Patent Application
20240253002
The invention relates to a composite metal organic framework, to a method of making a metal organic framework, and a method of selecting materials for making a metal organic framework, and to uses of the metal organic framework.
The listing or discussion of a prior-published document in this specification should not necessarily be taken as an acknowledgement that the document is part of the state of the art or is common general knowledge.
The assembly of functional nanomaterials into desired architectures has attracted considerable attention. The properties of these architectures depend on not only the characteristics of individual nanoparticle building blocks, but also the spatial geometry of the assemblies. While nanoparticles of different material composition, shape and size can be precisely engineered to achieve diverse functionalities, their controlled assembly and spatial organization remains a challenging task to realize sophisticated architectures.
Several approaches have been developed to improve the integration control. For example, through colloidal self-assembly, nanoparticles modified with distinct, complementary molecules (e.g., proteins and nucleic acids) can organize themselves via various assembly forces (e.g., attractive and repulsive forces). Despite its high specificity, the approach requires dedicated, sequence-specific modifications and becomes increasingly challenging to multiplex. To improve the incorporation versatility, external templates are used to assemble nanoparticles into hybrid architectures. In particular, metal-organic frameworks (MOFs) may have crystalline structures, uniform cavities and tunable properties, making them an attractive matrix to host nanoparticles. Nevertheless, existing preparation approaches lack spatial precision to control nanoparticle distribution and organization within the frameworks.
Therefore, there is a need for an improved metal organic frameworks with highly controlled nanoparticle distribution and organisation, as well as methods for the preparation of such improved metal organic frameworks.
The inventors have developed a versatile methodology for preparing composite metal organic frameworks comprising particles formed from a surfactant and a nanoparticle and/or proteins. The structure and properties of the composite metal organic framework may be controlled by tuning the interactions of the surfactant with each of the nanoparticle/protein and an organic linker molecule used to form the metal organic framework.
This methodology utilizes surfactants (e.g. amphiphilic surfactants) to guide nanoparticle arrangement during growth of a metal organic framework (MOF). Exploiting the varied interactions of surfactants (polar heads and hydrophobic tails) with MOF constituents and nanoparticles, respectively, the invention allows for precise spatial control of nanoparticle distribution (central vs. peripheral) and organization (clustered vs. dispersed). Through rational selection of surfactants, nanoparticles (and combinations) can be precisely integrated and positioned within various hosts to form different products (e.g., 1D oriented, 3D epitaxial and amorphous). The preparation is fast and safe (<2 min at room temperature, one-pot synthesis with water as the only solvent), and achieves in situ, templated growth on diverse solid substrates.
The invention therefore provides the following numbered clauses.
1. A composite metal organic framework encapsulating one or more populations of particles, wherein a first population of particles comprise:
2. The composite metal organic framework according to Clause 1, comprising a first population of particles and a second population of particles, where the second population of particles comprise:
3. The composite metal organic framework according to Clause 2, wherein:
4. The composite metal organic framework according to Clause 3, wherein:
5. The composite metal organic framework according to any one of Clauses 2 to 4, wherein:
6. The composite metal organic framework according to Clause 5, wherein:
7. The composite metal organic framework according to any one of the previous Clauses, wherein the surfactant of the first population particles, and when present the second population of particles, is independently selected from the group consisting of:
8. The composite metal organic framework according to Clauses 2 to 7, wherein the weight ratio of the first population of particles to the second population of particles ranges from 1:100 to 100:1, optionally from 1:50 to 50:1, more optionally from 1:20 to 20:1, further optionally from 1:10 to 10:1, further optionally still from 1:5 to 5:1, such as from 1:3 to 3:1, for example from 1:2 to 2:1.
9. The composite metal organic framework according to Clause 1, wherein the first population of particles are located within a peripheral portion of the metal organic framework.
10. The composite metal organic framework according to Clause 9, wherein the interaction energy between the surfactant of the first population of particles and the organic linker material of the metal organic framework is greater than −41.8 kJ/mol (−10 kcal/mol).
11. The composite metal organic framework according to Clause 1, wherein the first population of particles are located within a core portion of the metal organic framework, optionally wherein the composite metal organic framework comprises a second population of particles located within a peripheral portion of the metal organic framework.
12. The composite metal organic framework according to Clause 11, wherein the interaction energy between the surfactant of the first population of particles and the organic linker material of the metal organic framework is less than −50.2 kJ/mol (−12 kcal/mol).
13. The composite metal organic framework according to any one of Clauses 1 or 9 to 12 wherein the first population of particles comprises particles mono-dispersed within the metal organic framework.
14. The composite metal organic framework according to Clause 13, wherein the interaction energy between the surfactant and the nanoparticles and/or protein molecules of the first population of particles is less than −83.7 kJ/mol (−20 kcal/mol).
15. The composite metal organic framework according to any one of Clauses 1 or 9 to 12, wherein the first population of particles comprises particles present as particle aggregates within the metal organic framework.
16. The composite metal organic framework according to Clause 15, wherein the interaction energy between the surfactant and the particles and/or protein molecules of the first population of particles is greater than −62.8 kJ/mol (−15 kcal/mol).
17. The composite metal organic framework according to any one of the preceding Clauses, wherein the first population of particles comprises a first set of quantum dots.
18. The composite metal organic framework according to Clause 17 as dependent on any one of Clauses 2 to 8, wherein the second population of particles comprises a second set of quantum dots, optionally wherein the first and second sets of quantum dots are selected from a red quantum dot, a green quantum dot and a blue quantum dot.
19. The composite metal organic framework according to Clause 18, wherein said first set of quantum dots and second set of quantum dots are configured to emit light having different wavelengths.
20. The composite metal organic framework according to any one of Clauses 1 to 16, wherein the first population of particles comprises nanoparticles selected from one or more of the group consisting of an Au nanoparticle (e.g. Au nanosphere, an Au nanorod), a Fe3O4 nanoparticle (e.g. an Fe3O4 nanocube, an Fe3O4 nanosphere), an Ag nanoparticle (e.g. Ag nanosphere), and a CeO2 nanoparticle (e.g. CeO2 nanosphere), optionally wherein the first population of particles comprises nanoparticles selected from one or more of the group consisting of an Au nanoparticle (e.g. Au nanosphere, an Au nanorod), and a Fe3O4 nanoparticle (e.g. an Fe3O4 nanocube, an Fe3O4 nanosphere).
