Methods and apparatus for sorting cells using an optical switch in a microfluidic channel network
View Patent ↗Apparatus and Methods are provided for a microfabricated fluorescence activated cell sorter based on an optical switch for rapid, active control of cell routing through a microfluidic channel network. This sorter enables low-stress, highly efficient sorting of populations of small numbers of cells (i.e., 1000-100,000 cells). The invention includes packaging of the microfluidic channel network in a self-contained plastic cartridge that enables microfluidic channel network to macro-scale instrument interconnect, in a sterile, disposable format.
1. An integrated structure for microfluidic analysis and sorting comprising:
a cartridge, the cartridge comprising
an optical window,
a plurality of reservoirs, including at least:
a sample reservoir,
a fluid reservoir,
a waste reservoir, and
a target collection reservoir,
a chip, the chip including at least:
a sample inlet channel, the cell inlet channel being fluidically coupled to the sample reservoir,
one or more fluid inlet channels, the fluid inlet channels being fluidically coupled to the fluid reservoir,
a detection region,
a branched sorting region, and
at least two outlet channels including at least a waste channel and a target channel, waste channel being fluidically coupled to the waste reservoir and the target channel being coupled to the target collection reservoir,
the chip being disposed adjacent the optical window, and
a lid, the lid including at least:
a pneumatic pressure port, the port having an inlet and being coupled to at least one of the sample reservoir and the fluid reservoir, and
a filter disposed between the inlet of the pneumatic pressure port and at least one of the sample reservoir and the fluid reservoir,
a detector adapted to detect cells of a given state and to generate a signal in response thereto, and
a lateral force switch coupled to the detector and actuatable in response to the signal, the lateral force switch comprising a laser spot configured to be translated down the length of the detection region at an angle relative to a flow stream through the detection region;
whereby when a cell of a given state is detected, the lateral force switch is activated to sweep the laser spot alongside the cell as it flows to provide a lateral force on the cell so as to move the cell such that it selectively exits into the one of the at least two outlet channels.
2. The integrated structure for microfluidic analysis and sorting of claim 1 wherein the sample reservoir is conical.
3. The integrated structure for microfluidic analysis and sorting of claim 1 wherein the sample reservoir is tapered.
4. The integrated structure for microfluidic analysis and sorting of claim 1 wherein the sample reservoir further includes an insert.
5. The integrated structure for microfluidic analysis and sorting of claim 1 wherein the insert is a polypropylene insert.
6. The integrated structure for microfluidic analysis and sorting of claim 1 wherein the lid is plastic.
7. The integrated structure for microfluidic analysis and sorting of claim 6 wherein the lid is acrylic plastic.
8. The integrated structure for microfluidic analysis and sorting of claim 1 wherein the lid includes separate pneumatic pressure ports for the sample reservoir and the fluid reservoir.
9. The integrated structure for microfluidic analysis and sorting of claim 8 wherein the lid includes a pneumatic pressure port for the target collection reservoir.
10. The integrated structure for microfluidic analysis and sorting of claim 8 wherein the lid includes a pneumatic pressure port for the waste reservoir.
11. The integrated structure for microfluidic analysis and sorting of claim 1 wherein the lid includes a pneumatic pressure port for the target collection reservoir.
12. The integrated structure for microfluidic analysis and sorting of claim 1 wherein the lid includes a pneumatic pressure port for the waste reservoir.
13. The integrated structure for microfluidic analysis and sorting of claim 1 wherein the lid provides optical access to the reservoirs.
14. The integrated structure for microfluidic analysis and sorting of claim 1 wherein the lid includes snap-on attachments to couple to the cartridge.
15. The integrated structure for microfluidic analysis and sorting of claim 1 wherein the filter is gas permeable.
16. The integrated structure for microfluidic analysis and sorting of claim 15 wherein the filter is fluid impermeable.
17. The integrated structure for microfluidic analysis and sorting of claim 1 wherein the filter is fluid impermeable.
18. The integrated structure for microfluidic analysis and sorting of claim 1 wherein the filter is a polypropylene filter.
19. The integrated structure for microfluidic analysis and sorting of claim 1 wherein curable adhesive is disposed between the chip and the cartridge.
20. The integrated structure for microfluidic analysis and sorting of claim 1 wherein the adhesive is UV curable.
21. The integrated structure for microfluidic analysis and sorting of claim 1 further including a bonding sheet between the chip and the cartridge.
22. The integrated structure for microfluidic analysis and sorting of claim 21 wherein the bonding sheet is a pressure sensitive adhesive.
23. The integrated structure for microfluidic analysis and sorting of claim 1 wherein optical access to the chip is provided through the optical window and through the reverse side of the chip.
24. The integrated structure for microfluidic analysis and sorting of claim 1 wherein the sample reservoir is adapted to contain from 10 to 30 microliters.
25. The integrated structure for microfluidic analysis and sorting of claim 1 wherein the fluid reservoir is adapted to contain 500 to 1,500 microliters.
26. The integrated structure for microfluidic analysis and sorting of claim 1 further including a gasket between the lid and cartridge.
27. The integrated structure for microfluidic analysis and sorting of claim 1 wherein the waste reservoir contains non-target materials.
28. The integrated structure for microfluidic analysis and sorting of claim 1 wherein the waste reservoir contains excess fluid.
29. The integrated structure for microfluidic analysis and sorting of claim 1 wherein the chip and cartridge comprise two separate structures.
30. A method for cell sorting in a device having an inlet, a fluidically coupled channel, and at least two fluidically coupled outputs, comprising the steps of:
receiving a cell in a fluidic medium at an inlet,
flowing the cell through a fluidic channel,
subjecting the cell to a bias flow resulting in collection in a first reservoir,
identifying a cell to be sorted through application of a lateral force into a second reservoir, and
applying a lateral force on the cell, the lateral force comprising a laser spot configured to be translated at a non-zero angle down the fluidic channel toward the at least two outputs and characterized in that the lateral force is a non-trapping force and in that the lateral force is moved alongside a selected cell as it flows down the fluidic channel, thereby increasing the total interaction time between the lateral force and the cell, whereby the cell selectively exits into the outlets.
31. The method for cell sorting of claim 30 wherein the laser illumination is moved linearly along the channel in proximity to the cell as it flows through the channel.
32. The method for cell sorting of claim 30 wherein the laser illumination is moved diagonally along the channel in proximity to the cell as it flows through the channel.