole percent N-vinylcaprolactam.

The porous materials, in either porous particle or monolith form, are advantageously used for solid phase extraction or chromatography. In a one embodiment, the porous material comprises at least one porous particle, and more preferably a plurality of porous particles. In one embodiment, the porous material comprises the copolymer poly(divinylbenzene-co-N-vinylcaprolactam). In a related embodiment, the poly(divinylbenzene-co-N-vinylcaprolactam) has ion-exchange functional moieties present at a concentration of about 0.01 to about 10.0 milliequivalents per gram of porous material (see below).

Surface Functionalization/Modification

The porous materials, in either porous particle or monolith form, may be functionalized to provide an ion-exchange functional moiety.

In certain embodiments, porous material has ion-exchange functional moieties present at a concentration of about 0.01 to about 0.03 to about 0.05 to about 0.10 to about 0.3 to about 0.5 to about 1.0 to about 3.0 to about 5.0 to about 10.0 milliequivalents per gram of porous material. For example, the porous material may have ion-exchange functional moieties present at a concentration of about 0.01 to about 5.0 milliequivalents per gram of porous material; about 0.01 to about 3.0 milliequivalents per gram of porous material; or about 0.01 to about 1.0 milliequivalents per gram of porous material.

In certain embodiments, the ion-exchange functional moiety can be formed by formation of an amine functionality on materials of the invention, for example, after cholomethylation as in the methods described in U.S. Pat. No. 7,731,844, which is incorporated herein by reference. In other embodiments, an amine functionality can be formed by direct reaction with a neat amine.

In accordance with the invention, the ion-exchange functional moiety can be formed from a substituted acyclic amine or a substituted cyclic amine. The substitution can be at any of the ring atoms, including heteroatoms. For example, in certain embodiments, the ion-exchange functional moiety is a substituted cyclic secondary amine, e.g., N-methyldiazinane and 4-methylpiperidine.

In other embodiments, the aforesaid amines are advantageously substituted by an electron withdrawing group. In certain embodiments, the electron withdrawing group is selected from the group consisting of halogens, aromatic groups, unsaturated groups, ethers, thioethers, nitriles, nitro groups, esters, amides, carbamates, ureas, carbonates, sulfonamides, sulfones, sulfoxides and heteroatoms, e.g., N, O and S. In certain embodiments, the electron withdrawing group is a halogen, an ether, or an aromatic group.

In accordance with the invention, the electron withdrawing group of the amine has the effect of lowering the average pK_aof the conjugate acid of the amine as compared to the conjugate acid of the amine without the electron withdrawing group. In certain embodiments, the pK_aranges from about 5 to about 7.

In certain embodiments, the ion-exchange functional moiety can be formed from an acyclic amine substituted with an electron withdrawing group or a cyclic secondary amine substituted with an electron withdrawing group.

In certain embodiments, the acyclic amine substituted with an electron withdrawing group includes benzylamine, N-methylbenzylamine, N-ethylbenzylamine, N-propylbenzylamine, N-butylbenzylamine, N-pentylbenzylamine, N-hexylbenzylamine, N-heptylbenzylamine, N-octylbenzylamine, N-nonylbenzylamine, N-decylbenzylamine, N-undecylbenzylamine, N-dodecylbenzylamine, N-tridecylbenzylamine, N-tetradecylbenzylamine, N-pentadecylbenzylamine, N-hexadecylbenzylamine, N-heptadecylbenzylamine, N-octadecylbenzylamine, dibenzylamine, aniline, N-methylaniline, N-ethylaniline, N-propylaniline, N-butylaniline, N-pentylaniline, N-hexylaniline, N-heptylaniline, N-octylaniline, N-nonylaniline, N-decylaniline, N-undecylaniline, N-dodecylaniline, N-tridecylaniline, N-tetradecylaniline, N-pentadecylaniline, N-hexadecylaniline, N-heptadecylaniline, N-octadecylaniline, bis(2,2,2-trifluoromethyl)amine, phenethylamine, N-methylphenethylamine, 4-methylphenethylamine, 3-phenylpropylamine, 1-methyl-3-phenylpropylamine, N-isopropylbenzylamine, and 4-phenylbutylamine. In certain preferred embodiments, the acyclic amine substituted with an electron withdrawing group is benzylamine, N-methylbenzylamine, or phenethylamine. In a preferred embodiment, the acyclic amine substituted with an electron withdrawing group is N-methylbenzylamine.

In certain embodiments, the cyclic secondary amines substituted with an electron withdrawing group include oxazetane, oxazolane, oxazinane, oxazepane, oxazocane, oxazonane, oxazecane, thiazetane, thiazolane, thiazinane, thiazepane, thiazocane, thiazonane, and thiazecane. In one embodiment, the cyclic secondary amine is 1,4-oxazinane. In these embodiments, one of ordinary skill in the art will appreciate that the electron withdrawing group is a second heteroatom that has substituted for a carbon atom in the ring. For example, the ring carbon adjacent to the nitrogen atom in azetidine is substituted by an oxygen to yield oxazetane, an amine encompassed by the term “cyclic secondary amine substituted with an electron withdrawing group”.

In certain embodiments, an ion-exchange functional moiety can be formed by reaction of the materials of the invention with hydrogen peroxide.

In certain embodiments, surface functionalization can be attained on the materials of the invention by the methods described in U.S. Pat. Nos. 7,232,520 and 7,731,844, which are incorporated herein by reference.

In certain embodiments, the materials of the invention may be surface modified by coating with a polymer.

In certain embodiments, the materials of the invention may be surface modified by a combination of organic group modification and coating with a polymer. In a further embodiment, the organic group comprises a chiral moiety.

In certain embodiments, the materials of the invention may be surface modified via formation of an organic covalent bond between an organic group on the material and the modifying reagent.

Grafted Materials

In certain embodiments, the porous materials of the invention comprise a porous, a superficially porous or a non-porous core, including, but not limited to an inorganic core, an organic core or a hybrid core onto which a copolymer comprising a least one hydrophobic monomer and at least one hydrophilic monomer is grafted. In certain embodiments, the porous materials of the invention comprise a polymeric, porous core made from at least one hydrophobic monomer onto which a polymer made from a least one hydrophilic monomer is grafted. In certain embodiments, the porous materials of the invention comprise a polymeric, porous core made from at least one hydrophilic monomer onto which a polymer made from a least one hydrophobic monomer is grafted.