21. The composite metal organic framework according to any one of the preceding Claims, wherein the metal organic framework is a 3-D epitaxial metal organic framework,
22. The composite metal organic framework according to any one of Clauses 1 to 20, wherein the metal organic framework is a 1-D oriented metal organic framework, optionally wherein the 1-D oriented metal organic framework is selected from one or more of the group consisting of Cu-benzene dicarboxylic acid (Cu-BDC), Cu-benzene tricarboxylic acid (Cu-BTC), Ce-benzene dicarboxylic acid (Ce-BDC), and Ce-benzene tricarboxylic acid (Ce-BTC).
23. The composite metal organic framework according to any one of Clauses 1 to 20, wherein metal organic framework is an amorphous metal organic framework, optionally wherein the amorphous metal organic framework is selected from one or more of the group consisting of Fe-benzene dicarboxylic acid (Fe-BDC) and Fe-benzene tricarboxylic acid (Fe-BTC).
24. The composite metal organic framework according to Clause 1, wherein:
25. A method of making a composite metal organic framework encapsulating a first population of particles, said method comprising the steps:
26. The method according to Clause 25, wherein step (b) is performed on or in the presence of a solid substrate (e.g. polystyrene beads, cellulose fibre, copper wire or a glass slide).
27. The method according to Clause 25 or 26, wherein:
28. The method according to Clause 25 or 26, further comprising providing a second population of particles in step (a), and reacting the second population of particles with the first population of particles, metal node material and organic linker material in aqueous solution in step (b), wherein
29. The method according to Clause 28, wherein:
30. The method according to any one of Clauses 25, 26 or 28, wherein the first population of particles comprises nanoparticles selected from one or more of the group consisting of an Au nanoparticle (e.g. Au nanosphere, an Au nanorod), a Fe3O4 nanoparticle (e.g. an Fe3O4 nanocube, an Fe3O4 nanosphere), an Ag nanoparticle (e.g. Ag nanosphere), and a CeO2 nanoparticle (e.g. CeO2 nanosphere), optionally wherein the first population of particles comprises nanoparticles selected from one or more of the group consisting of an Au nanoparticle (e.g. Au nanosphere, an Au nanorod), and a Fe3O4 nanoparticle (e.g. an Fe3O4 nanocube, an Fe3O4 nanosphere).
31. The method according to any one of Clauses 25 to 30, wherein:
32. The method according to Clause 25 or 26, wherein the first population of particles, metal node material, organic linker material, and when present the second population of particles, are selected to provide a composite metal organic framework as defined in Clause 24.
33. The method according to any one of Clauses 25 to 32, wherein when the first, and when present second, populations of particles comprises a nanoparticle, the method comprises preparing the first, and when present second, population of particles by:
34. The method according to any one of Clauses 25 to 33, further comprising the preliminary steps:
35. A method of selecting materials for forming a composite metal organic framework,
36. Use of a composite metal organic framework as defined in any one of Clauses 1 to 24:
37. A composite metal organic framework as defined in Clause 18 or 19 for use in a method of diagnosis, wherein said method of diagnosis comprises:
38. A diagnostic method comprising:
39. A composite metal organic framework according to any one of Clauses 1 to 16 and 21 to 23, wherein the nanoparticle is doxorubicin and/or the protein molecule is bovine serum albumin (BSA).
40. A composite product comprising:
41. A composite product according to Clause 40, wherein the substrate is selected from the group consisting of polystyrene beads, cellulose fibre, copper wire and a glass slide.
42. A pharmaceutical composition comprising a composite metal organic framework according to Clause 1, wherein the inner region of the first population of particles comprises:
The composite metal organic framework of the invention may also be referred to herein as “STAR” (surfactant tunable spatial architecture).
The invention provides a composite metal organic framework encapsulating one or more populations of particles, wherein a first population of particles comprise:
In embodiments herein, the word “comprising” may be interpreted as requiring the features mentioned, but not limiting the presence of other features. Alternatively, the word “comprising” may also relate to the situation where only the components/features listed are intended to be present (e.g. the word “comprising” may be replaced by the phrases “consists of” or “consists essentially of”). It is explicitly contemplated that both the broader and narrower interpretations can be applied to all aspects and embodiments of the present invention. In other words, the word “comprising” and synonyms thereof may be replaced by the phrase “consisting of” or the phrase “consists essentially of” or synonyms thereof and vice versa.
The phrase “consists essentially of” and its pseudonyms may be interpreted herein to refer to a material where minor impurities may be present. For example, the material may be greater than or equal to 90% pure, such as greater than 95% pure, such as greater than 97% pure, such as greater than 99% pure, such as greater than 99.9% pure, such as greater than 99.99% pure, such as greater than 99.999% pure, such as 100% pure.
The composite metal organic framework of the invention is a material in which a metal organic framework encapsulates one or more populations of particles. In other words, a material in which one or more populations of particles are present within a metal organic framework. Thus, as used herein, the term “encapsulated” or “encapsulating” in the context of the composite metal organic framework encapsulating one or more populations of particles means that the particles are present within the metal organic framework.
Metal organic frameworks are well known to a person skilled in the art, and are a class of compounds comprising metal ions coordinated to organic ligands (also known as organic linkers or organic linker material). Metal organic frameworks are typically (but not always) crystalline materials having a regular array of metal ions coordinated to organic ligands.
A first population of the one or more populations of particles comprises an outer shell region formed from a surfactant; and an inner region comprising one or more of a nanoparticle and/or a plurality of protein molecules.
When used herein, the term “nanoparticle” is intended to refer to particles that have an average hydrodynamic diameter of from 0.1 to 2,000 nm. In more particle embodiments of the invention that may be disclosed herein, the nanoparticles may have an average hydrodynamic diameter of from 1 to 1,000 nm, such as from 100 to 400 nm, such as from 120 to 350 nm.
When a composite metal organic framework comprises a plurality of protein molecules, said protein molecules may be individual or aggregated within the inner region of the first population of particles, and may be suspended in the surfactant or present in a micelle.
Without being bound by theory it is believed that, strong interactions between surfactants (primarily the polar heads) and the organic linker material of a metal organic framework drives heterogeneous metal organic framework growth around the readily-incorporated surfactant molecule, while weak interactions favour homogeneous MOF growth and tangential surfactant integration. On the other hand, strong interactions between surfactants (primarily the hydrophobic tails) and nanoparticles stabilize mono-dispersed nanoparticles while weak interactions induce nanoparticle aggregation. It is therefore believed that by the selection of surfactants to tune and mediate these interactions, it is possible to design and guide nanoparticle integration into metal organic frameworks.
Therefore, without being bound by theory it is believed that the location of the particles within the metal organic framework is dependent on the interaction energy between the surfactant and the organic linker material of the metal organic framework as set out below.
Without being bound by theory it is believed that the dispersion state of the particles within the metal organic framework is dependent on the interaction energy between the surfactant and the nanoparticle or protein molecule(s) present at the inner region of the particle as set out below.
