METHOD AND APPARATUS FOR THE DISCRETIZATION AND MANIPULATION OF SAMPLE VOLUMES

• US 20100041046A1
• Filed: 07/27/2009
• Published: 02/18/2010
• Est. Priority Date: 08/15/2008
• Status: Active Grant

• Current Assignee: University of Washington
• Original Assignee: University of Washington
• Inventors: Cohen, Dawn W., Jeffries, Gavin D.M., Chiu, Daniel T.
• Granted Patent: US 9,180,453 B2
• Time in Patent Office: Days
• US Class Current: 435/6
• CPC Class Codes: B01L 2200/0642 Filling fluids into wells by specific techniques
• CPC Class Codes: B01L 2200/0673 Handling of plugs of fluid surrounded by immiscible fluid
• CPC Class Codes: B01L 2300/0877 Flow chambers
• CPC Class Codes: B01L 2300/0883 Serpentine channels
• CPC Class Codes: B01L 2300/165 Specific details about hydrophobic, oleophobic surfaces
• CPC Class Codes: B01L 2300/1827 using resistive heater
• CPC Class Codes: B01L 2300/1861 using radiation
• CPC Class Codes: B01L 2400/0439 ultrasonic vibrations, vibrating piezo elements
• CPC Class Codes: B01L 2400/0633 with moving parts
• CPC Class Codes: B01L 3/502 with fluid transport, e.g. in multi-compartment structures centrifugal-type cuvettes G01N21/07; analysis by separation into components G01N30/00; automatic analysers G01N35/00
• CPC Class Codes: B01L 3/502784 specially adapted for droplet or plug flow, e.g. digital microfluidics automatic analysis using a stream of discrete samples in a tube system G01N35/08
• CPC Class Codes: B01L 7/52 with provision for submitting samples to a predetermined sequence of different temperatures, e.g. for treating nucleic acid samples amplification or hybridisation processes per se C12Q1/68; controlling sequential reactions for synthesis B01J19/0046
• CPC Class Codes: G01N 2035/00356 Holding samples at elevated temperature (incubation)
• CPC Class Codes: G01N 2035/1032 Dilution or aliquotting
• CPC Class Codes: G01N 2035/1034 Transferring microquantities of liquid
• CPC Class Codes: G01N 35/08 using a stream of discrete samples flowing along a tube system, e.g. flow injection analysis
• CPC Class Codes: G01N 35/10 Devices for transferring samples or any liquids to, in, or from, the analysis apparatus, e.g. suction devices, injection devices G01N35/0099 takes precedence

Abstract

Embodiments of the present invention relate to methods and apparatuses for the discretization and manipulation of sample volumes that is simple, robust, and versatile. It is a fluidic device that partitions a sample by exploiting the interplay between fluidic forces, interfacial tension, channel geometry, and the final stability of the formed droplet and/or discretized volume. These compartmentalized volumes allow for isolation of samples and partitioning into a localized array that can subsequently be manipulated and analyzed. The isolation of the discretized volumes along with the device'"'"'s inherent portability render our invention versatile for use in many areas, including but not limited to PCR, digital PCR, biological assays for diagnostics and prognostics, cancer diagnosis and prognosis, high throughput screening, single molecule and single cell reactions or assays, the study crystallization and other statistical processes, protein crystallization, drug screening, environmental testing, and the coupling to a wide range of analytical detection techniques for biomedical assays and measurements. The minimal fluid interconnects and simple flow geometry makes the device easy to use and implement, economical to fabricate and operate, and robust in its operations.

Claims

1. A method comprising:

providing a fluidic lattice comprising,

a flow channel having a flow axis, and

a plurality of fluidic harbors in fluidic communication with the flow channel and offset from the flow axis;

flowing a first continuous liquid through the fluidic lattice to provide the first liquid within the plurality of fluidic harbors; and

flowing a second continuous liquid through the fluidic lattice, the second continuous liquid immiscible with the first liquid such that the second liquid displaces the first liquid from the flow channel while allowing the first liquid to remain in the plurality of fluidic harbors.

2. The method of claim 1 wherein the first liquid comprises an aqueous solution.

3. The method of claim 1 wherein the second liquid is flowed at a fast rate to displace some of the first liquid from at least one of the plurality of fluidic harbors.

4. The method of claim 1 further comprising:

prior to flowing the first continuous liquid, flowing a primer continuous liquid through the fluidic lattice, wherein the primer liquid is immiscible with the first liquid such that flowing the first liquid displaces at least a portion of the primer liquid from the flow channel and from the plurality of fluidic harbors.

5. The method of claim 4 wherein the first liquid comprises an aqueous solution.

6. The method of claim 4 wherein the first liquid is flowed at a fast rate to displace less than all of the third liquid from at least one of the plurality of fluidic harbors.

7. The method of claim 1 wherein the first liquid comprises an analyte, the method further comprising performing analysis of the first liquid within at least one of the plurality of fluidic harbors.

8. The method of claim 7 wherein the analyte comprises a biological material.

9. The method of claim 8 wherein the biological material is selected from a cell, a virus, a prion, a nucleic acid, a protein, a genetic material, an expressed product of a genetic material, a crystallizing molecule, or a particle.

10. The method of claim 8 wherein performing the analysis comprises performing biochemical analysis.

11. The method of claim 7 wherein the first fluid comprises a plurality of strands of nucleic acid and a volume of the flow channel and the plurality of fluidic harbors is configured such that either one nucleic acid strand or no nucleic acid strands are contained within each of the plurality of fluidic harbors, the method further comprising performing digital polymerase chain reaction (PCR) within the plurality of fluidic channels.

