splitting cells

[RUTH MCMAHON]

I have always been taught to wash cells with PBS before using trypsin 
to wash off FCS. However, I was in a rush today, had forgotten to 
heat up the PBS and used trypsin without washing. The cells split 
fine. 
So my question, is there a reason this is bad science?
Ruth.
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Ruth McMahon, PhD.,                                  Tel:    706-2815 
Biotechnology Centre,                                Fax:    269-2016
University College Dublin,
Belfield, 
Dublin 4,
Ireland.

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