In some embodiments of the invention that may be mentioned herein, the location and dispersion state of the particles may generally follow the principles above. In other words, a majority of a population of particles may follow the principles above.
In some embodiments an interaction energy mentioned herein may be determined by simulation using the Quench task of Forcite module using the COMPASS force field with a microcanonical (NVE) ensemble with temperature at 25° C., duration of 50 ps and a time step of 1 fs.
The location and dispersion state of the resulting composite metal organic frameworks is shown graphically in
Thus, in some embodiments of the invention that may be mentioned herein, the first population of particles may be located within a peripheral portion of the metal organic framework. In some such embodiments, the interaction energy between the surfactant of the first population of particles and the organic linker material of the metal organic framework may be weak (e.g. greater than −41.8 kJ/mol (−10 kcal/mol)).
In other embodiments of the invention, the first population of particles may be located within a core portion of the metal organic framework. In some such embodiments, the interaction energy between the surfactant of the first population of particles and the organic linker material of the metal organic framework may be strong (e.g. less than −50.2 kJ/mol (−12 kcal/mol)).
In some embodiments of the invention that may be mentioned herein, the first population of particles may comprise particles mono-dispersed within the metal organic framework. In such embodiments, the surfactant and the nanoparticles and/or protein molecules of the first population of particles may be strong (e.g. less than −83.7 kJ/mol (−20 kcal/mol)).
In other embodiments of the invention, the first population of particles may comprise particles present as particle aggregates within the metal organic framework. In such embodiments, the interaction energy between the surfactant and the nanoparticles and/or protein molecules of the first population of particles may be weak (e.g. greater than −62.8 kJ/mol (−15 kcal/mol)).
In some embodiments of the invention that may be mentioned herein, the one or more populations of particles may comprise a first population of particles and a second population of particles, where the second population of particles comprise:
In some such embodiments, one of the populations of particles (e.g. the first population of particles) may be mono-dispersed within the metal organic framework, and the other population of particles (e.g. the second population of particles) may be present as particle aggregates within the metal organic framework. As explained above, this may be achieved by controlling the interactions between the surfactant and the constituent nanoparticle/protein of the first and second population of particles.
In such embodiments, the interaction energy between the surfactant and the particles and/or protein molecules of the mono-dispersed particles (e.g. the first population of particles) may be strong (e.g. less than −83.7 kJ/mol (−20 kcal/mol)), and the interaction energy between the surfactant and the particles and/or protein molecules of the of the particles present as aggregates (e.g. the second population of particles) may be weak (e.g. greater than −62.8 kJ/mol (−15 kcal/mol)).
In some embodiments of the invention that comprise a first population of particles and a second population of particles, a majority of one of the populations of particles (e.g. the first population of particles) may be located within a peripheral portion of the metal organic framework; and a majority of the other population of particles (e.g. the second population of particles) may be located within a core portion of the metal organic framework.
In such embodiments, the interaction energy between the surfactant of the population of particles located within a peripheral portion of the metal organic framework (e.g. the first population of particles) and the organic linker material of the metal organic framework may be weak (e.g. greater than −41.8 kJ/mol (−10 kcal/mol)), and the interaction energy between the surfactant of the population of particles located within a core portion of the metal organic framework (e.g. the second population of particles) and the organic linker material of the metal organic framework may be strong (e.g. less than −50.2 kJ/mol (−12 kcal/mol)).
As used herein, a “majority” means over 50%, for example over 55%, over 60%, over 65%, over 70%, over 75%, over 80%, over 85%, over 90%, over 95%, over 96%, over 97%, over 98%, or over 99%.
For the avoidance of doubt, when the composite metal organic framework comprises two populations of particles, each population may independently involve strong or weak interactions between the surfactant and both of (i) the organic linker material of the metal organic framework, and (iii) the nanoparticle or protein molecule. In other words, the following combinations are explicitly disclosed.
It will be appreciated that combinations of more than two different kinds of particles is contemplated (e.g. two, three or four) and that these may be derived by analogy from the table above.
In some embodiments of the invention that may be mentioned herein, the surfactant may be selected from the group consisting of:
When the composite metal organic framework of the invention comprises two (or more) populations of particles, the surfactant for each population may independently be selected from those listed above. In such cases, a skilled person would understand that since the surfactant influences the location of the particles within the composite metal organic framework, if two populations are desired to be located in different portions of the composite metal organic framework, they will be selected to have different surfactants. Alternatively, if the populations are desired to be located in the same portion of the composite metal organic framework (e.g. both in the core or both in the periphery), the surfactants may be the same. Furthermore, it is herein explicitly contemplated that a second, third, fourth etc population of particles may have any of the properties defined for the first population of particles in the claims below.
In embodiments of the invention comprising more than one population of particles (e.g. a first population of particles and a second population of particles), the populations may be present at any appropriate weight ratio, such as from 1:100 to 100:1. Thus, the weight ratio of a first population of particles to a second population of particles may be from 1:100 to 100:1, for example from 1:50 to 50:1, from 1:20 to 20:1, from 1:10 to 10:1, from 1:5 to 5:1, from 1:3 to 3:1, or from 1:2 to 2:1.
For the avoidance of doubt, it is explicitly contemplated that where a number of numerical ranges related to the same feature are cited herein, that the end points for each range are intended to be combined in any order to provide further contemplated (and implicitly disclosed) ranges.
For example, the following weight ratio ranges are herein explicitly contemplated from the above.
From 1:100 to 100:1, from 1:100 to 50:1, from 1:100 to 20:1, from 1:100 to 10:1, from 1:100 to 5:1, from 1:100 to 3:1, from 1:100 to 2:1, from 1:100 to 1:2, from 1:100 to 1:3, from 1:100 to 1:5, from 1:100 to 1:10, from 1:100 to 1:20, from 1:100 to 1:50;
In some embodiments of the invention that may be mentioned herein, the first population of particles may comprise a first set of quantum dots. This enables the composite metal framework to act as a sensor. The composite metal framework of the invention may be especially advantageous as a probe/sensor when the one or more populations of particles comprise a first population of particles comprising a first set of quantum dots, and a second population of particles comprising a second set of quantum dots. In such cases, the two sets of quantum dots may be configured to emit light having different wavelengths. For example, the two sets of quantum dots may be independently selected from a red quantum dot, a green quantum dot and a blue quantum dot.
