Schematic and principle of μFACS
We have extended the principle of optical tweezers as a noninvasive technique to actively sort hydrodynamically focused cells based on their fluorescence signal in a microfluidic device. This micro fluorescence-activated cell sorter (µFΑCS) uses an infrared laser to laterally deflect cells into a collection channel.
Schematic of μFACS based on optical forces. (A) Instrument layout with laser-induced fluorescence (LIF) excitation and emission paths, forward scattering detection, optical tweezers, and world-to-chip interface. (B) Microfluidic chip of two independent sorting modules with inlets on the left and outlets on the right. (C) Close-up view on flow cytometry and sorting regions of the chip where sample (blue dye) is hydrodynamically focused by two neighboring sheath flows (yellow) and split between a waste (left) and collection channel (right). The two hairpin turns reorient both channels into the field of view to visually confirm sorted cells.
Optical sorting of macrophage cells 40X slower (1.34MB WMV)
Cell sorter animation (110KB Flash animation)
Perroud, T. D.; Kaiser, J. N.; Sy, J. C.; Lane, T. W.; Branda, C. S.; Singh, A. K.; Patel, K. D. Microfluidic-Based Cell Sorting of Francisella tularensis Infected Macrophages using Optical Forces. Analytical Chemistry 80, 6365-6372 (2008).