Finding suitable Acrylamide/Bis-acrylamide ratio - (Sep/17/2015 )

Hi guys,

I will be doing protein expression work and will need to run SDS soon.

Right now I am working on a 27 kDa protein and soon my work will be on a 63kDa protein.

But I am confused to which ratio of acrylamide/Bis-acrylamide premixed solution (Biorad) to buy.

How do I know which ratio is suitable for my protein? 

Thanks.

These sound like very typical protein sizes, so a normal 19:1 ratio would probably work well.

i've always found that 37.5:1 is pretty standard for protein page although thermo-fisher seems to recommend 19:1.

however, i think you are also asking what should be the total acrylamide concentration for the gel. assuming that you are only interested in the 2 sizes you give, you can probably use a 10 or 12% gel.

see this chart for tris-glycine sds-page gels from thermo-fisher.