12. The method of claim 7 wherein the analyte undergoes crystallization in the fluidic harbor.

13. The method of claim 7 wherein the analyte contains at least one rare cell selected from cells expressing a malignant phenotype, fetal cells, circulating endothelial cells, tumor cells, cells infected with a virus, cells transfected with a gene of interest, or aberrant subtypes of T-cells or B-cells present in the peripheral blood of subjects afflicted with autoimmune or autoreactive disorders.

14. The method of claim 1 wherein a shape of at least one of the plurality of fluidic harbors is other than spherical

15. The method of claim 14 wherein a cross-section of at least one of the fluidic harbors is T-shaped, L-shaped, triangular, rectangular, circular, elliptical, polygonal, or square.

16. The method of claim 1 wherein at least one of the plurality of fluidic harbors is displaced in a vertical direction above the flow axis, in order to retain a buoyant species

17. The method of claim 1 wherein at least one of the plurality of fluidic harbors is displaced in a vertical direction below the flow axis, in order to retain a dense species

18. The method of claim 1 further comprising modifying a surface of at least one of the fluidic harbors to affect its interaction with the first liquid and/or the second liquid.

19. The method of claim 1 further comprising delivering a material or an energy to the at least one of the plurality of fluidic harbors through an auxiliary channel.

20. The method of claim 1 wherein the plurality of fluidic harbors are arranged in parallel, in series, or in both parallel and in series along the flow channel.

21. The method of claim 1 further comprising causing a contents of one of the plurality of fluidic harbors to mix with a chemical.

22. The method of claim 21 wherein the mixing results from breaking down a wall between the one of the plurality of fluidic harbors, and a chamber containing the chemical.

23. The method of claim 22 wherein the chamber is located out of a plane defined by the flow channel.

24. The method of claim 1 further comprising removing a contents including the first liquid, from at least one of the plurality of fluidic harbors.

25. The method of claim 23 wherein the contents are removed through an access channel.

26. The method of claim 24 wherein the contents are removed by flowing another continuous liquid through fluidic lattice, the another continuous liquid immiscible with the contents.

27. The method of claim 26 wherein a viscosity of the another continuous liquid is different from a viscosity of the contents.

28. The method of claim 26 wherein the another continuous liquid includes a surfactant.

29. The method of claim 24 wherein the contents are removed by an application of force to the contents of the at least one of the fluidic harbors.

30. The method of claim 29 wherein the force is selected from at least one of thermal energy, vacuum, pneumatic pressure, acoustic pressure, ultrasonic pulses, radiation pressure, electromagnetic field, electrowetting, photo-induced surface wetting, electrocapillarity, surface or interfacial tension, thermal-gradient-derived forces, electrostatic interaction, optical forces, or magnetic forces.

31. The method of claim 24 wherein the contents are removed utilizing a valve.

32. The method of claim 24 wherein the contents are removed by piercing the fluidic lattice with a needle.

33. The method of claim 24 further comprising further manipulating the contents removed from the one of the plurality of fluidic harbors.

34. An apparatus comprising:

a flow channel having a flow axis, the flow channel in selective fluid communication with a source of a first continuous liquid, and in selective fluid communication with a source of a second continuous liquid immiscible with the first liquid; and

a plurality of fluidic harbors in fluidic communication with the flow channel and offset from the flow axis.

35. The apparatus of claim 34 wherein a shape of at least one of the plurality of fluidic harbors is other than spherical

36. The apparatus of claim 35 wherein a cross-section of at least one of the fluidic harbors is T-shaped, L-shaped, triangular, rectangular, or square.

37. The apparatus of claim 34 wherein at least one of the plurality of fluidic harbors is displaced in a vertical direction above the flow axis, in order to retain a buoyant species within the first liquid.

38. The apparatus of claim 34 wherein at least one of the plurality of fluidic harbors is displaced in a vertical direction below the flow axis, in order to retain a dense species within the first liquid.

39. The apparatus of claim 34 wherein a surface of at least one of the fluidic harbors is modified to affect its interaction with the first liquid and/or the second liquid.

40. The apparatus of claim 34 wherein the plurality of fluidic harbors are arranged in parallel, in series, or in both parallel and in series along the flow channel.

41. The apparatus of claim 34 further comprising a secondary channel in fluid communication with at least one of the plurality of fluidic harbors.

42. The apparatus of claim 34 further comprising a secondary channel configured to deliver a material or an energy proximate to at least one of the plurality of fluidic harbors.

43. A method of performing digital polymerase chain reaction (PCR), the method comprising:

providing a fluidic lattice comprising,

a flow channel having a flow axis, and

a plurality of fluidic harbors in fluidic communication with the flow channel and offset from the flow axis;

flowing a first continuous liquid through the fluidic lattice, wherein the first continuous liquid contains a plurality of nucleic acid strands such that either only one nucleic acid strand or no nucleic acid strand is provided within each of the plurality of fluidic harbors;

flowing a second continuous liquid through the fluidic lattice, the second continuous liquid immiscible with the first liquid such that the second liquid displaces the first liquid from the flow channel while allowing the first liquid to remain in the plurality of fluidic harbors;

performing a plurality of heating cycles of the first fluid within the plurality of the fluidic harbors; and

detecting a concentration of the nucleic acid strands within the plurality of the fluidic harbors.