Patent Application
20240100523
The subject matter relates to dispensing liquids and more particularly to digital microfluidics (DMF) devices and methods for dispensing liquids using piercer features and compressible membranes.
A DMF cartridge (or device) typically includes one or more substrates with a gap therebetween. For example, the one or more substrates establish a droplet operations surface or gap for conducting droplet operations. The substrates may also include electrodes arranged to conduct the droplet operations. The droplet operations substrate or the gap between the substrates may be coated or filled with a filler liquid that is immiscible with the liquid that forms the droplets. Loading reagents and oil into a DMF cartridge has been highlighted as one of the most difficult steps in performing a DMF experiment. Accordingly, new approaches are needed with respect to loading liquids, such as sample liquid, reagents, and oil, into DMF cartridges.
The disclosure provides a microfluidics cartridge. The cartridge may include a top substrate and a bottom substrate separated to form a droplet operations gap, the top substrate including a well plate including an array of wells each well including a hollow needle liquidly connecting an interior of the well with the droplet operations gap. The cartridge may include a compressible membrane layer atop the well plate sealing the reservoirs and arranged so that compression of the flexible membrane towards the interior of the well forces a liquid from the interior of the well through the hollow needle, and into the droplet operations gap.
The disclosure provides a system including a cartridge mounted on an instrument. The instrument may include processors, controllers, electronics, optics, and the like for interfacing with the cartridge. The instrument may include a means for compressing the flexible membrane. The means may be electrically coupled to and controlled by a computer processor of the instrument.
The cartridge may include a DMF portion including: a bottom substrate and a top substrate, each having a bottom surface and a top surface, wherein the top substrate contains one or more openings through which a liquid can flow; one or more pairs of piercer features extending upwards from the top surface of the top substrate, wherein the pair of piercer features are separated by a gap, thereby forming a flow channel therethrough, and wherein the flow channels are in substantial alignment with the openings; and a droplet operations gap interposed between the top surface of the bottom substrate and the bottom surface of the top substrate, thereby separating the bottom substrate and the top substrate to form a chamber in which droplet operations can be performed, wherein the flow channels are in liquid contact with the droplet operations gap via the openings.
The cartridge may include a well plate portion including: a compressible membrane layer having a top surface and a bottom surface, wherein the bottom surface is mounted on the top surface of the top substrate; and a well plate with a bottom surface and a top surface, wherein the bottom surface of the well plate is mounted on the top surface of the compressible membrane layer, and wherein the well plate contains one or more liquid wells and one or more sealed liquid compartments substantially in alignment with the piercer features of the top substrate.
In certain embodiments, the DMF component may include a bottom substrate and a top substrate, each having a bottom surface and a top surface, wherein the top substrate contains one or more openings through which a liquid can flow. The DMF component may include one or more pairs of piercer features extending upwards from the top surface of the top substrate, wherein each pair of piercer features are separated by a gap, thereby forming a flow channel therethrough, and wherein the flow channels are in substantial alignment with the openings. A droplet operations gap may be interposed between the top surface of the bottom substrate and the bottom surface of the top substrate, thereby separating the bottom substrate and the top substrate to form a chamber in which droplet operations can be performed, wherein the flow channels are in liquid contact with the droplet operations gap via the openings. The cartridge may include a first compressible membrane layer with a top surface and a bottom surface, wherein the bottom surface of the first compressible membrane later is mounted on top of the top surface of the top substrate. The invention may include a well plate component including: a second compressible membrane layer having a top surface and a bottom surface; and a well plate with a bottom surface and a top surface, wherein the bottom surface of the well plate is mounted on the top surface of the second compressible membrane layer. The DMF and well plate components may be mated to form a single operational cartridge. In some cases, the means for applying a compression force applies the compression force either to the well plate portion only, to the DMF portion only, or to the well plate portion and the DMF portion in opposition at substantially the same time. In some cases, the piercer features are arranged such that, upon actuation of the means for applying a compression force, application of the compression force causes the piercer features to pass upwards through the first and second compressible membrane layers and into the liquid wells, thereby allowing liquid to flow through the flow channels into the droplet operations gap via the openings, and simultaneously causes the piercer features to penetrate the seals of the sealed liquid compartments, thereby allowing liquid to flow through the flow channels into the droplet operations gap via the openings, and wherein the liquid is sealed within the droplet operations gap when the first and second compressible membrane layers are returned to their uncompressed states.
The DMF component may include a bottom substrate and a top substrate, each having a bottom surface and a top surface, wherein the top substrate contains one or more openings through which a liquid can flow, whereon at least one of the openings is larger than the other openings; one or more pairs of piercer features extending upwards from the top surface of the top substrate, wherein each pair of piercer features are separated by a gap, thereby forming a flow channel therethrough, and wherein the flow channels are in substantial alignment with the openings, and wherein at least one pair of piercer features is larger than the other piercer features; a droplet operations gap interposed between the top surface of the bottom substrate and the bottom surface of the top substrate, thereby separating the bottom substrate and the top substrate to form a chamber in which droplet operations can be performed, wherein the flow channels are in liquid contact with the droplet operations gap via the openings; and a first compressible membrane layer including a thick portion and a thin portion, each portion having a top surface and a bottom surface, and wherein the bottom surfaces of the thin portion and the thick portion are mounted on the top surface of the top substrate, a first compressible membrane layer including a thick portion and a thin portion, each portion having a top surface and a bottom surface, and wherein the bottom surfaces of the thin portion and the thick portion are mounted on the top surface of the top substrate, wherein the thick portion is substantially aligned with the larger piercer feature and the thin portion is substantially aligned with the other piercer features. The cartridge may include a well plate component including: a well plate with a bottom surface and a top surface, wherein the well plate may include liquid wells in liquid contact with the top surface of the second compressible membrane layer, wherein one of the liquid wells is substantially aligned with the larger piercer feature and may include a larger size, surface area, and volume that other liquid wells; and a second compressible membrane layer having a top surface and a bottom surface, wherein the top surface of the second compressible membrane layer is mounted on the bottom surface of the well plate. The DMF and well plate components may be mated to form a single operational cartridge.
The disclosure provides a digital microfluidics cartridge, which may include a bottom substrate and a top substrate, each having a bottom surface and a top surface, wherein the top substrate may include one or more liquid loading ports contained therein; and a droplet operations gap interposed between the top surface of the bottom substrate and the bottom surface of the top substrate, thereby separating the bottom substrate and the top substrate to form a chamber in which droplet operations can be performed, wherein the liquid loading ports are in liquid contact with the droplet operations gap; and a compressible membrane layer having a top surface and a bottom surface and including one or more hollow needle features each including an opening at the distal end of the hollow needle feature, wherein the hollow needle features protrude downward from the well plate portion and towards the DMF portion and wherein the openings are sealed while the compressible membrane layer is in an uncompressed state; and a well plate with a bottom surface and a top surface, wherein the well plate may include liquid wells in liquid contact with the hollow needle features, wherein the bottom surface of the well plate is in contact with the top surface of the compressible membrane layer and wherein the liquid wells are in substantial alignment with the hollow needle features and the liquid loading ports. Applying a compression force causes the hollow needle feature to pass through the compressible membrane layer and into the droplet operations gap, thereby permitting liquid to flow from the liquid wells into the droplet operations gap via the liquid loading ports, and wherein liquid is sealed within the droplet operations gap when the compressible membrane layer is returned to its uncompressed state.
