I want to use a native gradient gel to separate proteins of sizes up to 100 kDa. What % of PA can I use?

Answer 1

I generally get good results with a 10% gel, but this is for denaturing SDS-PAGE. This *might* work for native PAGE, but your mileage may vary depending the proteins you are separating, especially if they are part of a complex. Bio-Rad suggests 8-16% gradient; take a look at the images on the Bio-Rad page below, that may be helpful. You should also look at Bio-Rad's protein standards page, there is a set of figures in there that show how their standards migrate in various gels.

Answer 2

You should post this in the biology section, probably have better luck.