Storage Best Practices

Lyophilised peptide in a sealed vial is the most stable form. Stability studies generally report long shelf lives when powder is kept frozen, shorter but still substantial stability under refrigeration, and progressively shorter stability at room temperature.

Moisture is the enemy of lyophilised material. Vials are allowed to reach room temperature before opening so that condensation does not form on cold glass and powder.

Once a peptide is in solution, degradation begins. Refrigeration at 2–8 °C is the condition described in nearly all handling documentation, and usable windows are typically measured in weeks rather than months.

Repeated freeze-thaw cycles are specifically discouraged in stability literature, because ice crystal formation damages peptide structure. Where long-term storage of a solution is required, aliquoting into single-use portions before freezing is the described approach.

Peptide bonds and aromatic residues such as tryptophan and tyrosine are susceptible to photodegradation. Amber vials or storage in the original carton addresses this.

Oxidation affects sulfur-containing residues in particular. Compounds like glutathione are especially sensitive and are described as having notably shorter solution stability than typical peptides.