Peptides are typically shipped as dry lyophilized powders within sterile vials. The peptides are protected from degradation by a vacuum seal and an atmosphere of dry inert gas, usually nitrogen. The peptides are typically stored frozen at -20° and away from light for long-term stability. However, some peptides are more unstable and degrade quickly in solution, particularly if they contain Cys or Met residues that can react with oxygen and cause oxidation and decomposition. The best way to avoid this is to store peptides in a dessicator and in small aliquots in the freezer, and to limit the number of freeze-thaw cycles.
To reconstitute a peptide in a solvent, first sterilize your workspace with alcohol prep wipes and remove the peptide vial tops. Then, prepare a vial of bacteriostatic water and a syringe. Make sure the syringe has a needle that is compatible with your peptide, and insert it into the center of the bacteriostatic water vial.
Gently tap or shake the peptide to help it dissolve. If you have access to a sonicator, this can accelerate the dissolution process. However, remember that excessive shaking can damage the peptide structure and lead to a loss of peptide, especially at high dilutions.
If you are working with a highly reactive peptide, it is a good idea to use a syringe-tip filter to ensure no impurities such as copper or nickel are introduced to the peptide during reconstitution. This can also significantly reduce the risk of contamination and ensure a clean injection in the target site.
It is also important to choose a solvent that is compatible with the peptide, as well as being chemically inert and optically clear. Choosing a glass container can provide the necessary protection for your peptides and is highly recommended for long term storage. However, if you are only working with short-term samples plastic vials can be used as they are more durable and less likely to be damaged by organic solvents.
Once the peptide is fully dissolved in the solvent, it is ready for injection. To prepare for this, sterilize the insulin syringe and the tip of the syringe with more alcohol wipes and remove the syringe cap from its vial. To prevent foaming, it is a good idea to gently roll the syringe and nozzle in your hands and to avoid tapping or forceful shaking.
Lastly, use the provided peptide reconstitution calculator to determine how many tick marks you will need to withdraw from your reconstituted peptide and then fill your syringe with this amount of solvent. Once you are finished, it is a good idea to dispose of the syringe and needle in a sharps container.
If you need more peptide vials or are looking for different sizes, Peptide Sciences offers an extensive selection of peptide and hormone research supplies. Visit our shop today to order yours!