alexa fluor

Nebe-Von-Caron, G g.nebe-von-caron at
Thu Jan 10 11:01:23 EST 2008

You could use a mixed goat and rat serum blocking to reduce cross
species recognition, but considering how easy it is to label your
antibody directly with either PE or APC using for example the Innova
biosciences kits I would go that route instead, unless you absolutely
need those colour channels for other antibodies. 

There are still unwanted interactions via Fc receptors, anti species
reactions, rheumatoid factors, fibrinogen etc and entrapment in dead
cells to be considered.

Gerhard Nebe-von-Caron 
Research Scientist and Biomedical Engineer 
Swiss Precision Diagnostics 
Priory Business Park 
Bedford, MK44 3UP, UK 
Tel +44(0)1234-835474 
Fax +44(0)1234-835002 
mailto:g.nebe-von-caron at 

-----Original Message-----
From: Andy Hoffman [mailto:andrew.hoffman at] 
Sent: 07 January 2008 20:08
To: cyto-inbox
Subject: alexa fluor 

A simplistic question from a relative novice flower:

Do polyclonal secondaries conjugated to Alexa Fluors (e.g. Alexa Fluor 
647 goat anti-mouse IgG (H+L) A21236 - InVitrogen/Mol Probes) that are 
supposed to be 'highly absorbed' against alternative species (e.g. rat) 
actually cross-react with rat anti-mouse secondaries at certain 
concentrations?  Can they pick up unstained cells in the absence of 
other primaries/controls?   Lastly, is it suggested to wash after the 
first round of primary + secondary-alexa, then block with normal mouse 
Ig as previously mentioned in the CD133 string, before adding other 
primaries?    Thanks so much for your time


Andrew M. Hoffman, D.V.M., D.V.Sc., 
Diplomate, A.C.V.I.M. (Large Animal Medicine)
Associate Professor 
Cummings School of Veterinary Medicine
Tufts University
Director, Lung Function Testing Laboratory
Department of Clinical Sciences
Bldg 21, Suite 110
200 Westboro Road
North Grafton, MA 01536
andrew.hoffman at
Phone (508) 887 4589
Fax (508) 887 4590

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