Receipe for pre-stained protein molecular marker

[Dr Engelbert Buxbaum]

Lei Wan wrote:

> Does anyone know how to prepare a pre-stained protein molecular
> marker?
> As you know it is quite expensive here in Taiwan, I am a short of
> budget for my research. I am looking for all possible way to cut down
> my cost.

I have used IAEDANS (Fluka, Molecular Probes), a fluorescent SH-reactive
dye, to make standards. The coupling is performed in 100 mM NaHCO3 as
buffer, incubation 1 h at 37 degrees in the dark, then add
mercaptoethanol to bind excess dye and dialyse. Any other dye coupled to
the iodoacetamido-group should also work. 

But whether in the end you save any money is a different question,
especially if you take the working time spend on it into account.