Protein Standards and Ladders Selection Guide

View all available protein ladders

Find the right protein ladder for your application and gel system. Use the interactive tool below to see our recommended protein ladders migration in the different gel chemistries.

Why the molecular weight changes between the different gel chemistries?

Slight differences in protein mobilities will occur when the same proteins are run in different SDS-PAGE buffer systems (e.g. Bis-Tris vs Tris-glycine). Each SDS-PAGE buffer system has a different pH, which affects the charge of a protein and its binding capacity for SDS. The degree of change in protein mobility is usually small in natural proteins but is more pronounced with atypical or chemically modified proteins, such as pre-stained standards. Apparent molecular weight values for pre-stained standards will vary between gel systems- it is important to use the apparent molecular weights that matches your gel for the most accurate calibration of your sample proteins.