In such embodiments, the hydrophilic and hydrophobic monomers may be as described herein. The cores may include a silica material; a hybrid inorganic/organic material; a superficially porous material; or a superficially porous particle.

Methods of Preparation

The porous materials of the invention can be prepared via a number of processes and mechanisms including, but not limited to, chain addition and step condensation processes, radical, anionic, cationic, ring-opening, group transfer, metathesis, and photochemical mechanisms.

The copolymer can be prepared via standard synthetic methods known to those skilled in the art, e.g., as described in the examples.

Furthermore, porous material may be produced by known methods, such as those methods described in, for example, in U.S. Pat. Nos. 4,017,528; 6,528,167; 6,686,035; 7,175,913; 7,731,844 and WO2004/041398.

In addition, porous particles can be prepared in some embodiments by a suspension polymerization process in which a biphasic suspension is formed, wherein a discontinuous monomer-containing organic phase is dispersed within a continuous aqueous phase, after which the monomers in the organic phase are polymerized.

In an exemplary process, an organic phase that contains one or more hydrophobic monomers, one or more hydrophilic monomers, one or more porogens, and one or more polymerization initiators is combined with an aqueous phase that contains water and one or more emulsion stabilizers. The aqueous phase may also optionally contain one or more solubility suppressants. The resulting biphasic mixture is stirred using sufficient agitation to form oil droplets of the desired micron size. Where the initiator is a thermal initiator, the resulting suspension may then be heated to an elevated temperature under agitation to activate the thermal initiator(s) and maintained at elevated temperature until polymerization is complete. The resulting particle suspension is then cooled, filtered, washed, and dried. Where the initiator is a photoinitiator, the resulting suspension may then be illuminated under agitation with light having a suitable wavelength to activate the photoinitiator(s) and maintained until polymerization is complete. The resulting particle suspension is then filtered, washed, and dried.

Suitable hydrophobic and hydrophilic monomers for use in the organic phase are described elsewhere herein.

Any radical initiator that is compatible with the organic phase may be used, either alone or in a mixture of such radical initiators. In particular embodiments, the radical initiators are capable of being heat activated or photoactivated. In specific embodiments, the radical initiator is a peroxide, a peroxyacetate, a persulfate, an azo initiator or a mixture thereof.

As used herein, the term “porogen” is defined as a material that is capable of forming pores. Any suitable porogen may be used, either alone or in a mixture of such porogens. Porogens include organic compounds that are compatible with the organic phase, are not substantially soluble in the aqueous phase, permit the formation of a stable suspension, and do not participate in the polymerization reaction. Porogens that are good solvents for the polymer that is formed generally form smaller pores, whereas porogens that are poor solvents for the polymer that is formed generally form larger pores.

The amount of porogen(s) used will typically be dictated by the pore size and relative pore volume that is desired for the particles. For example, increasing the porogen concentration may increase the size and number of interconnecting pores, while decreasing the porogen concentration may decrease the size and number of pores.

Examples of suitable porogens that include polar and non-polar organic solvents. In addition to serving as porogens, polar organic solvents can act to retain the hydrophilic monomer in the organic phase as well. Specific examples of such organic solvents may be selected from one or more of the following: alkane and cycloalkane porogens such as hexane, heptane, isooctane, and cyclohexane; aromatic porogens such as benzene, toluene, xylene, and diethyl benzene; C₆-C₂₀alkyl alcohols, C₆-C₂₀cyclic alcohols, and C₆-C₂₀aromatic alcohols, such as hexanol, 2-ethylhexanol, octanol, decanol, dodecanol, tetradecanol, hexadecanol, octadecanol, cyclohexanol, cyclooctanol, phenol, methyl phenol, benzyl alcohol, and naphthol, among others; alkyl (e.g., C₁-C₈) esters of long chain aliphatic (e.g., C₆-C₂₀) carboxylic acids, for example, methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl and octyl esters of caproic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid or arachidic acid, alkyl (e.g., C₁-C₈) esters of aromatic acids (e.g. C₆-C₁₂aromatic acids), for example, methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl and octyl esters of benzoic acid (e.g., ethyl benzoate, butyl benzoate and octyl benzoate, etc.), phenylacetic acid (e.g., ethyl phenylacetate, butyl phenylacetate, hexyl phenylacetate and octyl phenylacetate), naphthoic acid (e.g., ethyl naphthoate, butyl naphthoate, hexyl naphthoate, octyl naphthoate, etc.), and phthalic acid (e.g., diethyl phthalate, dibutyl phthalate, dihexyl phthalate, dioctyl phthalate, etc.), among others.

Further porogens, which can be added to the organic phase and which can act to retain the hydrophilic monomer in the organic phase, include non-ionic surfactants. Examples of such non-ionic surfactants include nonionic surfactants that have a hydrophilic polyethylene oxide chain and a lipophilic hydrocarbon group such as an aromatic and/or aliphatic hydrocarbon group (e.g., as Triton® X-100), fatty acid sorbitan esters such as Span® surfactants, and polysorbate-type nonionic surfactants formed by the ethoxylation of sorbitan before the addition of a fatty acid (e.g., lauric acid) such as Tween® surfactants, nonionic surfactants containing hydrophilic polyethylene-oxide chains and n-alkyl hydrophobic chains such as Brij® surfactants, nonionic surfactants containing hydrophilic poly-ethylene-oxide chains and n-alkyl phenol hydrophobic chains such as Igepal® surfactants, and block copolymers. In some embodiments, by including such surfactants in the organic phase in sufficient concentrations, the surfactants can form reverse micelles at the surface of the dispersed organic phase droplets, which contain absorbed water from continuous phase. After polymerization, large pores may be formed by the absorbed water.

Emulsion stabilizers that can be added to the aqueous phase include, for example, polyvinyl alcohol (PVA) such as Selvol™ Polyvinyl Alcohol solution, polyvinylpyrrolidone (PVP), modified celluloses, including alkyl-modified celluloses such as methyl celluloses (e.g., Methocel™) and hydrophobically modified celluloses hydroxyethylcellulose stabilizers such as Natrosol™ cetyl modified hydroxyethylcellulose, and ionic surfactants including sodium alkyl sulfates such as sodium dodecyl sulfate (SDS) and sodium oleyl sulfate, among others.

