Re: UV excitable ab conjugates

Mario Roederer (Roederer@Darwin.Stanford.EDU)
Wed, 03 Jul 1996 10:37:57 -0700

> Does anyone know of a fluorochrome conjugated to mab or
> strepavidin that is UV excitable? I do know that BD
> sells a probe called AMCA that they used to custom
> conjugate to strepavidin, but they no longer offer that
> service, apparently. I need a good 4th color probe to
> use on a system with 2 argon lasers - UV and 488. Any
> suggestions would be appreciated.

Both AMCA and Cascade Blue are UV excitable and can be conjugated to antibodies
(or avidin). Unfortunately, they are quite dim--and will work really only for
the brightest antibodies (i.e., high antigen density). CasBlu-Avidin should
also work reasonably well. CasBlu reactive dye is sold by Mol Probes, and the
conjugation is as easy as FITC.

If you have the option, you can get one of the new Krypton lasers which have 406
nm emission lines--these efficiently excite Cascade Blue, and make CasBlu
conjugates as "bright" (over autofluorescence) as FITC conjugates.

mr