Akos, We have used beads from Spherotech (RFP-50-5) for counting both platelets and leukocytes in whole blood preparations (with/without red cell lysis) with excellent results. Of course, accurate and precise pipetting is critical. Lori Lori Krueger Center for Platelet Function Studies UMass, Worcester www.platelets.org ----- Original Message ----- From: Bourget, Lucie <Lucie.Bourget@nrc.ca> To: cyto-inbox Sent: Friday, May 12, 2000 10:36 AM Subject: RE: True count substitute > > I usually use flow-check or flow-set beads from Beckman-Coulter ( they are > at 1 X 10.6/mL). I put 10 uL in 1mL of cell suspension, I stop the analysis > on a 1000 beads ( equivalent to 100 uL of cell suspension), I just have to > multiply by 10 the number of cells ( in a specific gate) and I have the cell > concentration per mL. > > You just have to be carefull for cell aggregats, that is the same problem > for any counting techniques > Put aside a vial of beads for that specific purpose, vortex it well before > using and pay attention to tiny air bubbles when pipetting ( specially > following the vortexing ). > > > Lucie Bourget > > Flowcytometry > Biotechnology Research Institute > National Research Council Canada > Montréal, QC, H4P 2R2 > Tel: office 514-496-6274 lab 514-496-6330 > Fax: 514-496-5143 > > > > > -----Original Message----- > From: Arnold Pizzey [mailto:a.pizzey@ucl.ac.uk] > Sent: Thursday, May 11, 2000 4:31 AM > To: Cytometry Mailing List > Subject: True count substitute > > > At 09:21 09/05/00 -0400, you wrote: > > > > > > > >Dear Flowers, > > > >BD does not make the TruCount tubes available without > buying it with their > kits > >(that we do not need). Does anyone know a similar product > for cell > counting on a > >flow cytometer? > > > >Thanks, > > > >Akos Szilvasi > >Biogen, Cambridge, MA > > > > > > > > > > > Greetings Akos, > > I have been using the following method to obtain absolute > counts by flow; > > 1) centrifuge 5ml of Beckman-Coulter Flow-check > Fluorospheres 400g 10mins. > > 2) Discard supernatent and resuspend in 5ml fetal bovine > serum > > 3) centrifuge as above and resuspend in 5ml fetal bovine > serum > > 4) Count beads by haemocytometer (the hard part - I count > around 1000 beads) > > 5) Add beads to sample and analyse by flow. > > > regards, > > Arnold > > > _/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/ > Arnold Richard Pizzey > Department of Haematology > Royal Free and University College London Medical > School > 98 Chenies Mews > London WC1E 6HX > U.K > > voice: +44 020-7679-6234 > Fax: +44 020-7679-6222 > email: a.pizzey@ucl.ac.uk > > _/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/
This archive was generated by hypermail 2b29 : Wed Apr 03 2002 - 11:55:48 EST