Solubility suppressants include inorganic salts, for example, chloride, fluoride, bromide, nitrate, nitrite, sulfate, phosphate, etc. salts of Group I and Group metals (e.g., Li, Na, K, Ca, etc.), with particular examples including sodium chloride, potassium chloride or sodium sulfate, among others; water soluble organic compounds such as sugars and sugar alcohols, including glucose, sucrose, trehalose, mannitol and sorbitol; and ionic liquids.

In other embodiments, monoliths can be formed. In an exemplary process, an organic solution that contains a mixture of one or more hydrophobic monomers, one or more hydrophilic monomers, one or more porogens, and one or more polymerization initiators is poured into a mold having a desired shape and polymerized. Where the initiator is a thermal initiator, the mixture may then be heated to an elevated temperature to activate the thermal initiator(s) and maintained at elevated temperature until polymerization is complete. Where the initiator is a photoinitiator, the mixture may be illuminated with light having a suitable wavelength to activate the photoinitiator(s) and maintained until polymerization is complete.

Uses and Applications

The novel materials of the invention, e.g., in the form of porous particles or monoliths, can be used for solid phase extraction and chromatography. In some embodiments, porous materials for solid phase extraction or chromatography are provided that comprise at least one ion-exchange functional group, at least one hydrophilic component and at least one hydrophobic component. The ion-exchange functional groups enable the porous material to interact with anionic, cationic, acidic and/or basic solutes. The hydrophilic polar components enable the porous material to have polar interactions and hydrogen bonding capabilities with solutes. The hydrophobic components enable the porous material to have affinity towards nonpolar solutes through hydrophobic interaction. Since the porous materials of this invention have a combination of various interaction forces towards solutes, they are very useful materials for, e.g., solid phase extraction, ion-exchange, and liquid chromatography applications. For example, these novel porous materials can be used to bind, recover and/or remove solutes from fluids. Similarly, these novel porous materials have certain chemical affinities or attractions between the materials and certain molecules, particularly biological or biochemical molecules, such as proteins, peptides, hormones, oligonucleotides, polynucleotides, vitamins, cofactors, metabolites, lipids and carbohydrates. As such, the materials of the invention may be used to selectively adsorb and isolate certain biomolecules for analysis and or quantification.

The invention also provides a method for removing or isolating a component, e.g., a solute, from a mixture. A solution having a solute is contacted with a porous material of the invention under conditions that allow for sorption of the solute to the porous material.

The solute can be, e.g., any molecule having a hydrophobic, hydrophilic, or ionic interaction or a combination of two or three of these interactions. Preferably, the solute is an organic compound of polarity suitable for adsorption onto the porous material. Such solutes include, e.g., drugs, pesticides, herbicides, toxins and environmental pollutants, e.g., resulting from the combustion of fossil fuels or other industrial activity, such as metal-organic compounds comprising a heavy metal such mercury, lead or cadmium. The solutes can also be metabolites or degradation products of the foregoing materials. Solutes also include, e.g., biomolecules, such as proteins, peptides, hormones, oligonucleotides, polynucleotides, vitamins, cofactors, metabolites, lipids and carbohydrates. Solutes also include, e.g., modified proteins, modified oligonucleotides, single-stranded oligonucleotides, double-stranded oligonucleotides, DNA, and RNA.

The solution e.g., can comprise water, an aqueous solution, or a mixture of water or an aqueous solution and a water-miscible polar organic solvent, e.g., methanol, ethanol, N,N-dimethylformamide, dimethylsulfoxide or acetonitrile. In a preferred embodiment, the solution is an acidic, basic or neutral aqueous, i.e., between about 0% and about 99% water by volume, solution. Specific examples are provided in the experimentals. The solution comprising the solute can, optionally, further contain one or more additional solutes. In one embodiment, the solution is an aqueous solution which includes a complex variety of solutes. Solutions of this type include, e.g., blood, plasma, urine, cerebrospinal fluid, synovial fluid and other biological fluids, including, e.g., extracts of tissues, such as liver tissue, muscle tissue, brain tissue or heart tissue. Such extracts can be, e.g., aqueous extracts or organic extracts which have been dried and subsequently reconstituted in water or in a water/organic mixture. Solutions also include, e.g., ground water, surface water, drinking water or an aqueous or organic extract of an environmental sample, such as a soil sample. Other examples of solutions include a food substance, such as a fruit or vegetable juice or milk or an aqueous or aqueous/organic extract of a food substance, such as fruit, vegetable, cereal or meat. Other solutions include, e.g., natural products extractions from plants and broths.

The solution can be contacted with the porous material in any fashion which allows sorption of the solute to the porous material, such as a batch or chromatographic process. For example, the solution can be forced through a porous polymer column, disk or plug, or the solution can be stirred with the porous material, such as in a batch-stirred reactor. The solution can also be added to a porous material-containing well of a microtiter plate. The porous material can take the form of a monolith or particle, e.g., beads or pellets. The solution is contacted with the porous material for a time period sufficient for the solute of interest to substantially sorb onto the porous material. This period is typically the time necessary for the solute to equilibrate between the porous material surface and the solution. The sorption or partition of the solute onto the porous material can be partial or complete.

The invention also includes a method for analytically determining the level of solute in a solution. A solution having a solute is contacted with a porous material under conditions so as to allow sorption of the solute to the porous material. The material may comprise at least one ion-exchange functional group, at least one hydrophilic polar component and at least one hydrophobic component. The porous material having the sorbed solute is washed with a solvent under conditions so as to desorb the solute from the porous material. The level of the desorbed solute present in the solvent after the washing is analytically determined.

The solution contacted with the porous material can comprise the solute of interest in dilute form, e.g., at a concentration too low for accurate quantitation. By sorbing the solute onto the porous material and then, e.g., desorbing the solute with a substantially smaller volume of a less polar solvent, a solution which includes the solute of interest can be prepared having a substantially higher concentration of the solute of interest than that of the original solution. The method can also result in solvent exchange, that is, the solute is removed from a first solvent and re-dissolved in a second solvent.