It may be particularly advantageous for the composite metal framework to comprise a first set of quantum dots located in a core region of the metal organic framework, and a second set of quantum dots located in a peripheral region of the metal organic framework. This may enable for a different response to various stimuli, depending on whether or not a stimulus is able to penetrate into the core region of the metal organic framework and/or whether a stimulus is able to selectively quench fluorescence of the first or second set of quantum dots. For example, if a stimulus is not able to penetrate into the metal organic framework then it may modulate a signal from a quantum dot located at the periphery of the metal organic framework, while a quantum dot located at the core of the metal organic framework acts as a reference signal. A specific example of such sensing may be the detection of hydrogen peroxide, which may quench the fluorescence of quantum dots. Thus, the metal organic frameworks may be used to detect the presence of biomarkers that are able to generate quenching molecules (e.g. hydrogen peroxide) in the presence of an appropriate substrate (e.g. lectin-oxidase).
In some embodiments of the invention that may be mentioned herein, the first population of particles may comprise nanoparticles selected from one or more of the group consisting of an Au nanoparticle (e.g. Au nanosphere, an Au nanorod), a Fe3O4 nanoparticle (e.g. an Fe3O4 nanocube, an Fe3O4 nanosphere), an Ag nanoparticle (e.g. Ag nanosphere), and a CeO2 nanoparticle (e.g. CeO2 nanosphere). In some such embodiments, the first population of particles may comprise nanoparticles selected from one or more of the group consisting of an Au nanoparticle (e.g. Au nanosphere, an Au nanorod), and a Fe3O4 nanoparticle (e.g. an Fe3O4 nanocube, an Fe3O4 nanosphere).
In some embodiments of the invention that may be mentioned herein, the first population of particles may comprise nanoparticles that compromise a pharmaceutical compound, such as a small molecule active agent, e.g. doxorubicin.
In some embodiments of the invention that may be mentioned herein, the first population of particles may comprise a protein, such as bovine serum albumin (BSA).
As will be appreciated by a person skilled in the art, the second (or further) populations of nanoparticles, when present, may be selected from the same options as the first set of nanoparticles.
The metal organic framework may be any suitable metal organic framework, such as a 3-D epitaxial metal organic framework, a 1-D oriented metal organic framework, or an amorphous metal organic framework. Suitable examples of 3-D epitaxial metal organic frameworks include zeolitic imidazolate frameworks (ZIFs), such as ZIF-8 or ZIF-67, for example ZIF-8. Suitable examples of 1-D oriented metal organic frameworks include Cu-benzene dicarboxylic acid (Cu-BDC), Cu-benzene tricarboxylic acid (Cu-BTC), Ce-benzene dicarboxylic acid (Ce-BDC), and Ce-benzene tricarboxylic acid (Ce-BTC). Suitable examples of amorphous metal organic frameworks include Fe-benzene dicarboxylic acid (Fe-BDC) and Fe-benzene tricarboxylic acid (Fe-BTC).
Specific examples of composite metal organic frameworks according to the invention are those in which:
The composite metal organic framework of the invention may be utilised on a substrate. Thus, the invention provides a composite product comprising:
In some embodiments of the invention, the substrate may be selected from the group consisting of polystyrene beads, cellulose fibre, copper wire and a glass slide.
The invention also provides a method of making a composite metal organic framework encapsulating a first population of particles, the method comprising the steps:
The metal organic framework and first population of particles may have any property defined above.
In some embodiments of the invention that may be mentioned herein, step (b) may be performed on or in the presence of a solid substrate (e.g. polystyrene beads, cellulose fibre, copper wire or a glass slide).
In some embodiments of the invention that may be mentioned herein, the method may involve a second population of particles. Thus, the method may comprise providing a second population of particles in step (a), and reacting the second population of particles with the first population of particles, metal node material and organic linker material in aqueous solution in step (b), wherein
The metal node material may be selected from any appropriate metal node for forming a metal organic framework. Thus, in some embodiments of the invention that may be mentioned herein, the metal node material may be selected from one or more of the group consisting of Zn2+, Co2+, Cu2+, Fe3+, and Ce3+. Specific compounds that may be useful in the method of the invention include Zn(NO3)2, CoCl2, CuSO4, FeCl3, and Ce(NO3)3.
The organic linker material may be selected from any appropriate organic linker material for forming a metal organic framework. Thus, in some embodiments of the invention that may be mentioned herein, the organic linker material may be selected from one or more of the group consisting of 2-methylimidazole (HMIM), benzene-1,4-dicarboxylic acid (BDC) and benzene-1,3,5-tricarboxylic acid (BTC).
When the first, and when present second, populations of particles comprises a nanoparticle, the method may comprise preparing the first, and when present second, population of particles by:
As discussed herein, the interaction energies between the surfactant and each of the organic linker material of the metal organic framework, and the nanoparticle or protein molecule, are believed to influence the resulting structure of the composite metal organic framework. This allows the species in question to be selected to provide the first, and when present second or further, populations of particles in a desired dispersion state and location of the metal organic framework. Thus, in some embodiments of the invention that may be mentioned herein, the method may comprise the preliminary steps:
The invention also provides a method of selecting materials for forming a composite metal organic framework,
In the above methods involving the selection of materials for forming a composite metal organic framework, the interaction energies between the surfactant and other components may be determined by simulation using the Quench task of Forcite module using the COMPASS force field with a microcanonical (NVE) ensemble with temperature at 25° C., duration of 50 ps and a time step of 1 fs.
As discussed in more detail herein, the composite metal organic framework of the invention may be utilised in a number of applications, for example:
Suitable components for each of these uses will be apparent to a skilled person from the present disclosure, in particular the below Examples.
The composite metal organic framework may also be useful in a method of diagnosis, particularly when the composite metal organic framework comprises two populations of particles: a first population of particles comprising a first set of quantum dots, and a second population of particles comprising a second set of quantum dots. Such composite metal organic frameworks may be useful in a method of diagnosis, wherein said method of diagnosis comprises:
The invention also provides a diagnostic method utilising such metal organic frameworks, for example a diagnostic method comprising:
The invention also provides a pharmaceutical composition comprising a composite metal organic framework according to the invention, wherein the inner region of the first population of particles comprises:
The invention is illustrated by the below Examples, which are not to be construed as limitative.
In the following Examples, the composite metal organic framework of the invention is also referred to as “STAR” (surfactant tunable spatial architecture).
All chemicals used for synthesis and modification were purchased from Sigma-Aldrich and used directly, unless otherwise stated. Dulbecco's modified Eagle's medium (DMEM) and vesicle-depleted fetal bovine serum (dFBS) were purchased from HyClone. Penicillin-streptomycin was purchased from Corning. Polydimethylsiloxane (PDMS) was purchased from Dow Corning. Phosphate buffered saline (PBS) and biotinylated lectins were purchased from Vector Laboratories. Anti-CD24 antibody was purchased from eBioscience of Thermo Fisher Scientific.