The cartridge may include a DMF component including: a bottom substrate and a top substrate, each having a bottom surface and a top surface, wherein the top substrate may include one or more liquid loading ports contained therein; a droplet operations gap interposed between the top surface of the bottom substrate and the bottom surface of the top substrate, thereby separating the bottom substrate and the top substrate to form a chamber in which droplet operations can be performed, wherein the liquid loading ports are in liquid contact with the droplet operations gap; and a first compressible membrane layer with a top surface and a bottom surface, wherein the bottom surface of the first compressible membrane later is mounted on top of the top surface of the top substrate.
The cartridge may include a well plate component including: a second compressible membrane layer having a top surface and a bottom surface and including one or more hollow needle features each including an opening at the distal end of the hollow needle feature, wherein the hollow needle features protrude downward from the top surface of well plate component and wherein the openings are sealed while the second compressible membrane layer is in an uncompressed state; and a well plate with a bottom surface and a top surface, wherein the well plate may include an array of liquid wells in liquid contact with the hollow needle features, wherein the bottom surface of the well plate is in contact with the top surface of the second compressible membrane layer and wherein the liquid wells are in substantial alignment with the hollow needle features; wherein the DMF and well plate components are mated to form a single operational cartridge.
In various embodiments, the means for applying a compression force applies the compression force either to the well plate portion only, to the DMF portion only, or to the well plate portion and the DMF portion in opposition at substantially the same time.
In some cases, the sealed liquid compartments comprise pre-filled blister packs.
In some cases, liquid can be externally introduced into the liquid wells via a pipette.
In some cases, the liquid wells are pre-loaded with liquids, wherein the liquid is sealed within the liquid wells by a sealing membrane.
In some cases, one or more of the wells is pre-loaded with a liquid. The liquid may be sealed within the well by a sealing membrane. The liquid may, for example, be selected from a group consisting of sample liquids, reagents, buffer solutions, or low-viscosity oils.
The means for applying a compression force may include a pressure plate or membrane. The liquid may include a low-viscosity oil selected from a group consisting of a silicone oil or a hexadecane filler liquid.
In some cases, the droplet operations gap is pre-loaded with a low-viscosity oil.
The cartridge may include an adhesive bonding a bottom surface of the compressible membrane layer to a top surface of the top substrate and a top surface of the compressible membrane layer to a bottom surface of the well plate.
In some cases, the compressible membrane layer is from about 1 mm to about 25 mm thick when uncompressed and from about 0.7 mm to about 19 mm thick when compressed. In some cases, the hollow needle is from about 0.9 mm to about 20 mm in length. In some cases, the compressible membrane layer is composed of a rubber or elastomer compound.
In certain embodiments, the rubber or elastomer compound is selected from a group consisting of a natural rubber compound, a silicone rubber compound, butyl rubber compounds, ethylene propylene diene monomer (EPDM) compounds, nitrile rubber compounds, polychloroprene rubber compounds, fluorocarbon rubber compounds, and tetrafluoroethylene/propylene (TPE/P) rubber compounds.
The cartridge may be configured such that a compression force applied to the compressible membrane layer seals the wells while the compressible membrane layer is in a compressed state, thereby preventing the flow of liquid out of the droplet operations gap while the hollow needle is liquidly connected to the droplet operations gap.
In all of the embodiments described herein, the means for applying a first compression force and a second a compression force may be provided on the cartridge and/or on the instrument.
In some cases, the means for applying the first compression force applies a first compression force to the thick portion of the first compressible membrane layer and the second compression force applies a second compression force to the thin portion of the first compression membrane layer.
In some cases, in a first actuation stage, the larger piercer feature is arranged such that, upon actuation of the means for applying a first compression force and a second compression force, application of the first compression force causes the larger piercer feature to pass upwards through the thick portion of the first compressible membrane layer and the second compressible membrane layer and into the larger liquid well, thereby allowing liquid to flow through the flow channel into the droplet operations gap via the opening, and wherein in a second actuation stage, the other piercer features are arranged such that, upon actuation of the means for applying a first compression force and a second compression force, application of the second compression force causes the other piercer features to pass upwards through the thin portion of the first compression membrane layer and the second compression membrane layer and into other liquid wells, thereby allowing liquid to flow through the flow channels into the droplet operations gap via the openings. Liquid may be sealed within the droplet operations gap when the DMF component and the well plate component of the single operational cartridge are separated.
The disclosure provides a method for filling a cartridge as described herein, e.g., by providing the cartridge; supplying the liquid wells with liquid to be processed; actuating a first liquid dispensing operation by applying the first compression force; actuating a second liquid dispensing operation by applying the second compression force; and suspending liquid dispensing operations by removing compression forces from the two-component cartridge.
The features and advantages of the present invention will be more clearly understood from the following description taken in conjunction with the accompanying drawings, which are not necessarily drawn to scale.
“Activate,” with reference to one or more electrodes, means affecting a change in the electrical state of the one or more electrodes which, in the presence of a droplet, results in a droplet operation. Activation of an electrode can be accomplished using alternating current (AC) or direct current (DC). Any suitable voltage may be used. For example, an electrode may be activated using a voltage which is greater than about 5 V, or greater than about 20 V, or greater than about 40 V, or greater than about 100 V, or greater than about 200 V or greater than about 300 V. The suitable voltage being a function of the dielectric's properties such as thickness and dielectric constant, liquid properties such as viscosity and many other factors as well. Where an AC signal is used, any suitable frequency may be employed. For example, an electrode may be activated using an AC signal having a frequency from about 1 Hz to about 10 MHz, or from about 1 Hz and 10 KHz, or from about 10 Hz to about 240 Hz, or about 60 Hz.
“Droplet” means a volume of liquid on a droplet actuator. Typically, a droplet is at least partially bounded by a filler liquid. For example, a droplet may be surrounded by a filler liquid or may be bounded by filler liquid and one or more surfaces of the droplet actuator. As another example, a droplet may be bounded by filler liquid, one or more surfaces of the droplet actuator, and/or the atmosphere. In yet another example, a droplet may be bounded by filler liquid and the atmosphere. Droplets may, for example, be aqueous or non-aqueous or may be mixtures or emulsions including aqueous and non-aqueous components. Droplets may take a wide variety of shapes; non-limiting examples include generally disc shaped, slug shaped, truncated sphere, ellipsoid, spherical, partially compressed sphere, hemispherical, ovoid, cylindrical, combinations of such shapes, and various shapes formed during droplet operations, such as merging or splitting or formed as a result of contact of such shapes with one or more surfaces of a droplet actuator. For examples of droplet liquids that may be subjected to droplet operations using the approach of the invention, see International Patent Application No. PCT/US 06/47486, entitled, “Droplet-Based Biochemistry,” filed on Dec. 11, 2006.
In various embodiments, a droplet may include a biological sample, such as whole blood, lymphatic liquid, serum, plasma, sweat, tear, saliva, sputum, cerebrospinal liquid, amniotic liquid, seminal liquid, vaginal excretion, serous liquid, synovial liquid, pericardial liquid, peritoneal liquid, pleural liquid, transudates, exudates, cystic liquid, bile, urine, gastric liquid, intestinal liquid, fecal samples, liquids containing single or multiple cells, liquids containing organelles, liquidized tissues, liquidized organisms, liquids containing multi-celled organisms, biological swabs and biological washes. Moreover, a droplet may include a reagent, such as water, deionized water, saline solutions, acidic solutions, basic solutions, detergent solutions and/or buffers.