Solvents which are suitable for desorbing the solute from the porous material can be, e.g., polar water-miscible organic solvents, such as alcohols, e.g., methanol, ethanol or isopropanol, acetonitrile, acetone, and tetrahydrofuran, or mixtures of water and these solvents. The desorbing solvent can also be, e.g., a nonpolar or moderately polar water-immiscible solvent such as dichloromethane, diethylether, chloroform, or ethylacetate. Mixtures of these solvents are also suitable. Preferred solvents or solvent mixtures must be determined for each individual case. Specific examples are provided in the experimentals. A suitable solvent can be determined by one of ordinary skill in the art without undue experimentation, as is routinely done in chromatographic methods development (see, e.g., McDonald and Bouvier, eds., Solid Phase Extraction Applications Guide and Bibliography, “A Resource for Sample Preparation Methods Development,” 6th edition, Waters, Milford, Mass. (1995); Snyder and Kirkland, Introduction to Modern Liquid Chromatography, New York: J. Wiley and Sons (1974)).

The level of the desorbed solute present in the solvent can be analytically determined by a variety of techniques known to those skilled in the art, e.g., high performance liquid chromatography, liquid chromatography/mass spectrometry, gas chromatography, gas chromatography/mass spectrometry, or immunoassay.

The invention also provides separation devices comprising the porous materials of the invention. Such devices include chromatographic columns, cartridges, thin layer chromatographic plates, filtration membranes, sample clean up devices, solid phase organic synthesis supports, and microtiter plates. In certain embodiments, more than one type of functionalized porous material can be used in the separation devices, e.g., columns, cartridges, and the like.

As noted above, the porous materials of the invention are especially well suited for solid phase extraction. Thus, the invention also includes a solid phase extraction cartridge comprising a porous material of the invention packed inside an open-ended container. In one embodiment, the porous material is packed as particles within the open-ended container to form a solid phase extraction cartridge.

The container can be, e.g., a cylindrical container or column, which is open at both ends so that the solution can enter the container through one end, contact the porous material within the container, and exit the container through the other end. In the form of porous particles, the porous material can be packed within the container as small particles, such as beads having a diameter between about 3 μm and about 500 μm; between about 5 μm and about 200 μm; or between about 10 μm and about 50 μm. In certain embodiments, the porous particles can be packed in the container enmeshed in a porous membrane.

The container can be formed of any material, which is compatible, within the time frame of the solid phase extraction process, with the solutions and solvents to be used in the procedure. Such materials include glass and various plastics, such as high density polyethylene and polypropylene. In one embodiment, the container is cylindrical through most of its length and has a narrow tip at one end. One example of such a container is a syringe barrel. The amount of porous material within the container is limited by the container volume and can range from about 0.001 g to about 50 kg, and preferably is between about 0.025 g and about 1 g. The amount of porous material suitable for a given extraction depends upon the amount of solute to be sorbed, the available surface area of the porous material and the strength of the interaction between the solute and the porous material. This amount can be readily determined by one of ordinary skill in the art. The cartridge can be a single use cartridge, which is used for the treatment of a single sample and then discarded, or it can be used to treat multiple samples.

EXAMPLES

The present invention may be further illustrated by the following non-limiting examples. All reagents were used as received unless otherwise noted. Those skilled in the art will recognize that equivalents of the following supplies and suppliers exist, and as such the suppliers listed below are not to be construed as limiting.

Materials. All materials were used as received, except as noted. N-vinylcaprolactam and NVP were obtained from ISP, Sodium oleyl sulfate was obtained from ALCOLAC. Diethylbenzene, 2-ethylhexanol, were obtained from ALDRICH. AIBN was obtained from DUPONT. Methocel E-15 and Divinylbenzene were purchased from DOW. Inhibitor was removed from DVB prior to use.

General. Those skilled in the art will recognize that equivalents of the following instruments and suppliers exist and, as such, the instruments listed below are not to be construed as limiting. The % N values were measured by combustion analysis (CE-440 Elemental Analyzer; Exeter Analytical Inc., North Chelmsford, Mass.). The specific surface areas (SSA) and the average pore diameters (APD) of these materials were measured using the multi-point N2 sorption method (Micromeritics ASAP 2400; Micromeritics Instruments Inc., Norcross, Ga., or equivalent). The specific surface area was calculated using either the BJH method or the BET method, and the average pore diameter was calculated from the desorption leg of the nitrogen isotherm at 77.3K. The BJH SSA was correlated to pore diameter using the nitrogen desorption isotherm from the BJH method.

Median Pore Diameter. The median pore sizes of these materials were determined by inverse size exclusion chromatography (I-SEC). (H. Guan and G. Guiochon, J. of Chromatogr. A, 731 (1996) 27-40). Polystyrene (PS) standards were run with tetrahydrofuran mobile phase. Toluene was used for the determination of the total pore volume (Vt) from the internal pores and external pores. The molecular size in angstrom is calculated by dividing the molecular weight of the PS standard by 41.4. (J. M. Evans, POLYMER ENGINEERING AND SCIENCE, Vol. 73 (1973) 401-408). The exclusion volume (Ve) is determined from the intersection of the two linear lines for the external and internal pores in the plot of the logarithm of molecular sizes of PS standards versus their retention volumes. The median pore diameter is defined as the molecular size corresponding to 50% internal pore volume, that is, at the retention volume equal to (Vt+Ve)/2. Median pore diameter an also be measured by other methods including mercury porosimetry (e.g., using Micromeritics AutoPore IV, Micromeritics, Norcross, Ga.) or by BET analysis of nitrogen gas adsorption at 77.3K (for pore sizes up to about 450 Å).

Particle Synthesis.

Method 1—Resin Kettle/Inline Static Mixer Syntheses (Small Scale).

These materials were synthesized in a 3 L kettle with an overhead stirrer, an inline static mixer and a peristaltic pump (FIG. 4). In all cases, the aqueous phase was prepared by dissolving 5.05 g of Methocel in 1 L of water @ 90° C. and allowing the mixture to cool to room temperature. Sodium oleyl sulfate (Sipex OS, ALCOLAC), for reactions requiring it, was added to the aqueous phase when it reached ˜50° C. The organic phase was prepared by combining the requisite amounts of DVB and either NVP or V-Cap with 1.9 g of AIBN and the requisite amounts of porogens (toluene, diethylbenzene and/or 2-ethylhexanol) in a 3 L, 4-neck kettle equipped with an overhead stirrer and a Thermowatch apparatus. With the overhead mixer turned on low, the aqueous solution was slowly added. At this point, a peristaltic pump (Cole-Parmer MasterFlex Model 7520-00), equipped with an inline static mixer was attached to the kettle via glass tubes (19/24 joints) connected to the inlet and outlet lines of the pump. The system was then purged with Ar, the overhead mixer was set to 400 RPM, and the peristaltic pump was set to 6 (˜900 mL/min.). After mixing for ˜30 minutes, the droplet size and longevity was checked using a light microscope. The target particle size was 10-30 μm in diameter, with droplets lasting for greater than 30 sec. before collapse. If these conditions were met, the peristaltic pump was allowed to empty into the kettle and then shut off. The solution was heated to 70° C., allowed to stir overnight (˜16 hours), and then cooled to room temperature. The mixture was poured into a 3 L glass filter equipped with a 20 μm cloth, the mother liquor was filtered, and the particles were washed with 3×600 mL of methanol. The resulting material was dried in a vacuum oven overnight at 80° C. and then submitted for analysis.

