A diagram of a generalized cell sorter (A). Particles are introduced into a
column of pressurized sheath fluid, and as they emerge from the nozzle, they pass
through one or more laser beams. At this point, the moment of analysis, the cytometer
gathers information about the fluorescence characteristics of the particle. After passing
through the stream for the break-off distance, the stream is charged when the cell breaks
off into a drop (moment of charging). There will be a variable number of satellite drops
that are formed from the fluid connecting the drops as they form. These satellites should
be “fast-merging” (i.e., quickly become coalesced with the preceding drops). Charged
drops then pass through two high-voltage deflection plates and are deflected into
collection vessels or aspirated to waste. The break-off point is seen in real time under
stroboscopic illumination