Cells found contaminated upon thawing?

03 March 2019 1 8K Report

I froze the HEK 293 cells some 3 months ago in the Synth-a-freeze medium. When i started thawing them back they are heavily contaminated with bacterial growth. i have lost 4 aliquotes now due to this. What could be the reason for such a contamination. I'm Using 2 ml Corning Cryovials

Thanks!!

Andreas Eisenreich

Most likely a contamination in your freezing material/medium. Thus, the complete charge should be discarded and replaced by fresh cells. Moreover, you should test your media and cell culture (including apparatures).

Good luck.

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