Example 1—Material Using N-Vinylcaprolactam Having High Percent N/Standard Average Pore Diameter

A 5 g amount of Methocel E-15 (Dow Chemical) was dissolved in 1 L of water at 90° C., then cooled to room temperature. In a separate flask, 174.5 g of divinylbenzene (DVB 80, Dow Chemical), 139.2 g of N-vinylcaprolactam (V-Cap, International Specialty Products, Wayne, N.J.), and 1.9 g of azobisisobutyronitrile (AIBN, DuPont) were dissolved and mixed in 243 g of toluene. The organic and aqueous phases were combined in a 3 L glass kettle and stirred at 400 rpm with an overhead stirrer, while running through a static mixing loop for 30 minutes. The emulsion droplet size was checked after 30 minutes. Once the desired droplet size range had been reached (by adjusting the rate of flow through the static mixer), the static mixing loop was turned off, and the mixture heated at 70° C. for 16 hours, then cooled to room temperature. The mixture was filtered using a 20 μm polyester filter cloth, washed 3× with 600 mL of methanol and dried for 16 hours under vacuum at 80° C. % N—3.34; SA—562 m²/g, BET APD—88.5 Å.

Example 2—Material Using N-Vinylcaprolactam—Standard Percent N/Standard Pore Diameter

A 5 g amount of Methocel E-15 (Dow Chemical) was dissolved in 1 L of water at 90° C., then cooled to room temperature. In a separate flask, 174.5 g of divinylbenzene (DVB 80, Dow Chemical), 87.1 g of N-vinylcaprolactam (V-Cap, International Specialty Products, Wayne, N.J.), and 1.9 g of azobisisobutyronitrile (AIBN, DuPont) were dissolved and mixed in 243 g of toluene. The organic and aqueous phases were combined in a 3 L glass kettle and stirred at 400 rpm with an overhead stirrer, while running through a static mixing loop for 30 minutes. The emulsion droplet size was checked after 30 minutes. Once the desired droplet size range had been reached (by adjusting the rate of flow through the static mixer), the static mixing loop was turned off, and the mixture heated at 70° C. for 16 hours, then cooled to room temperature. The mixture was filtered using a 20 μm polyester filter cloth, washed 3× with 600 mL of methanol and dried for 16 hours under vacuum at 80° C. % N—1.70; SA—807 m²/g, BET APD—77.0 Å.

Example 3—Material Using Polar Porogens and N-Vinylcaprolactam—Standard Percent N/High Pore Diameter

A 5 g amount of Methocel E-15 (Dow Chemical) was dissolved in 1 L of water at 90° C. After cooling to 50° C., 3.24 g of sodium oleyl sulfate (Sipex OS, ALCOLAC) was added, and then the solution was cooled to room temperature. In a separate flask, 174.5 g of divinylbenzene (DVB 80, Dow Chemical), 139.2 g of N-vinylcaprolactam (V-Cap, International Specialty Products, Wayne, N.J.), and 1.9 g of azobisisobutyronitrile (AIBN, DuPont) were dissolved in a mixture of 106 g of diethylbenzene and 128.9 g of 2-ethylhexanol. The organic and aqueous phases were combined in a 3 L glass kettle and stirred at 400 rpm with an overhead stirrer, while running through a static mixing loop for 30 minutes. The emulsion droplet size was checked after 30 minutes. Once the desired droplet size range had been reached (by adjusting the rate of flow through the static mixer), the static mixing loop was turned off, and the mixture heated at 70° C. for 16 hours, then cooled to room temperature. The mixture was filtered using a 20 μm polyester filter cloth, washed 3× with 600 mL of methanol and dried for 16 hours under vacuum at 80° C. % N—2.05; SA—552 m²/g, BET APD—145.9 Å

Example 4—Material Using Polar Porogens and Increased N-Vinylcaprolactam—High Percent N/High Pore Diameter

A 5 g amount of Methocel E-15 (Dow Chemical) was dissolved in 1 L of water at 90° C. After cooling to 50° C., 3.24 g of sodium oleyl sulfate (Sipex OS, ALCOLAC) was added, and then the solution was cooled to room temperature. In a separate flask, 174.5 g of divinylbenzene (DVB 80, Dow Chemical), 208.8 g of N-vinylcaprolactam (V-Cap, International Specialty Products, Wayne, N.J.), and 1.9 g of azobisisobutyronitrile (AIBN, DuPont) were dissolved in a mixture of 106 g of diethylbenzene and 128.9 g of 2-ethylhexanol. The organic and aqueous phases were combined in a 3 L glass kettle and stirred at 400 rpm with an overhead stirrer, while running through a static mixing loop for 30 minutes. The emulsion droplet size was checked after 30 minutes. Once the desired droplet size range had been reached (by adjusting the rate of flow through the static mixer), the static mixing loop was turned off, and the mixture heated at 70° C. for 16 hours, then cooled to room temperature. The mixture was filtered using a 20 μm polyester filter cloth, washed 3× with 600 mL of methanol and dried for 16 hours under vacuum at 80° C. % N—2.68; SA—458 m²/g, BET APD—193 Å.

The materials of the invention produced in Examples 1-4 above are summarized in the table below (Table 1)

TABLE 1

Summary of Representative Materials.