Other examples of droplet contents include reagents, such as a reagent for a biochemical protocol, such as a nucleic acid amplification protocol, an affinity-based assay protocol, an enzymatic assay protocol, a sequencing protocol, and/or a protocol for analyses of biological liquids. A droplet may include one or more beads.
“Droplet Actuator” means a device for manipulating droplets. For examples of droplet actuators, see Pamula et al., U.S. Pat. No. 6,911,132, entitled “Apparatus for Manipulating Droplets by Electrowetting-Based Techniques,” issued on Jun. 28, 2005; Pamula et al., U.S. patent application Ser. No. 11/343,284, entitled “Apparatuses and Methods for Manipulating Droplets on a Printed Circuit Board,” filed on filed on Jan. 30, 2006; Pollack et al., International Patent Application No. PCT/US2006/047486, entitled “Droplet-Based Biochemistry,” filed on Dec. 11, 2006; Shenderov, U.S. Pat. No. 6,773,566, entitled “Electrostatic Actuators for Microfluidics and Methods for Using Same,” issued on Aug. 10, 2004 and U.S. Pat. No. 6,565,727, entitled “Actuators for Microfluidics Without Moving Parts,” issued on Jan. 24, 2000; Kim and/or Shah et al., U.S. patent application Ser. No. 10/343,261, entitled “Electrowetting-driven Micropumping,” filed on Jan. 27, 2003, Ser. No. 11/275,668, entitled “Method and Apparatus for Promoting the Complete Transfer of Liquid Drops from a Nozzle,” filed on Jan. 23, 2006, Ser. No. 11/460,188, entitled “Small Object Moving on Printed Circuit Board,” filed on Jan. 23, 2006, Ser. No. 12/465,935, entitled “Method for Using Magnetic Particles in Droplet Microfluidics,” filed on May 14, 2009, and Ser. No. 12/513,157, entitled “Method and Apparatus for Real-time Feedback Control of Electrical Manipulation of Droplets on Chip,” filed on Apr. 30, 2009; Velev, U.S. Pat. No. 7,547,380, entitled “Droplet Transportation Devices and Methods Having a Liquid Surface,” issued on Jun. 16, 2009; Sterling et al., U.S. Pat. No. 7,163,612, entitled “Method, Apparatus and Article for Microfluidic Control via Electrowetting, for Chemical, Biochemical and Biological Assays and the Like,” issued on Jan. 16, 2007; Becker and Gascoyne et al., U.S. Pat. No. 7,641,779, entitled “Method and Apparatus for Programmable fluidic Processing,” issued on Jan. 5, 2010, and U.S. Pat. No. 6,977,033, entitled “Method and Apparatus for Programmable fluidic Processing,” issued on Dec. 20, 2005; Decre et al., U.S. Pat. No. 7,328,979, entitled “System for Manipulation of a Body of Liquid,” issued on Feb. 12, 2008; Yamakawa et al., U.S. Patent Pub. No. 20060039823, entitled “Chemical Analysis Apparatus,” published on Feb. 23, 2006; Wu, International Patent Pub. No. WO/2009/003184, entitled “Digital Microfluidics Based Apparatus for Heat-exchanging Chemical Processes,” published on Dec. 31, 2008; Fouillet et al., U.S. Patent Pub. No. 20090192044, entitled “Electrode Addressing Method,” published on Jul. 30, 2009; Fouillet et al., U.S. Pat. No. 7,052,244, entitled “Device for Displacement of Small Liquid Volumes Along a Micro-catenary Line by Electrostatic Forces,” issued on May 30, 2006; Marchand et al., U.S. Patent Pub. No. 20080124252, entitled “Droplet Microreactor,” published on May 29, 2008; Adachi et al., U.S. Patent Pub. No. 20090321262, entitled “Liquid Transfer Device,” published on Dec. 31, 2009; Roux et al., U.S. Patent Pub. No. 20050179746, entitled “Device for Controlling the Displacement of a Drop Between two or Several Solid Substrates,” published on Aug. 18, 2005; Dhindsa et al., “Virtual Electrowetting Channels: Electronic Liquid Transport with Continuous Channel Functionality,” Lab Chip, 10:832-836 (2010); the entire disclosures of which are incorporated herein by reference, along with their priority documents.
Certain droplet actuators will include one or more substrates arranged with a droplet operations gap therebetween and electrodes associated with (e.g., layered on, attached to, and/or embedded in) the one or more substrates and arranged to conduct one or more droplet operations. For example, certain droplet actuators will include a base (or bottom) substrate, droplet operations electrodes associated with the substrate, one or more dielectric layers atop the substrate and/or electrodes, and optionally one or more hydrophobic layers atop the substrate, dielectric layers and/or the electrodes forming a droplet operations surface.
A top substrate may also be provided, which is separated from the droplet operations surface by a gap, commonly referred to as a droplet operations gap. Various electrode arrangements on the top and/or bottom substrates are discussed in the above-referenced patents and applications and certain novel electrode arrangements are discussed in the description of the invention.
During droplet operations it is preferred that droplets remain in continuous contact or frequent contact with a ground or reference electrode.
A ground or reference electrode may be associated with the top substrate facing the gap, the bottom substrate facing the gap, in the gap. Where electrodes are provided on both substrates, electrical contacts for coupling the electrodes to a droplet actuator instrument for controlling or monitoring the electrodes may be associated with one or both plates.
In some cases, electrodes on one substrate are electrically coupled to the other substrate so that only one substrate is in contact with the droplet actuator. In one embodiment, a conductive material (e.g., an epoxy, such as MASTER BOND™ Polymer System EP79, available from Master Bond, Inc., Hackensack, NJ) provides the electrical connection between electrodes on one substrate and electrical paths on the other substrates, e.g., a ground electrode on a top substrate may be coupled to an electrical path on a bottom substrate by such a conductive material.
Where multiple substrates are used, a spacer may be provided between the substrates to determine the height of the gap therebetween and define on-actuator dispensing reservoirs. The spacer height may, for example, be from about 5 μm to about 1000 μm, or about 100 μm to about 400 μm, or about 200 μm to about 350 μm, or about 250 μm to about 300 μm, or about 275 μm. The spacer may, for example, be formed of a layer of projections form the top or bottom substrates, and/or a material inserted between the top and bottom substrates.
One or more openings may be provided in the one or more substrates for forming a liquid path through which liquid may be delivered into the droplet operations gap. The one or more openings may in some cases be aligned for interaction with one or more electrodes, e.g., aligned such that liquid flowed through the opening will come into sufficient proximity with one or more droplet operations electrodes to permit a droplet operation to be affected by the droplet operations electrodes using the liquid.
The base (or bottom) and top substrates may in some cases be formed as one integral component.
One or more reference electrodes may be provided on the base (or bottom) and/or top substrates and/or in the gap. Examples of reference electrode arrangements are provided in the above referenced patents and patent applications.