DLS analysis of particle diameter and zeta potential was performed with Zetasizer Nano ZS instrument (Malvern).
PXRD was performed in the 26 range 5-50° at a scanning rate of 2° min−1 on an X-ray diffractometer (Bruker D8 Advanced) with a Cu-Kα radiation at 40 KV and 40 mA.
For SEM analysis, samples were loaded on silicon slides, sputter-coated with gold (Leica) before being examined (JEOL 6701).
For TEM analysis, samples were loaded onto carbon-coated copper grids (Latech) for imaging (JEOL 2010F).
All measurements were performed in triplicate, and the data are displayed as mean±standard deviation. Correlations were performed with linear regression to determine the goodness of fit (R2). For inter-sample comparisons, multiple pairs of samples were analyzed by two-tailed t-test, and the resulting P values were adjusted for multiple hypothesis testing using Bonferroni correction. For unsupervised hierarchical clustering analysis, STAR profiling of glycan signatures were clustered using Euclidean distance metric and complete linkage (Morpheus, Broad Institute). The lectin markers were grouped into two clusters, according to patient expression profiles. Principal component analysis was performed using Minitab (v.16.1) based on a combination of significant lectin markers to categorize the patient samples according to their clinical prognosis. All other statistical analyses were performed using GraphPad Prism (v. 7.0c).
Au NS was synthesized by rapidly injecting gold precursors into a pre-heated surfactant solution (Peng, S. et al., Proc. Natl. Acad. Sci. USA 2010, 107, 14530-14534). Briefly, oleylamine (5 ml) was refluxed at 150° C. under nitrogen. A mixture of HAuCl4·3H2O (0.3 mmol) in oleylamine (1 ml) was rapidly injected into the hot solution and stirred for 1.5 h. The obtained Au NS was washed by ethanol and dispersed in chloroform for further use.
Au NR was prepared via a seed-mediated growth method (Nikoobakht, B. & El-Sayed, M. A., Chem. Mater. 2003, 15, 1957-1962). Spherical gold seeds were newly synthesized by vigorously mixing ice-cold NaBH4 (0.01 M, 0.6 ml) and an aqueous solution (7.5 ml) containing CTAB (0.1 M) and HAuCl4 (0.3 mM). After 5 s of mixing, the seed solution was ready for further use. Au NR were synthesized in a water bath at 29° C. CTAB (5 ml, 0.2 M) was mixed with AgNO3 solution (4 mM, 0.25 ml), HAuCl4 (1 mM, 5 ml) and ascorbic acid (70 μl, 78.8 mM). The seed solution (12 μl) was then added to the growth solution and allowed to grow overnight. The obtained Au NR was further purified using CTAB (Jana, N. R., Chem. Commun. 2003, 1950-1951) and stored in water for further use.
Iron Oxide Nanosphere (Fe3O4 NS)
Fe3O4 NS was synthesized according to a published method (Park, J. et al., Nat. Mater. 2004, 3, 891-895). Fe-oleate complex was first prepared by reacting metal and sodium oleate. The Fe-oleate complex (3.6 g) and oleic acid (1.0 g, 90%) were dissolved in 1-octadecene (10 ml, 90%) at room temperature. The reaction mixture was heated to 320° C. for 30 min under nitrogen atmosphere. The particles were precipitated using ethanol, and dispersed in chloroform.
Fe3O4 Nanocube (Fe3O4 NC)
Fe3O4 NC was prepared through thermal decomposition of Fe-oleate precursors (Muro-Cruces, J. et al., ACS Nano 2019, 13, 7716-7728). In a typical experiment, 1-octadecene (5 ml) solution containing Fe-oleate (2 g) and sodium oleate (2.2 g, 82%) was heated to 320° C. and refluxed for 60 min to allow nanocube growth. The particles were precipitated using ethanol, and dispersed in chloroform.
CeO2 Nanosphere (CeO2 NS)
CeO2 NS was prepared through thermal decomposition of cerium nitrate (Lee, S. S. et al., Chem. Mater. 2012, 24, 424-432). Briefly, Ce(NO3)3·6H2O (0.108 g, 0.25 mmol) and oleylamine (0.802 g, 3.0 mmol) were dissolved in 1-octadecene (4 ml) at 80° C. The resultant mixture was then heated to 260° C. for 2 h. The particles were precipitated using ethanol, and dispersed in chloroform.
Ag NS was prepared by dissolving AgNO3 (51 mg, 0.30 mmol) in oleylamine (7.5 mmol, 2.5 ml) which was then injected quickly into refluxing toluene (50 ml, Hiramatsu, H. & Osterloh, F. E., Chem. Mater. 2004, 16, 2509-2511). The reaction was left at reflux overnight, before being cooled. The particles were precipitated using ethanol, and dispersed in chloroform.
To stabilize hydrophobic nanoparticles in aqueous media, surfactant modification was performed through phase transfer reactions. Briefly, the as-synthesized nanoparticles in Example 1 were dispersed in organic solvent (0.5 ml, 5 mg/ml), and mixed with aqueous surfactant solutions (0.5 ml). The mixture was sonicated for 3 min and organic solvent was evaporated at 80° C. The resultant suspension was filtered to remove excess free surfactants.
QD NP were prepared according to reported methods (Chen, D. et al., Chem. Mater. 2010, 22, 1437-1444; and Bae, W. K. et al., Chem. Mater. 2008, 20, 531-539).
For the synthesis of blue QDs (BQD), preliminarily, S precursor solution (0.1 M) was prepared using S powder and 1-octadecene, and Zn precursor solution (0.1 M) was prepared by dissolving ZnO and oleic acid (1:8 molar ratio) in 1-octadecene. To synthesis CdS core, a mixture of CdO (0.2 mmol), oleic acid (1.6 mmol), and 1-octadecene (6 g) was heated to become clear at 260° C. and then S precursor solution (1 ml) was rapidly injected. After 30 min, the reaction mixture with formed CdS nanocrystals was cooled down to 50° C. Then, methanol was used to remove unreacted precursors and side products. To grow the ZnS shell, oleylamine (2 ml) was added to the CdS core solution and heated to 120° C. The Zn and S precursor solutions (1 ml each) were added consecutively. The temperature was increased immediately to 220° C. and kept for 20 min to allow the growth of ZnS shell.