BET

Example
%
SSA

#
N
(m²/g)
APD (Å)

1
3.34
562
88.5

2
1.70
807
77.0

3
2.05
552
145.9

Repeat
2.09
576
149.1

of 3

Repeat
2.18
528
157.5

of 3

4
2.68
458
193

Example 5 a)-i) Scaled Production Using N-Vinylcaprolactam—Varied Percent N/Pore Diameter

A 55 g amount of Methocel E-15 (Dow Chemical) was dissolved in 12 L of water at 90° C. After cooling to 50° C., 35.3 g of sodium oleyl sulfate (Sipex OS, ALCOLAC) was added, and then the solution was cooled to room temperature. In a 5 L RBF, divinylbenzene (DVB 80, Dow Chemical), N-vinylcaprolactam (V-Cap, International Specialty Products, Wayne, N.J.), and 20.7 g of azobisisobutyronitrile (AIBN, DuPont) were dissolved in a mixture of diethylbenzene and 2-ethylhexanol. The organic and aqueous phases were combined in a 33 L glass reactor equipped with baffles, and stirred overhead stirrer at a rate appropriate to achieve an oil droplet size of 20 μm. The emulsion droplet size was checked after 30 minutes. The mixture was then heated at 70° C. for 16 hours, then cooled to room temperature. The mixture was filtered using a 2 μm polyester filter cloth, washed 3× with 600 mL of methanol and dried for 16 hours under vacuum at 80° C. Particles from these syntheses were highly spherical. See Table 2 for amounts and analytical data. See Table 3 for cumulative surface areas associated with various pore diameter ranges and percentages of total SA accounted for by those ranges. See FIG. 4 for representative SEM images. All materials were sized to 20 μm, with a 90/10 (v,v) ratio of 2. Results are presented in Tables 2 and 3.

TABLE 2

Reagent Amounts and Analytical Data

BET
BET
MPD

Example
DVB 80
V-Cap
DEB
2-EH
%
SSA
APD
(Å from

5
(g)
(g)
(g)
(g)
N
(m²/g)
(Å)
I-SEC)^a

a
1902
1517
1155
1405
1.84
585
166
/

b
1902
1896
1155
1405
2.24
566
177
429

c
1902
1517
863
1685
1.88
538
190
/

d
1902
1896
863
1685
2.36
509
368
521

e
1902
2655
1155
1405
3.08
432
214
308

f
1902
1517
525
2008
2.01
448
218
/

g
1902
2655
525
2008
3.12
295
245
303

h
1902
1896
525
2008
2.21
439
172
860

i
1902
2655
863
1685
2.83
421
199
450

^afor comparison, the MPD of a representative material from U.S. Pat. No. 5,882,521 was measured as 74 Å

TABLE 3

BJH Specific Surface Area Calculation

Material

Pore

Comp.

Diameter

Material

Range (Å)
5 a)
5 b)
5 c)
5 d)
5 e)
5 f)
5 g)
5 h)
5 i)
1^b

Cumulative
17-2000
376.1
356.2
324.7
149.7
261.2
238.6
169.1
237.8
253.9
537.3

Surface Area of
(Total SA)

Pores from BJH
300-
77.7
74.3
69.8
65.7
66.2
43.8
38.8
35.1
46.8
1.6

Desorption
2000

Curve
200-
100.4
94.8
87.5
81.9
83.7
54.9
49.8
46.7
61.7
34.2

(m²/g)
2000

% of Specific
300-
20.7
20.9
21.5
43.9
25.4
18.3
23.0
14.8
18.4
0.3

Surface Area^a
2000

200-
26.7
26.6
26.9
54.7
32.0
23.0
29.5
19.6
24.3
6.4

2000

^a% of Specific Surface Area calculated by:

(\frac{Cumulative SA from x - 2000 Å}{Cumulative SA from 17 - 2000 Å}) * 1 0 0

where x = 200 or 300

^bComparative Material 1 is a representative material from U.S. Pat. No. 5,882,521 having a nominal particle size of 30 μm.

Example 6—Large Scale Run Using Polar Porogens and NVP

A 55 g amount of Methocel E-15 (Dow Chemical) was dissolved in 12 L of water at 90° C. In a 5 L RBF, 1902 g of divinylbenzene (DVB 80, Dow Chemical), 1137 g of N-vinylpyrrolidone (NVP, International Specialty Products, Wayne, N.J.), and 20.7 g of azobisisobutyronitrile (AIBN, DuPont) were dissolved in a mixture of diethylbenzene and 2-ethylhexanol. The organic and aqueous phases were combined in a 33 L glass reactor equipped with baffles, and stirred overhead stirrer at a rate appropriate to achieve an oil droplet size of 20 μm. The emulsion droplet size was checked after 30 minutes. Unlike in example 5, the emulsion was unstable, and separated into the respective aqueous and organic components within 5 minutes. The mixture was then heated at 70° C. for 16 hours, then cooled to room temperature. The mixture was filtered using a 2 μm polyester filter cloth, washed 3× with 600 mL of methanol and dried for 16 hours under vacuum at 80° C. Material obtained from this synthesis has a failed morphology—it was irregular in shape and size. SEM images (FIG. 5) indicate particle collapse. % N=1.5.

Example 7—Synthesis of a Wide Pore Weak Anion Exchanger

A 20 g sample of material 5 d) was converted to a weak anion exchanger following the procedure given in U.S. Pat. No. 7,731,844 (Ion exchange capacity=0.387 meq/g).

Example 8—Material Using N-Vinylpyrrolidone (NVP) Having High Percent N/High Pore Diameter

A 5.4 grams of Celvol 540, 0.9 grams of Natrosol plus 330, 2.7 grams of SDS and 97.6 grams of Sodium chloride were charged into a 2 L round bottom flask reactor, followed by an addition of 542 grams of Milli-Q water. The solution was heated to 90° C. and then was held at 90° C. for 2 hours. At the end of 2 hours hold, the solution was cooled down to 45° C. In a separate container, 9.5 grams of N-vinyl pyrrolidone, 24.0 grams of DVB80 with inhibitor stripped off by alumina and 1.2 grams of azobisisobutyronitrile (AIBN) were dissolved and mixed in 56.9 grams of dioctyl phthalate. The organic phase was then added to the reactor and the agitation speed was adjusted to 400 rpm with an overhead stirrer. After 30 minutes mixing, the temperature was raised to 76° C. at a ramp rate of 1° C./min; Then the reaction was held at 76° C. for 20 hours then cooled to room temperature. The mixture was filtered and washed 3× with methanol, 3× with THF and finally 3× with methanol. The obtained particles were dried at 45° C. overnight under vacuum. Results are presented in Table 4. FIG. 7A is a plot of BJH differential surface area (m2/g) vs pore diameter (Å) for the product of Example 8-1. FIG. 7B is a plot of BJH differential pore volume (m3/g) vs pore diameter (Å) for the product of Example 8-1.

