re: sort purity
Michael Fox (MFox@vines.colostate.edu)
Wed, 19 Jan 94 8:55:56 MST
In regard to your sorting purity problem, there are several possibilities
that may be affecting your results. First, do you get essentially 100%
purity when you sort beads instead of cells? If so, then the sorting is
probably working properly. Are you running the sample through at a very high
rate? This would affect sorting purity, if you are getting a lot of
coincidences, even if you are trying to correct for them. Are your cells
very large? Large cells disrupt the droplet formation (see article by
Harkins and Galbraith, Cytometry 8:60-80 (1987), and can dramatically affect
sorting purity. Finally, if you are gating the population through a series
of gates, be aware that you have to mimic all of the collection gates with
sort gates. If you are just setting sort gates on the final gated
population, the sorted population will not be gated on any of the other gates
you set. This can lead to large errors. Many instrument manufacturers do
not point this out very clearly, if at all.
Good luck.
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