Tricine PAG - (Mar/06/2012 )

I've read that adding glycerol to tricine gel doesn't have an effect on separating proteins and it is used only to increase the density of solutions and facilitate gel casting . But I doubt this. I made two variants of 10% Tricine gels that have only different glycerol concentration (10,6% & 8%). The gel with 8% glycerol showed bands with good resolution but the lowest band was about 10 kDa, human insulin marker didn't appear. The other gel showed insulin band and even a band below it (~3kDa), but the resolution of bands was much worse.
Maybe anyone can advise me how to solve the problem with resolution or give other good advises about tricine SDS PAGE?

you can add 6M urea to sharpen bands or run a gradient gel (we like 10-16 or 10-20%, depending on how low we need to go).