For typical synthesis of green QDs (GQD) and red QDs (RQD), CdO and zinc acetate were dissolved in oleic acid (5 ml) at elevated temperature 150° C. under nitrogen protection. 1-octadecene (10 ml) was then added and the temperature was increased to 310° C. Finally, a stock solution containing trioctylphosphine (3 ml), Se powder and S powder was quickly injected into the reaction. The reaction was maintained at 310° C. for 10 min before cooling to room temperature. The initial precursor compositions corresponding to GQD and RQD were (Cd: 0.4 mmol; Zn: 4 mmol; Se: 0.1 mmol; S: 4 mmol) and (Cd: 0.4 mmol; Zn: 4 mmol; Se: 1 mmol; S: 2.3 mmol), respectively. The product was collected and dispersed in chloroform.
All reactions were performed in water and at room temperature. Surfactant-stabilized nanoparticles (5 mg/ml, prepared in Example 2), metal nodes including Zn(NO3)2 (0.05 M), COCl2 (0.05 M), CuSO4 (0.025 M), FeCl3 (0.025 M) and Ce(NO3)3 (0.025 M), as well as organic linkers including HMIM (2.5 M), benzene-1,4-dicarboxylic acid (BDC, 0.025 M) and benzene-1,3,5-tricarboxylate (BTC, 0.025 M), were used for different STAR assemblies, unless otherwise stated. BDC and BTC were dissolved in water, with the addition of NaOH, and the final solution was kept at pH 6-7. Taking (Au-Tween 20)-(ZIF-8) for example, Tween 20-stabilized Au nanoparticles (2.5 μl) were mixed with Zn(NO3)2 (50 μl), followed by the addition of HMIM (50 μl). After vigorous mixing, the mixture was allowed to react in static for 10 min. The product was collected through centrifugation and washed by deionized water. All other composites were prepared in a consistent approach.
To examine the spatial distribution of nanoparticles in MOF host, the prepared composites were washed in situ on TEM grid. Specifically, STAR solution (10 μl) was first deposited on a TEM grid for 5 min. Following gentle removal of the suspension, wash buffers of various pH (10 μl) was dropped and incubated on the grid, before being wicked away with a piece of filter paper. The prepared grid was finally dried for further TEM analysis, to evaluate the remaining nanoparticle distribution and morphology in MOF structures, so as to optimize the wash conditions.
Surfactants are amphiphilic and demonstrate distinct interactions with MOFs and nanoparticles, respectively (Dederichs, T., Möller, M. & Weichold, O., Langmuir 2009, 25, 10501-10506; and Liu, X.-Y. et al., Nano Lett. 2020, 20, 1774-1780). We thus leveraged surfactants to mediate and guide nanoparticle integration into MOF hosts, to achieve precise control of nanoparticle organization and spatial distribution in STARs (
In developing the STAR synthesis, we first evaluated the surfactant effects on MOFs and nanoparticles, respectively.
Molecular dynamics simulations between surfactants and MOF constituents were performed, in a surfactant-constituent pairwise manner, through a commercial software (Materials Studio 2018). We simulated interactions between the surfactant heads and the constituent molecules. For ionic surfactants, interactions were studied with and without counter ions. All molecular structures were modeled by sketch tools and geometrically optimized. The intermolecular interactions were simulated through the Quench task of Forcite module using the COMPASS force field with a microcanonical (NVE) ensemble. For each surfactant-constituent pair examined, three different molecular dynamics simulations were carried out: surfactant-constituent complex, surfactant only, and constituent only. The interaction energy (Es/c) is calculated as Es/c=Es+c−(Es+Ec), where Es+c, Es and Ec are the potential energies of surfactant-constituent complex, surfactant only, and constituent only, respectively. All simulations were set with the following parameters: temperature at 25° C., duration of 50 ps with a time step of 1 fs. Simulation data collected in the last 40 ps were used for structural and statistical analysis.
We utilized different surfactant modifications to tune and direct various nanoparticle assembly and distribution in different MOF hosts. To achieve the desired nanoparticle distribution, we selected respective surfactants, according to their interaction profiles as predicted by the molecular dynamics simulations. For the integration of a single type of nanoparticles, we regulated the loading ratio of different surfactant-modified nanoparticles to control their spatial distributions. For example, to prepare Au-ZIF-8, Au-Tween 20 and Au-CTAB (2 μl, 5 mg/ml) were independently prepared, and mixed with Zn2+ solution (50 μl, 0.05 M). The solutions were added in various proportions to HMIM (50 μl, 2.5 M). After vigorous mixing, the reaction was allowed to react in static for 10 min. The prepared composites were collected through centrifugation and characterized for spatial distribution. For the integration of multiple types of nanoparticles, to achieve the desired spatial distribution, we matched the nanoparticles with different surfactant modifications. For example, to prepare (Au, Fe3O4)-ZIF-8 composite with monodispersed Au locating peripherally (outside) and aggregated Fe3O4 encapsulated centrally (inside) of the MOF host, Au-Tween 20 and Fe3O4-CTAB (2 μl, 5 mg/ml) were independently prepared, mixed with Zn2+ solution (50 μl, 0.05 M), and added in various proportions to HMIM solution (50 μl, 2.5 M). After vigorous mixing, the reaction was allowed to react in static for 10 min. The prepared composites were collected through centrifugation and characterized for spatial distribution.
Using ZIF-8 and Au nanospheres as a model system (
We next investigated the surfactant effects in preparing different STARs. We prepared Au nanospheres with different surfactant coating before mixing them with MOF constituents (HMIM and Zn2+) by following the protocol in Example 4.
To quantify nanoparticle concentration in the as-synthesized STAR assembly (Ntotal), we measured its elemental content by inductively coupled plasma-optical emission spectrometry (ICP-OES) (Perkin Elmer Avio 500). The nanoparticle spatial distribution in MOF was evaluated through in situ washes, as described in Example 5. As the wash buffer infiltrates the MOF structure, it first dislodges the peripherally-associated nanoparticles (outside) from the MOF host; the centrally-encapsulated nanoparticles (inside) remain within the MOF host. The wash conditions were optimized through TEM characterization to achieve clear differentiation of the outside population: acidic HCl buffers (pH=4.0) were used for HMIM-based and BTC-based samples, and alkaline NaOH buffers (pH=9.0) were used for BDC-based samples. All wash incubations were kept to 5 min. To quantify nanoparticles dislodged into the supernatant (Noutside), after in situ washes, we recovered the supernatant and quantified its elemental content through ICP-OES.
The nanoparticle spatial distribution in STAR assembly is determined as below:
ρoutside=Noutside/Ntotal
ρinside=1−ρoutside
Where ρoutside and ρinside are fractions of nanoparticles distributed outside and inside of the STAR assembly, respectively. Ntotal is the total number of nanoparticles in the STAR assembly.
Noutside is the number of peripherally-associated nanoparticles, dislodged into the supernatant after in situ washes.