In various embodiments, the manipulation of droplets by a droplet actuator may be electrode mediated, e.g., electrowetting mediated or dielectrophoresis mediated or Coulombic force mediated. Examples of other techniques for controlling droplet operations that may be used in the droplet actuators of the invention include using devices that induce hydrodynamic fluidic pressure, such as those that operate on the basis of mechanical principles (e.g. external syringe pumps, pneumatic membrane pumps, vibrating membrane pumps, vacuum devices, centrifugal forces, piezoelectric/ultrasonic pumps and acoustic forces); electrical or magnetic principles (e.g. electroosmotic flow, electrokinetic pumps, ferrofluidic plugs, electrohydrodynamic pumps, attraction or repulsion using magnetic forces and magnetohydrodynamic pumps); thermodynamic principles (e.g. gas bubble generation/phase-change-induced volume expansion); other kinds of surface-wetting principles (e.g. electrowetting, and optoelectrowetting, as well as chemically, thermally, structurally and radioactively induced surface-tension gradients); gravity; surface tension (e.g., capillary action); electrostatic forces (e.g., electroosmotic flow); centrifugal flow (substrate disposed on a compact disc and rotated); magnetic forces (e.g., oscillating ions causes flow); magnetohydrodynamic forces; and vacuum or pressure differential.
In certain embodiments, combinations of two or more of the foregoing techniques may be employed to conduct a droplet operation in a droplet actuator of the invention. Similarly, one or more of the foregoing may be used to deliver liquid into a droplet operations gap, e.g., from a reservoir in another device or from an external reservoir of the droplet actuator (e.g., a reservoir associated with a droplet actuator substrate and a flow path from the reservoir into the droplet operations gap).
Droplet operations surfaces of certain droplet actuators of the invention may be made from hydrophobic materials or may be coated or treated to make them hydrophobic. For example, in some cases some portion or all the droplet operations surfaces may be derivatized with low surface-energy materials or chemistries, e.g., by deposition or using in situ synthesis using compounds such as poly- or per-fluorinated compounds in solution or polymerizable monomers. Examples include TEFLON® AF (available from DuPont, Wilmington, DE), members of the cytop family of materials, coatings in the FLUOROPEL® family of hydrophobic and superhydrophobic coatings (available from Cytonix Corporation, Beltsville, MD), silane coatings, fluorosilane coatings, hydrophobic phosphonate derivatives (e.g., those sold by Aculon, Inc), and NOVEC™ electronic coatings (available from 3M Company, St. Paul, MN), other fluorinated monomers for plasma-enhanced chemical vapor deposition (PECVD), and organosiloxane (e.g., SiOC) for PECVD.
In some cases, the droplet operations surface may include a hydrophobic coating having a thickness ranging from about 10 nm to about 1,000 nm.
Moreover, in some embodiments, the top substrate of the droplet actuator includes an electrically conducting organic polymer, which is then coated with a hydrophobic coating or otherwise treated to make the droplet operations surface hydrophobic. For example, the electrically conducting organic polymer that is deposited onto a plastic substrate may be poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS).
Other examples of electrically conducting organic polymers and alternative conductive layers are described in Pollack et al., International Patent Application No. PCT/US2010/040705, entitled “Droplet Actuator Devices and Methods,” the entire disclosure of which is incorporated herein by reference. One or both substrates may be fabricated using a printed circuit board (PCB), glass, indium tin oxide (ITO)-coated glass, and/or semiconductor materials as the substrate. When the substrate is ITO-coated glass, the ITO coating is preferably a thickness in the range of about 20 to about 200 nm, preferably about 50 to about 150 nm, or about 75 to about 125 nm, or about 100 nm.
In some cases, the top and/or bottom substrate includes a PCB substrate that is coated with a dielectric, such as a polyimide dielectric, which may in some cases also be coated or otherwise treated to make the droplet operations surface hydrophobic. When the substrate includes a PCB, the following materials are examples of suitable materials: MITSUI™ BN-300 (available from MITSUI Chemicals America, Inc., San Jose CA); ARLON™ 11N (available from Arlon, Inc, Santa Ana, CA).; NELCO® N4000-6 and N5000-30/32 (available from Park Electrochemical Corp., Melville, NY); ISOLA™ FR406 (available from Isola Group, Chandler, AZ), especially IS620; fluoropolymer family (suitable for fluorescence detection since it has low background fluorescence); polyimide family; polyester; polyethylene naphthalate; polycarbonate; polyetheretherketone; liquid crystal polymer; cyclo-olefin copolymer (COC); cyclo-olefin polymer (COP); aramid; THERMOUNT® nonwoven aramid reinforcement (available from DuPont, Wilmington, DE); NOMEX® brand fiber (available from DuPont, Wilmington, DE); and paper. Various materials are also suitable for use as the dielectric component of the substrate.
Examples include: vapor deposited dielectric, such as PARYLENE™ C, PARYLENE™ N, PARYLENE™ F and PARYLENE™ HT (for high temperature, −300° C.) (available from Parylene Coating Services, Inc., Katy, TX); TEFLON® AF coatings; cytop; soldermasks, such as liquid photoimageable soldermasks (e.g., on PCB) like TAIYO™ PSR4000 series, TAIYO™ PSR and AUS series (available from Taiyo America, Inc. Carson City, NV) (good thermal characteristics for applications involving thermal control), and PROBIMER™ 8165 (good thermal characteristics for applications involving thermal control (available from Huntsman Advanced Materials Americas Inc., Los Angeles, CA); dry film soldermask, such as those in the VACREL® dry film soldermask line (available from DuPont, Wilmington, DE); film dielectrics, such as polyimide film (e.g., KAPTON® polyimide film, available from DuPont, Wilmington, DE), polyethylene, and fluoropolymers (e.g., FEP), polytetrafluoroethylene; polyester; polyethylene naphthalate; cyclo-olefin copolymer (COC); cyclo-olefin polymer (COP); any other PCB substrate material listed above; black matrix resin; polypropylene; and black flexible circuit materials, such as DuPont™ Pyralux® HXC and DuPont™ Kapton® MBC (available from DuPont, Wilmington, DE).
Droplet transport voltage and frequency may be selected for performance with reagents used in specific assay protocols. Design parameters may be varied, e.g., number and placement of on-actuator reservoirs, number of independent electrode connections, size (volume) of different reservoirs, placement of magnets/bead washing zones, electrode size, electrode shape, inter-electrode spacing, and gap height (between top and bottom substrates) may be varied for use with specific reagents, protocols, droplet volumes, etc. In some cases, a substrate of the invention may be derivatized with low surface-energy materials or chemistries, e.g., using deposition or in situ synthesis using poly- or per-fluorinated compounds in solution or polymerizable monomers. Examples include TEFLON® AF coatings and FLUOROPEL® coatings for dip or spray coating, other fluorinated monomers for plasma-enhanced chemical vapor deposition (PECVD), and organosiloxane (e.g., SiOC) for PECVD.
Additionally, in some cases, some portion or all the droplet operations surface may be coated with a substance for reducing background noise, such as background fluorescence from a PCB substrate. For example, the noise-reducing coating may include a black matrix resin, such as the black matrix resins available from Toray industries, Inc., Japan.
Electrodes of a droplet actuator are typically controlled by a controller or a processor, which is itself provided as part of a system, which may include processing functions as well as data and software storage and input and output capabilities.
