What you measure in all cases is not viability but membrane
integrity by dye exclusion. This can be impaired temporarily
by electro or chemo-poration processes. Also solvents or
active pinocytosis can interfere with dye exclusion
properties. In the later case dye retention might be an
alternative way of measurement.
Another point to consider is the time and dye concentration
used. Both, long staining time or high concentration will
eventually lead to staining.
As a more aggressive scheme you might want to add some
DNAse. If that can nibble you DNA of the cells away you know
that the cells definitively had it.
Regards
Gerhard
______________________________ Reply Separator _________________________________
Subject: Viability / nuclear stain
Author: suedemag@uci.edu at INTERNET
Date: 09/03/1999 20:29
Has anyone used anything other than PI to do viability staining on the FLOW?
7-AAD?
I have a researcher using PI and AO and they co-stain ALL the cells, virtually
100%, in what they believe to be live samples of Chondrocytes. Any hints?
Does the collagenase used to break up the matrix of the cartilage cause
permeabilization? I'm kind of at a loss to explain to him what is happening.
Any better dye for this application?
Thanks in advance!
Susan DeMaggio, MS BSMT(ASCP)QCym
Resource Manager
Optical Biology Shared Resource
University of California, Irvine
Irvine, CA 92697-2275
phone 949-824-4110
fax 949-824-3571
<http://mamba.bio.uci.edu/~suedemag/OBCore/index.htm>http://mamba.bio.uci.e
du/~suedemag/OBCore/index.htm
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