DTT effect on proteins when stored at -20°C?

10 June 2022 1 6K Report

Hi, I did an overnight digestion using an His-tagged HRV-3C protease, my antigen of interest and cleavage buffer (containing 50 mM Tris-HCl pH 7.5, 150mM NaCl, 1 mM EDTA, 5mM DTT). The final concentration of DTT in my sample is now 0.5 mM. Since I can´t use this sample for 5 days, can I just freeze it at -20°C, or this concentration of DTT could still affect my antigen at this temperature?

Thanks

Mu-Shen Chang

5~10mM DTT is recommended, not to mention if it is lower than that. In a short-term storage, number of freeze/thaw cycle is what should be considered, more than the storage temperature, -20 degree Celsius is ok for a one week keep, if longer I would suggest in -80.

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