Reagents may be provided on the droplet actuator in the droplet operations gap or in a reservoir liquidly coupled to the droplet operations gap. The reagents may be in liquid form, e.g., droplets, or they may be provided in a reconstitutable form in the droplet operations gap or in a reservoir liquidly coupled to the droplet operations gap. Reconstitutable reagents may typically be combined with liquids for reconstitution. An example of reconstitutable reagents suitable for use with the invention includes those described in Meathrel, et al., U.S. Pat. No. 7,727,466, entitled “Disintegratable films for diagnostic devices,” granted on Jun. 1, 2010.
“Droplet operation” means any manipulation of a droplet on a droplet actuator. A droplet operation may, for example, include: loading a droplet into the droplet actuator; dispensing one or more droplets from a source droplet; splitting, separating or dividing a droplet into two or more droplets; transporting a droplet from one location to another in any direction; merging or combining two or more droplets into a single droplet; diluting a droplet; mixing a droplet; agitating a droplet; deforming a droplet; retaining a droplet in position; incubating a droplet; heating a droplet; vaporizing a droplet; cooling a droplet; disposing of a droplet; transporting a droplet out of a droplet actuator; other droplet operations described herein; and/or any combination of the foregoing. The terms “merge,” “merging,” “combine,” “combining” and the like are used to describe the creation of one droplet from two or more droplets.
When such a term is used in reference to two or more droplets, any combination of droplet operations that are sufficient to result in the combination of the two or more droplets into one droplet may be used. For example, “merging droplet A with droplet B,” can be achieved by transporting droplet A into contact with a stationary droplet B, transporting droplet B into contact with a stationary droplet A, or transporting droplets A and B into contact with each other.
The terms “splitting,” “separating” and “dividing” are not intended to imply any particular outcome with respect to volume of the resulting droplets (i.e., the volume of the resulting droplets can be the same or different) or number of resulting droplets (the number of resulting droplets may be 2, 3, 4, 5 or more).
The term “mixing” refers to droplet operations which result in more homogenous distribution of one or more components within a droplet. Examples of “loading” droplet operations include microdialysis loading, pressure assisted loading, robotic loading, passive loading, and pipette loading. Droplet operations may be electrode mediated.
In some cases, droplet operations are further facilitated using hydrophilic and/or hydrophobic regions on surfaces and/or by physical obstacles. For examples of droplet operations, see the patents and patent applications cited above under the definition of “droplet actuator.” Impedance and/or capacitance sensing and/or imaging techniques may sometimes be used to determine or confirm the outcome of a droplet operation. Examples of such techniques are described in Sturmer et al., International Patent Pub. No. WO/2008/101194, entitled “Capacitance Detection in a Droplet Actuator,” published on Aug. 21, 2008, the entire disclosure of which is incorporated herein by reference.
The sensing or imaging techniques may be used to confirm the presence or absence of a droplet at a specific electrode. For example, the presence of a dispensed droplet at the destination electrode following a droplet dispensing operation confirms that the droplet dispensing operation was effective. Similarly, the presence of a droplet at a detection spot at an appropriate step in an assay protocol may confirm that a previous set of droplet operations has successfully produced a droplet for detection.
Droplet transport time can be quite fast. For example, in various embodiments, transport of a droplet from one electrode to the next may be completed within about 1 sec, or about 0.1 sec, or about 0.01 sec, or about 0.001 sec. In one embodiment, the electrode is operated in AC mode but is switched to DC mode for imaging. It is helpful for conducting droplet operations for the footprint area of droplet to be like or larger than the electrowetting area; in other words, 1×-, 2×-3×-droplets are usefully controlled and/or operated using 1, 2, and 3 electrodes, respectively. If the droplet footprint is greater than number of electrodes available for conducting a droplet operation at a given time, then the difference between the droplet size and the number of electrodes should typically not be greater than 1; in other words, a 2× droplet is usefully controlled using 1 electrode and a 3× droplet is usefully controlled using 2 electrodes. When droplets include beads, it is useful for droplet size to be equal to the number of electrodes controlling the droplet, e.g., transporting the droplet.
“Filler liquid” means a liquid associated with a droplet operations substrate of a droplet actuator, which liquid is sufficiently immiscible with a droplet phase to render the droplet phase subject to electrode-mediated droplet operations. For example, the droplet operations gap of a droplet actuator is typically filled with a filler liquid. The filler liquid may, for example, be or include a low-viscosity oil, such as silicone oil or hexadecane filler liquid. The filler liquid may be or include a halogenated oil, such as a fluorinated or perfluorinated oil. The filler liquid may fill the entire gap of the droplet actuator or may coat one or more surfaces of the droplet actuator. Filler liquids may be selected to improve droplet operations and/or reduce loss of reagent or target substances from droplets, improve formation of microdroplets, reduce cross contamination between droplets, reduce contamination of droplet actuator surfaces, reduce degradation of droplet actuator materials, etc. For example, filler liquids may be selected for compatibility with droplet actuator materials.
As an example, fluorinated filler liquids may be usefully employed with fluorinated surface coatings. Fluorinated filler liquids are useful to reduce loss of lipophilic compounds, such as umbelliferone substrates like 6-hexadecanoylamido-4-methylumbelliferone substrates (e.g., for use in Krabbe, Niemann-Pick, or other assays); other umbelliferone substrates are described in U.S. Patent Pub. No. 20110118132, published on May 19, 2011, the entire disclosure of which is incorporated herein by reference. Examples of suitable fluorinated oils include those in the Galden line, such as Galden HT170 (bp=170° C., viscosity=1.8 cSt, density=1.77), Galden HT200 (bp=200C, viscosity=2.4 cSt, d=1.79), Galden HT230 (bp=230C, viscosity=4.4 cSt, d=1.82) (all from Solvay Solexis); those in the Novec line, such as Novec 7500 (bp=128C, viscosity=0.8 cSt, d=1.61), Fluorinert FC-40 (bp=155° C., viscosity=1.8 cSt, d=1.85), Fluorinert FC-43 (bp=174° C., viscosity=2.5 cSt, d=1.86) (both from 3M). In general, selection of perfluorinated filler liquids is based on kinematic viscosity (<7 cSt is preferred, but not required), and on boiling point (>150° C. is preferred, but not required, for use in DNA/RNA-based applications (PCR, etc.)). Filler liquids may, for example, be doped with surfactants or other additives.
For example, additives may be selected to improve droplet operations and/or reduce loss of reagent or target substances from droplets, formation of microdroplets, cross contamination between droplets, contamination of droplet actuator surfaces, degradation of droplet actuator materials, etc.
Composition of the filler liquid, including surfactant doping, may be selected for performance with reagents used in the specific assay protocols and effective interaction or non-interaction with droplet actuator materials. Examples of filler liquids and filler liquid formulations suitable for use with the invention are provided in Srinivasan et al, International Patent Pub. Nos. WO/2010/027894, entitled “Droplet Actuators, Modified Liquids and Methods,” published on Mar. 11, 2010, and WO/2009/021173, entitled “Use of Additives for Enhancing Droplet Operations,” published on Feb. 12, 2009; Sista et al., International Patent Pub. No. WO/2008/098236, entitled “Droplet Actuator Devices and Methods Employing Magnetic Beads,” published on Aug. 14, 2008; and Monroe et al., U.S. Patent Publication No. 20080283414, entitled “Electrowetting Devices,” filed on May 17, 2007; the entire disclosures of which are incorporated herein by reference, as well as the other patents and patent applications cited herein. Fluorinated oils may in some cases be doped with fluorinated surfactants, e.g., Zonyl FSO-100 (Sigma-Aldrich) and/or others.
