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  • FAQ: Can I store competent cells at -20°C instead of -80°C?

    Competent cells should be stored at -80°C. Storage at -20°C will result in a significant decrease in transformation efficiency (TE). When tested on NEB 5-alpha Competent E.coli (NEB #C2987H), cells lost 94.5% of TE after only 24 hours of storage at -20°C. Cells lost 98.9% of TE after 2 days, and 99.6% of TE after one week of storage at -20°C.