Air-over-liquid “Flow shift” method
On-chip Sort uses a small disposable microfluidic chip (with either 80 µm or 150 µm flow channel width) as the core of its technology. Sample and sheath fluid are loaded into the sample and sheath reservoirs on the chip, respectively. Unlike conventional cell sorters, which a specific sheath fluid has to be used, On-chip Sort allows for the use of any sheath fluid appropriate to your cells (e.g., culture medium, fresh water, sea water, oil).
Cell sorting on On-chip Sort utilizes the ‘Flow shift’ mechanism. When a detected target cell reaches close to the sorting area, a short liquid pulse is generated by pressurization of air to deflect the target cell into the collection reservoir. Non-target cells flow in a continuous flow to the waste. This sorting method does not involve the use of high pressure, nozzle, electric charges or high-speed collision, which are the inherent problems of other sorting techniques.
All the liquids (sample, sheath and waste) remain inside the chip during analysis and sorting, and there are no external tanks. Fluids in channels and reservoirs do not come in contact with the instrument itself, and thus there is no sample-to-sample contamination or contamination to the instrument. Chips are available unsterilized or sterilized.
Jet-in-air or Cuvette hybrid cell sorters have multiple processes that triggers sorter-induced cellular stress (SICS). On-chip Sort allows for much gentler sorting of cells compared to conventional sorters because the use of microfluidic chip has eliminated such damaging steps.
||Cells collide at high-speed when collected
||Cells are stressed due to charging
||No electrostatic charging
||Potentially hazardous for users
||Must use specified sorting medium
||Most standard media accepted
||Post-sort wash with harsh chemicals
||No post-sort washing