“Reservoir” means an enclosure or partial enclosure configured for holding, storing, or supplying liquid. A droplet actuator system of the invention may include on-cartridge reservoirs and/or off-cartridge reservoirs. On-cartridge reservoirs may be (1) on-actuator reservoirs, which are reservoirs in the droplet operations gap or on the droplet operations surface; (2) off-actuator reservoirs, which are reservoirs on the droplet actuator cartridge, but outside the droplet operations gap, and not in contact with the droplet operations surface; or (3) hybrid reservoirs which have on-actuator regions and off-actuator regions.
An example of an off-actuator reservoir is a reservoir in the top substrate. An off-actuator reservoir is typically in liquid communication with an opening or flow path arranged for flowing liquid from the off-actuator reservoir into the droplet operations gap, such as into an on-actuator reservoir. An off-cartridge reservoir may be a reservoir that is not part of the droplet actuator cartridge at all, but which flows liquid to some portion of the droplet actuator cartridge. For example, an off-cartridge reservoir may be part of a system or docking station to which the droplet actuator cartridge is coupled during operation. Similarly, an off-cartridge reservoir may be a reagent storage container or syringe which is used to force liquid into an on-cartridge reservoir or into a droplet operations gap. A system using an off-cartridge reservoir will typically include a liquid passage means whereby liquid may be transferred from the off-cartridge reservoir into an on-cartridge reservoir or into a droplet operations gap.
“Washing” with respect to washing a surface, such as a hydrophilic surface, means reducing the amount and/or concentration of one or more substances in contact with the surface or exposed to the surface from a droplet in contact with the surface. The reduction in the amount and/or concentration of the substance may be partial, substantially complete, or even complete. The substance may be any of a wide variety of substances; examples include target substances for further analysis, and unwanted substances, such as components of a sample, contaminants, and/or excess reagent or buffer.
The terms “top,” “bottom,” “over,” “under,” and “on” are used throughout the description with reference to the relative positions of components of the droplet actuator, such as relative positions of top and bottom substrates of the droplet actuator. It will be appreciated that in many cases the droplet actuator is functional regardless of its orientation in space.
When a liquid in any form (e.g., a droplet or a continuous body, whether moving or stationary) is described as “on”, “at”, or “over” an electrode, array, matrix or surface, such liquid could be either in direct contact with the electrode/array/matrix/surface or could be in contact with one or more layers or films that are interposed between the liquid and the electrode/array/matrix/surface. In one example, filler liquid can be considered as a dynamic film between such liquid and the electrode/array/matrix/surface.
When a droplet is described as being “on” or “loaded on” a droplet actuator, it should be understood that the droplet is arranged on the droplet actuator in a manner which facilitates using the droplet actuator to conduct one or more droplet operations on the droplet, the droplet is arranged on the droplet actuator in a manner which facilitates sensing of a property of or a signal from the droplet, and/or the droplet has been subjected to a droplet operation on the droplet actuator.
The subject matter now will be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments of the subject matter are shown. Like numbers refer to like elements throughout. The subject matter may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Many modifications and other embodiments of the subject matter set forth herein will come to mind to one skilled in the art to which the subject matter pertains having the benefit of the teachings presented in the foregoing descriptions and the associated Drawings. Therefore, it is to be understood that the subject matter is not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims.
The disclosure provides a digital microfluidics (DMF) devices and methods for dispensing liquids using piercer features and compressible membranes.
The DMF device may include an arrangement of piercer features embedded in a compressible membrane layer that may be used as the actuation mechanism for dispensing liquids therein.
The DMF device may include a DMF portion and a well-plate portion and wherein the well-plate portion may include a needle feature embedded in a compressible membrane and positioned with respect to a liquid well and wherein the needle feature may be used to both pierce through the compressible membrane and to dispense liquid into the DMF portion.
The DMF device may include a DMF portion and a well-plate portion and wherein the well-plate portion may include a needle feature embedded in a compressible membrane and positioned with respect to a liquid well and a process of compressing together the well-plate portion and the DMF portion by which needle feature may pierce through the compressible membrane and dispense liquid into the DMF portion.
The DMF device may include a DMF portion and a well-plate portion and wherein the DMF portion includes piercer features embedded in a compressible membrane and positioned with respect to a liquid well in the well-plate portion and wherein the piercer features may be used to pierce through the compressible membrane and release liquid from the liquid well in the well-plate portion into the DMF portion.
The DMF device may include a DMF portion and a well-plate portion and wherein the DMF portion includes piercer features embedded in a compressible membrane and positioned with respect to a liquid well in the well-plate portion and a process of compressing together the well-plate portion and the DMF portion by which the piercer features may pierce through the compressible membrane and release liquid from the liquid well in the well-plate portion into the DMF portion.
The DMF device may include a DMF portion and a well-plate portion that are separatable and wherein membrane layers may be used to provide the connection/disconnection mechanism therebetween.
The DMF device may include a DMF portion and a well-plate portion that are separatable and wherein the DMF portion includes piercer features embedded in a compressible membrane and positioned with respect to at least two liquid wells in the well-plate portion for dispensing liquid into the DMF portion using a two-stage actuation process.
The DMF device may include DMF piercer features embedded in a compressible membrane and wherein the compressible membrane may be used for aspirating liquid instead of dispensing liquid.
Additionally, a membrane layer 120 may be provided atop top substrate 112 and a well plate 122 may be provided atop membrane layer 120. Adhesive on both sides of membrane layer 120 may be used to bond membrane layer 120 to top substrate 112 on one side and to well plate 122 on the other side. In another example, membrane layer 120 may be placed without bonding. In yet another example, membrane layer 120 may be molded in-place during the manufacturing of, for example, top substrate 112. Well plate 122 may include a liquid well (or reservoir) 124 that substantially aligns with loading port 118 in top substrate 112. Liquid well 124 may hold, for example, from about 1 uL to about 10 mL of liquid. Further, a hollow needle feature 126 may be provided at the outlet of liquid well 124. Further, there is an opening 128 at the distal tip of needle feature 126. The thickness of membrane layer 120 is set such that needle feature 126 of liquid well 124 is embedded fully in membrane layer 120 when membrane layer 120 is in an uncompressed or relaxed state. At the same time, the thickness of membrane layer 120 is set such that needle feature 126 of liquid well 124 may punch through membrane layer 120 when membrane layer 120 is in a compressed state. In one example, needle feature 126 may be from about 0.9 mm to about 20 mm long. In this example, membrane layer 120 may be from about 1 mm to about 25 mm thick when uncompressed and from about 0.7 mm to about 19 mm thick when compressed.
The characteristics of membrane layer 120 are such that it may provide an air and moisture-tight seal against opening 128 of needle feature 126 when membrane layer 120 is in the uncompressed or relaxed state. Membrane layer 120 may be formed, for example, of rubber or elastomer compounds, such as, but not limited to, natural rubber compounds, silicone rubber compounds, butyl rubber compounds, ethylene propylene diene monomer (EPDM) rubber compounds, nitrile rubber compounds, polychloroprene (e.g., Neoprene®) rubber compounds, fluorocarbon (e.g., Viton®) rubber compounds, tetrafluoroethylene/propylene (TPE/P) rubber compounds, and the like.
