FAQ: How should I store my protein after it is purified?

 Most proteins can be stored for at least a few days at 4°C without denaturing. For long term storage, one can either freeze at –70°C or dialyze into 50% glycerol and store at –20°C. When storing at –70°C, aliquot the protein so only the portion to be used must be thawed. Repeated freeze/thaw cycles will denature many proteins.