I'm about to do some immuno-staining and want to use FITC and TRITC labelled antibodies.  I've heard that fixing cells with 4% paraformaldehyde may give me pretty high background and may interfere with the staining.  Does anyone know if that's true, or why that happens?  Is there a different fixative that I can use that would prevent this?

Thanks for the help!
Sylvia Poulos
USDA-ARS-Animal Physiology Rese