In DMF device 100, bottom substrate 110 and top substrate 112 with droplet operations gap 114 therebetween may form a DMF portion 150 of DMF device 100. Further, membrane layer 120 and well plate 122 may form a well-plate portion 152 of DMF device 100. Needle feature 126 protruding downward from liquid well 124 in well plate 122 is one example of a well-plate piercer feature. More specifically, needle feature 126 protrudes downward from well-plate portion 152 and toward DMF portion 150 of DMF device 100.
Further, in DMF device 100, DMF portion 150 is not limited to one loading port 118 only and well-plate portion 152 is not limited to one liquid well 124 only. DMF device 100 may include any number and/or arrangements of loading ports 118 and corresponding liquid wells 124.
Referring now to
Next,
As described herein, to apply compression forces 140 to any DMF device may mean, for example, that (1) DMF portion 150 may be held stationary while compression forces 140 may be applied to well-plate portion 152; (2) well-plate portion 152 may be held stationary while compression forces 140 may be applied to DMF portion 150; and/or (3) opposite compression forces 140 may be applied to both DMF portion 150 and well-plate portion 152 at substantially the same time. The purpose of applying compression forces 140 to any DMF device that is described herein may be to compress one or more membrane layers, such as membrane layer 120 shown in
Next,
Next, upon completion of the liquid dispensing operation,
Referring now again to
In another example,
In two-piece DMF device 200, DMF portion 150 and well-plate portion 152 may be formed separately and then mated together. For example, membrane layer 136 on DMF portion 150 and membrane layer 120 on well-plate portion 152 provide a connection/disconnection mechanism. A benefit of two-piece DMF device 200 is that DMF portion 150 and well-plate portion 152 may be stored separately (e.g., well-plate portion 152 holding liquid 132 may be refrigerated).
Next,
Referring now again to DMF device 100 shown in
Referring now to
At a step 310, a DMF device is provided that may include a DMF portion and a well-plate portion and wherein the well-plate portion may include a needle feature embedded in a compressible membrane. In one example, the DMF device 100 shown in
At a step 315, a liquid well of the well-plate portion of the DMF device is filled with the liquid to be processed. For example, in either DMF device 100 shown in
At a step 320, a liquid dispensing operation from the well-plate portion to the DMF portion is actuated by applying compression force to the DMF device. For example, a liquid dispensing operation is actuated by applying compression force to either DMF device 100 shown in
At a step 325, the liquid dispensing operation from the well-plate portion to the DMF portion is suspended by removing the compression force from the DMF device. For example, the liquid dispensing operation is suspended by removing the compression force from either DMF device 100 shown in
Referring now again to
However, different from DMF device 100, DMF device 400 is absent needle feature 126 at the outlet of liquid well 124. In this example, well plate 122 of DMF device 400 may include at least one liquid well 124 and at least one blister pack 142. Blister pack 142 may be, for example, an off-the-shelf blister pack for holding pre-made reagents. Generally, blister packs include a foil and/or cellophane seal that may be broken or pierced to release the liquid therein. In this example, the breakable seal (not shown) of blister pack 142 faces membrane layer 120.
Additionally, in this example, top substrate 112 may include two loading ports 118. One loading port 118 for receiving liquid from liquid well 124 of well plate 122 and another loading port 118 for receiving liquid from blister pack 142 of well plate 122. Further, DMF device 400 may include certain piercer features 144 extending from each of the loading ports 118 into membrane layer 120 and toward well plate 122. For example, piercer features 144a may be directed toward liquid well 124 and piercer features 144b may be directed toward blister pack 142.
When membrane layer 120 is in the relaxed or uncompressed state, piercer features 144a and 144b are substantially embedded within membrane layer 120. In this state, membrane layer 120 seals shut the liquid path that is present through piercer features 144a and 144b to loading ports 118 that supply droplet operations gap 114. By contrast, when membrane layer 120 is in the compressed state, piercer features 144a and 144b may punch through the compressed membrane layer 120 and open up liquid paths from liquid well 124 and blister pack 142 to loading ports 118. Further, piercer features 144b may be used to pierce or rupture blister pack 142.
In this example, the thickness of membrane layer 120 is set such that piercer features 144 of top substrate 112 may be embedded fully in membrane layer 120 when membrane layer 120 is in an uncompressed or relaxed state. At the same time, the thickness of membrane layer 120 is set such that piercer features 144 of top substrate 112 may punch through membrane layer 120 when membrane layer 120 is in a compressed state. In one example, piercer features 144 may be from about 0.9 mm to about 20 mm long. In this example, membrane layer 120 may be from about 1.1 mm to about 25 mm thick when uncompressed and from about 0.7 mm to about 19 mm thick when compressed.
Further, in DMF device 400, well-plate portion 152 is not limited to one liquid well 124 only and one blister pack 142 only. DMF device 400 may include any number and/or arrangements of liquid wells 124 and blister packs 142 and corresponding loading ports 118. In one example, DMF device 400 may be provided preloaded with liquid 132. In another example, at runtime a pipette 130 may be used to fill liquid well 124 with some volume of liquid 132.
Referring now to
Next,
Next, upon completion of the liquid dispensing operation,
In another example,
In two-piece DMF device 500, DMF portion 150 and well-plate portion 152 may be formed separately and then mated together. For example, membrane layer 120 on DMF portion 150 and membrane layer 136 on well-plate portion 152 provide a connection/disconnection mechanism. A benefit of two-piece DMF device 500 is that DMF portion 150 and well-plate portion 152 may be stored separately (e.g., well-plate portion 152 holding liquid 132 may be refrigerated).
Referring now again to DMF device 400 shown in
Referring now to
At a step 610, a DMF device is provided that may include a DMF portion and a well-plate portion and wherein the DMF portion may include piercer features embedded in a compressible membrane. In one example, the DMF device 400 shown in
At a step 615, the well-plate portion of the DMF device is supplied with liquid to be processed. For example, in either DMF device 400 shown in
At a step 620, a liquid dispensing operation from the well-plate portion to the DMF portion is actuated by applying compression force to the DMF device. For example, a liquid dispensing operation is actuated by applying compression force to either DMF device 400 shown in
At a step 625, the liquid dispensing operation from the well-plate portion to the DMF portion is suspended by removing the compression force from the DMF device. For example, the liquid dispensing operation is suspended by removing the compression force from either DMF device 400 shown in
Referring now again to
Referring now to
In one example, piercer features 144a may be from about 0.9 mm to about 6 mm long or high. Accordingly, thin portion 123 of membrane layer 120 may be from about 1.1 mm to about 6.5 mm thick when uncompressed and from about 0.7 mm to about 5.5 mm thick when compressed. Further, in this example, piercer features 144b may be from about 4 mm to about 20 mm long or high. Accordingly, thick portion 121 of membrane layer 120 may be from about 4.5 mm to about 25 mm thick when uncompressed and from about 3.5 mm to about 18 mm thick when compressed.
