Hi Bushra, keratin comes from skin.. You have to wear gloves in all stages of your experiments.

Keratin is continuously shed from your fingers and the only way to keep keratin away from your experiments is to use gloves in everything you do.

Dear Bushra,

This is very useful:

Anal Chem. 1996 Mar 1;68(5):850-8.

Mass spectrometric sequencing of proteins silver-stained polyacrylamide gels.

Shevchenko A1, Wilm M, Vorm O, Mann M;

In-gel digestion for mass spectrometric characterization of proteins and proteomes.

Shevchenko A, Tomas H, Havlis J, Olsen JV, Mann M.

Nat Protoc. 2006;1(6):2856-60.

Thank you all for valuable advises!