DAPI and APC

Dr. Howard Petrie (h-petrie@ski.mskcc.org)
Tue, 11 Feb 1997 17:39:51 -0400

Fellow flow cytometrists: We are working on a three laser Vantage
(Enterprise for UV/488 source, with rhodamine dye tuned to ca. 605nm; dye
and UV beams are colinear). We are having problems with DAPI (FL5, in
linear) spilling into the APC detector (FL4, log, with 660/20 filter).
According to the spectral data I have, DAPI should lose >95% of its
fluorescence by 575-580nm, but certainly by 600nm in any case. We are
using DAPI at the lowest concentration that will give tight CVs on fixed
cells with 2n DNA content. I can't figure out if we might have a bad batch
of DAPI, or something else. Does anyone else have experience using this
combination? Any ideas what gives? Thanks for your input, Howard

______________________________________

Howard T. Petrie, Ph.D.
Assistant Member, Immunology Program
Memorial Sloan-Kettering Cancer Center
Box 341, 1275 York Avenue
New York NY 10021

phone (212)639-2149
fax (212)794-4019
e-mail: h-petrie@ski.mskcc.org