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What can I do if low molecular weight proteins are not showing any bands in western blot?

Posted April 24, 2020


For proteins of low molecular weight (<20 kDa), it is possible for bands to not show in a western blot due to poor retention of the membrane and risk of over-transfer. This can be remedied by reducing the voltage or time for transfer, using a PVDF membrane instead of nitrocellulose, and using a membrane of smaller pore size (0.1-0.2 um). A heat-mediated blotting technique or semi-dry transfer can also be beneficial when working with low molecular weight proteins.

Additional resources

Gibbons J. (2014). Western blot: protein transfer overview. North American journal of medical sciences, 6(3), 158–159. doi:10.4103/1947-2714.128481