Peptide Storage and Stability Protocol

Unopened lyophilized peptides should be stored at -20°C for maximum shelf life. Most lyophilized peptides are stable for 24-36 months at -20°C and 12-18 months at 2-8°C. Keep vials in their original sealed containers with desiccant packs to prevent moisture absorption.

Once reconstituted with bacteriostatic water, peptides should be stored at 2-8°C (standard refrigerator). Most reconstituted peptides maintain stability for 21-30 days, though some more stable peptides (such as BPC-157) may last up to 6 weeks. Always check the specific compound's stability data in its monograph.

Many peptides are photosensitive and can degrade upon exposure to UV or strong visible light. Wrap vials in aluminum foil or store in opaque containers. This is particularly important for peptides containing tryptophan, tyrosine, or methionine residues.

Always swab vial stoppers with 70% isopropyl alcohol before each access. Use a fresh, sterile syringe for every draw. Never use the same syringe to draw from multiple vials. Minimize the number of times you pierce the stopper — each puncture slightly increases contamination risk.

If you must freeze reconstituted peptides, aliquot the solution into single-use volumes before freezing. This avoids repeated freeze-thaw cycles, which cause protein aggregation and loss of activity. Use snap-freezing in liquid nitrogen or a -80°C freezer when possible.

Maintain a peptide inventory log recording: compound name, lot number, storage location, reconstitution date (if applicable), expiration date, and remaining volume. Regularly inspect stored peptides for changes in appearance, particulate matter, or color changes.