Next, in a first actuation step,
Next, in a second actuation step,
Next, upon completion of the two-stage liquid dispensing operation,
Referring now to
At a step 810, a DMF device is provided that may include a DMF portion and a well-plate portion and wherein the DMF portion may include piercer features of differing lengths or heights embedded in a compressible membrane. In one example, the two-piece DMF device 700 shown in
At a step 815, the well-plate portion of the DMF device is supplied with liquid to be processed. For example, in two-piece DMF device 700 shown in
At a step 820, a first liquid dispensing operation from the well-plate portion to the DMF portion is actuated by applying a first amount of compression force to the DMF device. For example, the first liquid dispensing operation is actuated by applying a first amount of compression force to two-piece DMF device 700, as shown, for example, in
At a step 825, a second liquid dispensing operation from the well-plate portion to the DMF portion is actuated by applying additional compression force to the DMF device. For example, the second liquid dispensing operation is actuated by applying an additional amount of compression forces 140 to two-piece DMF device 700, as shown, for example, in
At a step 830, the liquid dispensing operation from the well-plate portion to the DMF portion is suspended by removing the compression force from the DMF device. For example, the liquid dispensing operation is suspended by removing the compression force from two-piece DMF device 700, as shown, for example, in
Referring now again to
Referring now again to
Referring now again to
Referring now to
Referring now to
In this example, a needle feature 126 may be configured as the inlet to a liquid port 118 with its opening 128 directed toward a liquid source in well-plate portion 152. For example, needle feature 126a may provide the inlet to liquid port 118a that may be supplied by liquid well 124 of well plate 122. Further, needle feature 126b may provide the inlet to liquid port 118b that may be supplied by blister pack 142. Further, needle features 126 may be embedded and sealed within membrane layer 120 when membrane layer 120 is in the uncompressed state. Additionally, in this example, instead of membrane layer 136 covering liquid well 124 and blister pack 142 of well plate 122, a frangible membrane 910 may be provided at well plate 122.
Frangible membrane 910 may be, for example, a foil and/or cellophane layer for sealing liquid well 124 and blister pack 142. However, at runtime frangible membrane 910 may be ruptured using needle features 126 so that liquid 132 may be released from liquid well 124 and blister pack 142 of well-plate portion 152 into DMF portion 150, as shown, for example, in
Further,
Referring now to
For example,
Further, balloon device 160 may be provided alongside and a short distance away from liquid well 124 of well plate 122. Balloon device 160 may include, for example, a needle feature 162 that has an opening 164 at the distal tip thereof, and a balloon 166 atop and supplying needle feature 162. In this example, needle feature 162 of balloon device 160 may pass through membrane layer 138 and well-plate 122 and is embedded in membrane layer 120 when membrane layer 120 is in the uncompressed state, like needle feature 126 of liquid well 124. In one example, needle feature 162 of balloon device 160 may be slightly longer (e.g., about 1 mm longer) than needle feature 126. Further, an air channel 168 may be provided in well-plate 122. For example, air channel 168 runs between the upper edge of liquid well 124 and the upper end of needle feature 162 of balloon device 160. Air channel 168 allows, for example, air to pass between liquid well 124 and balloon 166 of balloon device 160. Further, needle feature 162 of balloon device 160 substantially aligns with vent port 170 in top substrate 112 of DMF portion 150. Accordingly, when DMF portion 150 and well-plate portion 152 of two-piece DMF device 1000 are compressed together, then opening 164 of needle feature 162 may enter vent port 170.
Referring still to
Again, well-plate portion 152 of two-piece DMF device 1000 may be sealed using membrane layer 138 and is airtight. In a workflow using two-piece DMF device 1000, the filler liquid 116 may be pre-filled. A main difference between, for example, two-piece DMF device 200 shown in
Referring still to
Next,
Next,
Because all sides of two-piece DMF device 1000 are substantially airtight, it is important that balloon device 160 be present to relieve the air pressure. This is because the volume of liquid 132 pushed into DMF portion 150 must displace some air. This displaced air fills balloon 166. Further, because needle feature 162 of balloon device 160 may be slightly longer than needle feature 126, the air-pressure may be relieved via vent port 170 slightly before liquid 132 is introduced into loading port 118. Further,
Next, upon completion of the liquid dispensing operation,
Further, because DMF portion 150 and well-plate portion 152 of two-piece DMF device 1000 are fully sealed, the disposal of two-piece DMF device 1000 may be simplified. Further, it ensures that the instrument and instrument environment are un-contaminated.
Referring still to
In another example, balloon 166 at well-plate portion 152 is not connected to a needle. Instead, the needle may be provided at vent port 170 in DMF portion 150, as shown, for example, in two-piece DMF device 1000 of
Referring now to
For example,
Next,
Next,
Next,
Referring now again to
Referring now again to
Following long-standing patent law convention, the terms “a,” “an,” and “the” refer to “one or more” when used in this application, including the claims. Thus, for example, reference to “a subject” includes a plurality of subjects, unless the context clearly is to the contrary (e.g., a plurality of subjects), and so forth.
Throughout this specification and the claims, the terms “comprise,” “comprises,” “comprising,” “include,” “includes,” and “including,” are intended to be non-limiting, such that recitation of items in a list is not to the exclusion of other like items that may be substituted or added to the listed items.
Terms like “preferably,” “commonly,” and “typically” are not utilized herein to limit the scope of the claimed embodiments or to imply that certain features are critical or essential to the structure or function of the claimed embodiments. These terms are intended to highlight alternative or additional features that may or may not be utilized in a particular embodiment of the present disclosure.
The term “substantially” is utilized herein to represent the inherent degree of uncertainty that may be attributed to any quantitative comparison, value, measurement, or other representation and to represent the degree by which a quantitative representation may vary from a stated reference without resulting in a change in the basic function of the subject matter at issue.
Various modifications and variations of the disclosed methods, compositions and uses of the invention will be apparent to the skilled person without departing from the scope and spirit of the invention. Although the invention has been disclosed in connection with specific preferred aspects or embodiments, the invention as claimed should not be unduly limited to such specific aspects or embodiments.
For the purposes of this specification and appended claims, unless otherwise indicated, all numbers expressing amounts, sizes, dimensions, proportions, shapes, formulations, parameters, percentages, quantities, characteristics, and other numerical values used in the specification and claims, are to be understood as being modified in all instances by the term “about” even though the term “about” may not expressly appear with the value, amount, or range. Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are not and need not be exact but may be approximate and/or larger or smaller as desired, reflecting tolerances, conversion factors, rounding off, measurement error and the like, and other factors known to those of skill in the art depending on the desired properties sought to be obtained by the subject matter. For example, the term “about,” when referring to a value can be meant to encompass variations of, in some embodiments ±100%, in some embodiments ±50%, in some embodiments ±20%, in some embodiments ±10%, in some embodiments ±5%, in some embodiments ±1%, in some embodiments ±0.5%, and in some embodiments ±0.1% from the specified amount, as such variations are appropriate to perform the disclosed methods or employ the disclosed compositions.
Further, the term “about” when used in connection with one or more numbers or numerical ranges, should be understood to refer to all such numbers, including all numbers in a range and modifies that range by extending the boundaries above and below the numerical values set forth. The recitation of numerical ranges by endpoints includes all numbers, e.g., whole integers, including fractions thereof, subsumed within that range (for example, the recitation of 1 to 5 includes 1, 2, 3, 4, and 5, as well as fractions thereof, e.g., 1.5, 2.25, 3.75, 4.1, and the like) and any range within that range.
This application claims priority to U.S. Patent App. No. 63/144,947 filed on Feb. 2, 2021.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/CA2022/050146 | 2/1/2022 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 63144947 | Feb 2021 | US |