TABLE 4

Diethyl
Dibutyl
Dioctyl

BET
BET
BET

Example
DVB 80
NVP
phthalate
phthalate
phthalate
%
SSA
APD
Pore Mode

8
(g)
(g)
(g)
(g)
(g)
N
(m²/g)
(Å)
(Å)

1
53
21
0
125.7
0
2.25
639
139
400

2
48
19
121.4
0
0
2.96
472
211
650

3
48
19
0
0
121.4
2.31
567
199
750

Example 9—Material Using Acrylamide Derived Monomer Having High Percent N/High Pore Diameter

A 6.0 grams of Celvol 823 and 1.25 grams of sodium dodecyl sulfate (SDS) were charged into a 2 L round bottom flask reactor, followed by an addition of 500 grams of Milli-Q water. The solution was heated to 90° C. and then was held at 90° C. for 2 hours. At the end of 2 hours hold, the solution was cooled down to 45° C. In a separate container, 3.0 grams of Span 80, 29.1 grams of DVB80 with inhibitor stripped off by alumina, acrylamide derived monomer and azobisisobutyronitrile (AIBN) were dissolved and mixed in 63.8 grams of diethyl phthalate. The organic phase was then added to the reactor and the agitation speed was adjusted to 200 rpm with an overhead stirrer. After 30 minutes mixing, the temperature was raised to 70° C. at a ramp rate of 1° C./min; Then the reaction was held at 70° C. for 20 hours then cooled to room temperature. The mixture was filtered and washed 3× with methanol, 3× with THF and finally 3× with methanol. The obtained particles were dried at 45° C. overnight under vacuum. Monomers and analytical data are presented in Table 5. FIG. 8A is a plot of BJH differential surface area (m2/g) vs pore diameter (Å) for the product of Example 9-1. FIG. 8B is a plot of BJH differential pore volume (m3/g) vs pore diameter (Å) for the product of Example 9-1.

TABLE 5

Exam-
DVB
Acrylamide derived monomer

BET
BET

ple
80
Monomer
Charge
AIBN
%
SSA
APD

9
(g)
Name
(g)
(g)
N
(m²/g)
(Å)

1
29.1
4-acryloymorphine
9.21
1.34
1.35
537
138

2
29.1
N-(3-Methoxy-
8.43
1.25
1.26
496
137

propyl)

acrylamide

3
29.1
N,N′-Methylenebis
8.44
1.31
0.93
612
129

(acrylamide

Example 10—Material Using Acrylonitrile Having High Percent N/High Pore Diameter

A 6.0 grams of Celvol 823 and 1.25 grams of sodium dodecyl sulfate (SDS) were charged into a 2 L round bottom flask reactor, followed by an addition of 500 grams of Milli-Q water. The solution was heated to 90° C. and then was held at 90° C. for 2 hours. At the end of 2 hours hold, the solution was cooled down to 45° C. In a separate container, 6.69 grams of 4-acrylonitrile, 29.1 grams of DVB80 with inhibitor stripped off by alumina, 3.0 grams of Span 80 and 1.25 grams of azobisisobutyronitrile (AIBN) were dissolved and mixed in 63.8 grams of diethyl phthalate. The organic phase was then added to the reactor and the agitation speed was adjusted to 200 rpm with an overhead stirrer. After 30 minutes mixing, the temperature was raised to 70° C. at a ramp rate of 1° C./min; Then the reaction was held at 70° C. for 20 hours then cooled to room temperature. The mixture was filtered and washed 3× with methanol, 3× with acetone. The obtained particles were dried at 45° C. overnight under vacuum. % N—4.32; SA—600 m²/g, BET APD—143 Å.

Example 11—Material Using (Meth)Acrylate Derived Monomer Having High Percent N/High Pore Diameter

A 6.0 grams of Celvol 823 and 1.25 grams of sodium dodecyl sulfate (SDS) were charged into a 2 L round bottom flask reactor, followed by an addition of 500 grams of Milli-Q water. The solution was heated to 90° C. and then was held at 90° C. for 2 hours. At the end of 2 hours hold, the solution was cooled down to 45° C. In a separate container, 3.0 grams of Span 80, 29.1 grams of DVB80 with inhibitor stripped off by alumina, (meth)acrylate derived monomer and azobisisobutyronitrile (AIBN) were dissolved and mixed in 63.8 grams of diethyl phthalate. The organic phase was then added to the reactor and the agitation speed was adjusted to 200 rpm with an overhead stirrer. After 30 minutes mixing, the temperature was raised to 70° C. at a ramp rate of 1° C./min; Then the reaction was held at 70° C. for 20 hours then cooled to room temperature. The mixture was filtered and washed 3× with methanol, 3× with THF and finally 3× with methanol. The obtained particles were dried at 45° C. overnight under vacuum. See monomers and analytical data in table. FTIR shows the ester carbonyl band absorbance at ˜1800 cm⁻¹. Results are presented in Table 6.

TABLE 6

Exam-
DVB
(Meth)acrylate derived monomer

BET
BET

ple
80
Monomer
Charge
AIBN
SSA
APD

11
(g)
Name
(g)
(g)
(m²/g)
(Å)

1
29.1
Ethylene Glycol
8.62
1.32
637
126

Dimethacrylate

2
29.1
Methyl Acrylate
7.83
1.26
556
145

Example 12—Material Using 4-Acetoxystyrene Having High Percent N/High Pore Diameter

A 6.0 grams of Celvol 823 and 1.25 grams of sodium dodecyl sulfate (SDS) were charged into a 2 L round bottom flask reactor, followed by an addition of 500 grams of Milli-Q water. The solution was heated to 90° C. and then was held at 90° C. for 2 hours. At the end of 2 hours hold, the solution was cooled down to 45° C. In a separate container, 8.73 grams of 4-acetoxystyrene, 29.1 grams of DVB80 with inhibitor stripped off by alumina, 3.0 grams of Span 80 and 1.32 grams of azobisisobutyronitrile (AIBN) were dissolved and mixed in 63.8 grams of diethyl phthalate. The organic phase was then added to the reactor and the agitation speed was adjusted to 200 rpm with an overhead stirrer. After 30 minutes mixing, the temperature was raised to 70° C. at a ramp rate of 1° C./min; Then the reaction was held at 70° C. for 20 hours then cooled to room temperature. The mixture was filtered and washed 3× with methanol, 3× with acetone. The obtained particles were dried at 45° C. overnight under vacuum. SA—631 m²/g, BET APD—136 Å. FTIR shows the ester carbonyl band absorbance at ˜1800 cm⁻¹.

