On-chip microfluidic processing of particles
Described herein are microfluidic devices and methods that can greatly improve cell quality, streamline workflows, and lower costs. Applications include research and clinical diagnostics in cancer, infectious disease, and inflammatory disease, among other disease areas.
1. A microfluidic device comprising:
(a) a channel extending from a plurality of inlets to a plurality of outlets, wherein the channel is bounded by a first boundary wall and a second boundary wall opposite from the first boundary wall; and
(b) an array of obstacles arranged in rows and columns disposed within the channel wherein subsequent rows of the obstacles are offset from each other by a tilt angle greater than zero, and wherein particles above a critical size are deflected by the obstacles toward the second boundary wall when the particles are flowed from the inlets to the outlets;
wherein the device is configured such that the particles are inputted into at least one of the plurality of inlets and are deflected through a series of parallel flow streams flowing from the plurality of inlets to the plurality of outlets while being deflected toward the second boundary wall, and
wherein the series of parallel flow streams comprises a first reagent flow stream comprising a first binding agent, a second reagent flow stream comprising a fixation agent, a third reagent flow stream comprising a permeabilization reagent, and a fourth reagent flow stream comprising a second binding agent, wherein the first binding agent comprises a first detectable label, and wherein the second binding agent comprises a second detectable label.
2. The device of claim 1 , wherein the particles are cancer cells, or leukemia cells.
3. The device of claim 1 , wherein the particles are leukocytes, a subtype of leukocytes or stem cells.
4. The device of claim 3 , wherein at least one of the binding agents is an antibody.
5. The device of claim 3 , wherein the first and second detectable label comprise different labels.
6. The device of claim 3 , wherein each of the reagent flow streams is separated by a wash stream comprising a wash buffer.
7. The device of claim 3 , wherein the particles deflected toward the second boundary wall comprise particles above a critical size of about 5 μm.
8. The device of claim 7 , wherein the device comprises only a single array of obstacles.
9. The device of claim 1 , further comprising an analytical device in fluid communication with at least one of a plurality of outlets, wherein the analytical device is configured to perform an analysis of particles processed by the device.
10. The device of claim 9 , wherein the analytical device comprises a flow cytometer or a mass spectrometer.
11. The device of claim 1 , wherein the obstacles are arranged in rows and columns, wherein the rows define an array direction that differs from the flow of the plurality of parallel flow streams by a tilt angle (ϵ) that has a magnitude greater than zero and less than or equal to ⅓ radian, the obstacles in each respective column defining gaps between the obstacles through which the fluid flows generally transversely with respect to the columns, and wherein the obstacles are shaped such that surfaces of two obstacles defining a respective gap are asymmetrically oriented about a first plane that extends through the center of the respective gap and that is parallel to the flow of the plurality of parallel flow streams.
12. The device of claim 11 , wherein the array of obstacles comprises at least one separator wall oriented parallel to flow of the plurality of flow streams and the first and second boundary walls, wherein the particles introduced into an sample inlet near the first wall pass through the plurality of flow streams while being deflected toward the second wall.
13. The device of claim 12 , wherein the at least one separator wall is positioned between the first and second boundary walls to delay the flow of deflected particles toward the second wall, wherein the delay serves to substantially increase an amount of time that deflected particles reside in a flow stream, and/or substantially reduce mixing between parallel flow streams.
14. A microfluidic device comprising:
(a) a channel extending from a plurality of inlets to a plurality of outlets, wherein the channel is bounded by a first boundary wall and a second boundary wall opposite from the first boundary wall; and
(b) an array of obstacles arranged in rows and columns disposed within the channel wherein subsequent rows of the obstacles are offset from each other by a tilt angle greater than zero, and wherein particles above a critical size are deflected by the obstacles toward the second boundary wall when the particles are flowed from the inlets to the outlets;
wherein the device is configured such that the particles are inputted into at least one of the plurality of inlets and are deflected through a series of parallel flow streams flowing from the plurality of inlets to the plurality of outlets while being deflected toward the second boundary wall, and
wherein the device further comprises a plurality of reservoirs in fluid communication with the inlets wherein at least one reservoir comprises a first labeling reagent and there are at least three additional reservoirs comprising one or more of:
i) a sample comprising particles;
ii) a buffer;
iii) a second labeling reagent different from the first labeling reagent and comprising either a cell surface label or an intracellular label;
vi) a fixation agent;
vii) a permeabilization reagent; or
viii) a binding reagent;
or any combination thereof.
15. The device of claim 14 , wherein the particles are leukocytes.
16. The device of claim 15 , wherein the leukocytes are T cells.
17. The device of claim 14 , wherein the particles are stem cells.
18. The device of claim 14 , wherein the first labeling reagent or the second labeling reagent comprises an antibody.
19. The device of claim 18 , wherein the antibody specifically recognizes leukocytes.
20. The device of claim 19 , wherein the antibody specifically recognizes T cells.
21. The device of claim 20 , wherein the antibody specifically recognizes mature T cells.
22. The device of claim 21 , wherein the antibody specifically recognizes immature T cells.
23. The device of claim 14 , wherein the first labeling reagent comprises a cell surface label and the second labeling reagent comprises an intracellular label.
24. The device of claim 14 , wherein the first labeling reagent comprises an intracellular label and the second labeling reagent comprises a cell surface label.
25. The device of claim 24 , wherein the permeabilization agent comprises a detergent, an alcohol, or a membrane-disrupting toxic.
26. The device of claim 14 , wherein the binding reagent comprises an antibody.
27. The device of claim 26 , wherein the antibody specifically recognizes leukocytes.
28. The device of claim 27 , wherein the antibody specifically recognizes T cells.
29. The device of claim 14 , wherein the fixation agent comprises formaldehyde, gluteraldehyde, methylalcohol, ethylalcohol, phosphate-buffered formalin, formal calcium, formal saline, unbuffered zinc formalin, Zenker's fixative, Helly's fixative, B-5 fixative, Bouin's solution, Hollande's solution, Gendre's solution, Clarke's solution, Carnoy's solution, Methacarn, alcoholic formalin, or formol acetic alcohol.