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Preparing a protein for long-term storage

Today in the lab I was preparing a stock of a protein for long-term storage. First, using a syringe, a specific volume of an appropriate liquid (in this case, water) was added to the glass vial containing a lyophilised (i.e., powder) form of the protein, to turn it into a solution of the desired concentration. Then, the solution was aliquoted (i.e., divided) into small tubes. One of the tubes was used immediately for a biochemical assay. The rest were stored at -80°C for future use.

Preparing a stock of a protein.
Preparing a stock of a protein.

The protein must maintain its original biological or functional behaviour over an extended period of storage which may range from days to years, and all possible inactivation processes must be prevented. The shelf life of a protein depends on both the intrinsic nature of the protein and the storage conditions. Proteins must be stored at an appropriate temperature and pH range, and usually in the presence of concentrated glycerol, sucrose, or a similar substance, for the proteins to retain activity and prevent aggregation.