Example 13 Use of Wide Pore Material Weak Anion Exchanger for the Purification of Oligonucleotides in Plasma

A series of polythymidine oligonucleotides were analyzed for recovery (Table 7) from plasma on material 7 and Comparative Material 2 (2 mg per well in μelution plates—Comparative Material 2 is a representative material from U.S. Pat. No. 7,731,884 having a nominal particle size of 30 μm), according to the following protocol:

a) Condition with 200 μL methanol

b) Equilibrate 200 μL 100 mM NaH₂PO₄2 mM NaN₃in water, pH 5.5

c) Dilute stock oligonucleotide 10:1 with plasma, then:

- i) Dilute plasma/oligomer standard 1:1 with citrate buffer/2 mM NaN₃solution (200 mM citrate 2 mM NaN₃in water, pH 5.5)
  
  or
- ii) Dilute plasma oligomer/standard to make a 10% acetonitrile, 45% plasma/oligomer standard, 45% NaH₂PO₄/2 mM NaN₃solution (100 mM NaH₂PO₄2 mM NaN₃in water, pH 5.5)
  
  d) Load 100 μL of oligo plasma sample (0.4 nmol/mL)

e) Wash 100 μL 1% HCOOH

f) Wash with 100 μL 60% methanol

g) Elute 50 μL*2 30% methanol/70% 30 mM triethylamine in water

h) Elute 100 μL 30% methanol/70% 30 mM triethylamine in water

i) Measure recovery by comparison to standard using a photodiode array.

TABLE 7

Comparison of oligonucleotide recoveries

from plasma for different materials

Polythymidine
Plasma Dilution
Material
%

Oligomer
Step Utilized
Utilized
Recovery

15mer
c i)
Example 7
91

Comp.
50

Material 2

c ii)
Example 7
98

Comp.
63

Material 2

20mer
c i)
Example 7
91

Comp.
45

Material 2

c ii)
Example 7
94

Comp.
39

Material 2

25mer
c i)
Example 7
88

Comp.
33

Material 2

c ii)
Example 7
71

Comp.
13

Material 2

30mer
c i)
Example 7
84

Comp.
20

Material 2

c ii)
Example 7
65

Comp.
6

Material 2

35mer
c i)
Example 7
72

Comp.
11

Material 2

c ii)
Example 7
69

Comp.
5

Material 2

Example 14—Use of Wide Pore Material for the Purification of Proteins

a) A test mixture of several proteins was analyzed for recovery (Table 8) on material 5 g), Comparative Material 1 and Comparative Material 3 (2 mg per well in μelution plates) (Comparative Material 1 is described above; Comparative Material 3 is a representative material from U.S. Pat. No. 5,882,521 having a nominal particle size of 20 μm) and according to the following protocol:

1) Condition plate with 200 μL methanol

2) Condition plate with 200 μL water

3) Load 100 μL diluted protein standard (2.5% ACN and 0.05% TFA in water)

4) Wash with 200 μL 5% methanol in water

5) Elute with 2×25 μL of 3:1 methanol/water with 1% trifluoroethanol

6) Dilute with protein solution for blank and 2.5% acetonitrile and 0.05% TFA in water for sample.

7) Measure recovery by HPLC/UV

TABLE 8

Comparison of protein recoveries for

different materials using protocol a)

Size

(Approx.
[Protein]
Material
%

Peptide
MW)
(mg/mL)
Utilized
Recovery

Insulin
5734
10
Example 5 g)
90

Comp. Material 3
61

Comp. Material 1
30

Cyto-
12384
4
Example 5 g)
39

chrome

Comp. Material 3
2

C

Comp. Material 1
8

Ribo-
13700
4
Example 5 g)
56

nuclease

Comp. Material 3
0

A

Comp. Material 1
0

Myo-
16951
10
Example 5 g)
20

globin

Comp. Material 3
2

Comp. Material 1
2

b) A test mixture of several proteins was analyzed for recovery (Table 9) on material 5 g), Comparative Materials 1 and 3 (2 mg per well in μelution plates, according to the following protocol:

1) Condition plate with 200 μL methanol

2) Condition plate with 200 μL water

3) Load 100 μL diluted protein standard

4) Wash with 200 μL 5% methanol in water

5) Elute with 2×25 μL of 3:1 acetonitrile/water with 5% trifluoroacetic acid

6) Dilute with protein solution for blank and 2.5% acetonitrile and 0.05% TFA in water for sample.

7) Measure recovery by HPLC/UV

TABLE 9

Comparison of protein recoveries for

different materials utilizing protocol b)

Size
[Protein

(Approx.
Standard]

%

Peptide
MW)
(mg/mL)
Material Utilized
Recovery

Insulin
5734
10
Example 5 g)
100

Comp. Material 3
85

Cytochrome C
12384
4
Example 5 g)
93

Comp. Material 3
61

Ribonuclease A
13700
4
Example 5 g)
65

Comp. Material 3
0

Myoglobin
16951
10
Example 5 g)
62

Comp. Material 3
2

β-lactoglobulin
18270
4
Example 5 g)
25

Comp. Material 3
1

Apo-Transferrin
78000
10
Example 5 g)
42

Comp. Material 3
0

Example 10—Monolith Synthesis

The aqueous and organic solutions are prepared as in Example 5, except that no sodium oleyl sulfate is added to the aqueous phase. Following purging of each of the solutions for 10 minutes with Ar, the organic and aqueous phases are combined in small glass vials in the same ratio as in Example 5. Each of the vials is then sealed with a stopper, placed vertically in a thermostated oil bath, heated at 70° C. for 16 hours, and cooled to room temperature.

INCORPORATION BY REFERENCE

The entire contents of all patents, published patent applications and other references cited herein are hereby expressly incorporated herein in their entireties by reference.

EQUIVALENTS

Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, numerous equivalents to the specific procedures described herein. Such equivalents were considered to be within the scope of this invention and are covered by the following claims.

	Number	Date	Country
Parent	14114440	Dec 2013	US
Child	16381881		US

	Number	Date	Country
Parent	16381881	Apr 2019	US
Child	17221471		US

POROUS MATERIALS FOR SOLID PHASE EXTRACTION AND CHROMATOGRAPHY AND PROCESSES FOR PREPARATION AND USE THEREOF

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