How long can you store Trypsin powder at -20°C?

18 April 2021 1 9K Report

I have Trypsin powder that has been in storage at -20°C since around March 2018. It is stored in a centrifuge tube in its powder form. Will it still be viable after I prepare it in a solution?

Julien Berlureau

Only 2 years late.

One of my lab coworker gave me Trypsin powder from the late 80's, it was well conserved at -20°c since then, in its original packaging, itself in a jam pot vacuum sealed.

I believe 3 years in an eppendorf shouldn't be that big of an issue.

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