Peptides are normally supplied as a fluffy, freeze-dried material in serum vials. Store peptides in a freezer after they have been received. In order to reconstitute the peptide, distilled water or a buffer solution should be utilized.
Some peptides have low solubility in water and must be dissolved in other solvents such as 6 to 10% acetic acid for a positively charged peptide
Use the minimal amount of these non-aqueous solvents and add water or buffer to make up the desired volume. After peptides are reconstituted, they should be used as soon as possible to avoid degradation in solution.
The long-term storage of peptide samples presents a somewhat different problem. Lyophilized peptides generally have excellent stabilities (in most cases, lyophilizates can be stored for years at -10 C or lower temperatures with little or no degradation),
but, in solution, they generally have much more limited stabilities. Since peptides are susceptible to degradation by proteases of bacterial or microbial origin, the first rule is to prepare sterile solutions, either by reconstitution in sterile, distilled water, or by sterile filtration after reconstitution