In all cases, STARs formed rapidly upon reagent mixing (
To evaluate the versatility of the surfactant-guided assembly, we expanded the strategy in Example 4 to prepare different STARs using diverse nanoparticles of different sizes, shapes and materials with various MOF hosts, including another 3D epitaxial MOF (ZIF-67), 1D-oriented MOFs (Cu-BDC, Cu-BTC, Ce-BDC and Ce-BTC) as well as amorphous products (Fe-BDC and Fe-BTC). Nanoparticle spatial distribution with respect to the MOF host was performed by following the protocol in Example 7.
TEM characterization verified that across all tested nanomaterials, the organization and distribution of nanoparticles within the STARs were consistent with the predicted architectures (
Inspired by its universality, we exploited the approach to design and develop complex architectures. Using Au nanospheres coated with Tween 20 and CTAB, respectively, we varied the loading ratio of these nanoparticle populations. The approach achieved precise spatial tuning of nanoparticle distribution within individual MOFs; the STAR morphology correlated well with the initial nanoparticle loading ratio and matched closely to the designed architecture (
We next employed this approach of surfactant matching to precisely integrate and distribute different types of nanoparticles in STARs. Using Au and Fe3O4 nanoparticles of different sizes and shapes, we coated them with Tween 20 and CTAB to develop multi-particle architectures (
To apply STARs for various biotechnology applications, we first evaluated the robustness of their preparation in solution and on solid substrates. Using different nanoparticles and MOF hosts, we prepared STARs as a suspension through aqueous synthesis (
To evaluate cellular toxicity, we employed the MTS cell proliferation assay (Thermo Scientific). Per manufacturer's protocol, epithelial cells (A431) were seeded and incubated with different concentrations of STAR composites for 24 h. After the addition of MTS reagent, absorbance (490 nm) was measured to evaluate cell viability (Tecan).
To integrate DOX and BSA into the RQD-ZIF-8 STAR assembly, Tween 20-stabilized RQD nanoparticles (5 mg/ml, 2.5 μl) were mixed with Zn(NO3)2 (0.05 M, 50 μl), followed by the sequential addition of BSA (10 mg/ml, 4 μl), DOX (10 mg/ml, 2 μl), and HMIM (2.5 M, 50 μl). After vigorous mixing, the mixture was allowed to react in static for 10 min. All solutions were prepared with distilled water.
STAR assemblies were grown in situ on various substrates at room temperature. Briefly, surfactant-modified nanoparticles, metal node solution and organic linker solution were mixed and loaded immediately onto substrates (e.g., polystyrene, metal, cellulose, glass). After 10 min of incubation, the substrates were washed in water to remove unbound composites and dried for further characterization. The synthesis precursors for different substrates are as follows: polystyrene beads: Zn2+ node (50 mM, 0.5 ml), HMIM (2.5 M, 0.5 ml), RQD-Tween 20 (5 mg/ml, 25 μl); copper wire: Co2+ node (50 mM, 0.5 ml), HMIM (2.5 M, 0.5 ml), Fe3O4 nanocube-SDS (5 mg/ml, 25 μl); cellulose fibre: Zn2+ node (25 mM, 0.5 ml), HMIM (2.5 M, 0.5 ml), RQD-Tween 20 (5 mg/ml, 25 μl); glass slide: Ce3+ node (25 mM, 0.5 ml), BDC (25 mM, 0.5 ml), GQD-Tween 20 (5 mg/ml, 25 μl).
The reaction could be completed in <2 min at room temperature, with water as the only solvent. Importantly, the reaction achieved controlled nanoparticle loading and yielded a high nanoparticle integration efficiency (>90%) to form composites with different properties (
We further assessed the assembly of STARs on various solid substrates (e.g., polystyrene microspheres, cellulose mesh, copper wire) (
We next applied STARs, prepared in solution or on substrates, for various biotechnology applications. Using differentially-coated Au nanoparticles and ZIF-8 as a host, we prepared STARs with varied spatial distribution of nanoparticles, dispersed vs. encapsulated. We applied these two types of STARs as nanocatalysts for the reduction of 4-NP to 4-AP (
Two Au-ZIF-8 composites with distinct Au nanoparticle distributions (i.e., peripherally dispersed Au-Tween 20 and encapsulated Au-CTAB) were adopted as catalysts for the conversion of 4-NP to 4-AP in the presence of reductive NaBH4. The Au-ZIF-8 composites were synthesized using Au nanoparticles (2.5 μl, 5 mg/ml), Zn(NO3)2 (50 μl, 0.05 M), and HMIM (50 μl, 2.5 M) by following the protocol in Example 4. For the analysis of catalytic efficiency, 4-NP (0.25 ml, 1 mM, pH=10) and freshly prepared aqueous NaBH4 (0.25 ml, 50 mM) were mixed in 3.5 ml of water. Subsequently, Au-ZIF-8 composites (0.1 ml, 5 mg/ml) were added to the reaction. UV-Vis absorption spectra were recorded in real time to monitor the concentration of 4-NP (Tecan).
A PMMA array with 5×17 wells was prepared via a tabletop CO2 laser engraver (Universal Laser Systems). We employed microscopic (STAR assemblies) and macroscopic patterning (well positioning) to encrypt information (Table 1). For microscopic encryption, various STAR assemblies were synthesized; these assemblies contain combinations of nanoparticles, differentially distributed in various MOF hosts. For macroscopic patterning, different STAR assemblies were mixed with polyacrylamide gel precursor (4% PAGE gel, Bio-Rad) and allowed to polymerize in defined wells. To achieve information transformation, the device was treated with 2% acetic acid as the stimulus for 10 min, before being washed in water, to reveal the encrypted code.
To reveal latent fingerprints on a solid surface, MOF constituents (Ce3+ and BDC) and RQD stabilized by Tween 20 were applied immediately onto the surface. Specifically, a reaction mixture comprising Ce3+ node (25 mM), BDC (25 mM), and RQD-Tween 20 (5 mg/ml), mixed in a volumetric ratio of 100:100:1, was applied to the surface. After a quick incubation (5 min at room temperature), the unbound materials were flushed with water. The fingerprint-induced STAR patterning could be visualized under UV excitation (365 nm).
By absorbance measurement, we demonstrated that the dispersed STARs have a higher catalytic efficiency than the encapsulated form (
Drawing on the advantages above, we developed complementary STARs for various biotechnology applications. In particular, we developed a dual-probe STAR to achieve direct profiling of extracellular vesicle (EV) glycans in clinical specimens (
To streamline the assay workflow, we synthesized the STARs in a miniaturized microfluidic device and performed EV glycan measurements on-chip (
A prototype dual-layer microfluidic device (
Operation steps are illustrated in
All fluorescence signals are calculated relative to the central reference population (RQD):
where IG and IR are the fluorescence intensities of GQD and RQD, respectively.
For glycosylation analysis, the signal response is determined as below:
where So and Ss are the fluorescence signals before and after sample incubation, respectively.
To enable smartphone-based evaluation of the STAR assay, we developed a sensor 500 consisting of five components (
The dual-probe STAR developed in Example 11 was taken for the direct profiling of EV glycans in clinical biofluids. Specifically, the architecture contained two different types of QDs spatially organized within the assembly: RQD clustered centrally and GQD associated peripherally as dispersed entities. We grew the dual-probe STARs on a microfluidic platform and utilized their intra-assembly spatial distribution of nanoparticles (and hence different responsiveness) to develop the EV glycan assay (
EVs derived from human brain glial cells (GLI36) and skin epithelial (A431) were collected through gradient centrifugation. Cells were cultured in DMEM supplemented with 5% dFBS, and penicillin-streptomycin. The culture medium was filtered through a 0.8-μm membrane filter (Millipore) and pelleted at 10,000 g for 20 min to deplete cell debris. The supernatant was centrifuged at 100,000 g for 2 h to concentrate EVs. Collected EVs were analyzed through nanoparticle tracking analysis (NTA) system (NS300, Nanosight) to quantify their size distribution and concentration. All NTA measurements were performed with identical system settings, with ˜ 50 vesicles in the field of view to achieve optimal counting. For TEM analysis of EVs, samples were fixed with 2% paraformaldehyde, loaded onto a copper grid (Latech), and contrast-stained with uranyl oxalate and methyl cellulose mixture before TEM analysis.
Samples were adsorbed onto ELISA plates (Thermo Scientific) and blocked using PBS containing 1% BSA. After washing, biotinylated lectins (5 μg/ml) were introduced in PBS containing 1% BSA. Following incubation (1 h at room temperature), streptavidin-conjugated GQD-ZIF-8 probes were added. Fluorescence signal was determined through a commercial plate-reader (Tecan).
The STARs showed minimal nanoparticle leaching during the assay (
Triticum vulgaris
agglutinin
Dolichos biflorus
Ulex europaeus
Ricinus communis
Arachis hypogaea
Griffonia (Bandeiraea)
simplicifolia lectin I
Pisum sativum
Lens culinaris
Phaseolus vulgaris
Erythroagglutinin
Phaseolus vulgaris
Leucoagglutinin
Sophora japonica
Griffonia (Bandeiraea)
simplicifolia lectin II
Datura Stramonium
Erythrina cristagalli
Artocarpus integrifolia
Lycopersicon
esculentum (tomato)
Solanum tuberosum
Vicia villosa agglutinin
Sambucus Nigra
Maackia Amurensis
Aleuria aurantia lectin
Galanthus nivalis
Finally, we conducted a feasibility study using colorectal cancer patient ascites. Using STARs functionalized with antibodies, we developed the assay to achieve direct glycan profiling of cancer-associated EVs in patient specimens, as described in Example 11. Specifically, we prepared STARs with antibodies against CD24 (Wang, Z. et al., Matter 2020, 2, 150-166; and Im, H. et al., Nat. Biotechnol. 2014, 32, 490-495), a known cancer antigen, to enrich and measure putative tumor-derived EVs.
The study was approved by the National University Hospital (2016/01088), and SingHealth (2015/2479) Institutional Review Boards. All subjects were recruited according to IRB-approved protocols after obtaining informed consent. Ascites samples were collected from colorectal cancer patients, centrifuged at 500 g for 10 min, and filtered through a 0.8-μm membrane filter (Millipore). All samples were de-identified and stored at −80° C. before glycan analysis.
Functionalisation of STAR Assemblies with Antibodies
The preparation of STAR assembly follows the protocol in Example 4. The STAR assembly was then incubated with antibody solution (2 μg/ml) for 1 h at room temperature to allow the immobilization of antibody molecules on the STAR assembly. After washing with PBS buffer, the STAR assembly was blocked with BSA solution (10 mg/ml) for further analysis.
For clinical analysis, ascites samples were used directly. To enable selective measurement of glycan signatures on EVs, we first functionalized STAR assemblies with antibodies against CD24, through electrostatic attraction and thiol-zinc affinity. Following antibody modification and subsequent BSA blocking, ascites samples (5 μl) were introduced for direct analysis, as described in Example 11. All STAR measurements were performed relative to respective sample-matched and no-lectin control. Clinical evaluation of patient characteristics was determined independently. Specifically, patient prognosis was determined by the overall survival from the time of collection of ascites. Patients were deemed to have a good prognosis when the overall survival was more than ten months. Conversely, patients were determined to have a poor prognosis if the overall survival was less than five months. All STAR measurements were performed blinded from these clinical evaluations.
Multiplexed glycan profiling showed highly varied glycan signatures among the clinical samples (
The invention is able to provide a high degree of control over both the spatial control and integration versatility of nanoparticles/protein molecules within metal organic frameworks. This allows for a diverse range of nanotechnology applications as disclosed herein.
With respect to spatial control, the invention utilises surfactants to guide nanoparticle integration while moulding the growing framework. Unlike conventional approaches which either modify nanoparticles or template framework development, the invention leverages surfactant interactions to tune both simultaneously. Specifically, strong interactions between surfactants and metal organic framework constituents drive central integration and heterogeneous framework growth while weak interactions induce peripheral integration and homogeneous framework; likewise, strong interactions between surfactants and nanoparticles stabilize nanoparticles while weak interactions lead to clustered nanoparticles. The approach utilised by the invention is thus programmable and predictable from the general principles disclosed herein, and yields a high nanoparticle integration efficiency (>90%). It not only tunes the overall morphology but also achieves intra-assembly spatial control—nanoparticle organization and distribution—to develop hybrid architectures.
With respect to integration versatility, the approach can be readily expanded to assemble different nanomaterials with various hosts (e.g., 1D oriented, 3D epitaxial and amorphous metal organic frameworks). Importantly, unlike conventional synthesis approaches which require harsh chemicals and lengthy processing, the invention enables these composite metal organic framework to be prepared quickly and safely (<2 min aqueous synthesis at room temperature). The invention can therefore be adopted to integrate sensitive, biological molecules (e.g., proteins and small molecule drugs) and to achieve in situ growth on different types of solid substrates, to develop various multifunctional assemblies for diverse applications.
The invention also enables the design and development of metal organic frameworks comprising a number of different nanomaterials, each precisely positioned with respect to one another by rational surfactant selection.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10202105866S | Jun 2021 | SG | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/SG2022/050377 | 6/2/2022 | WO |
