How long does a reconstituted peptide remain stable in bacteriostatic water?

Most lyophilized peptides reconstituted in bacteriostatic water remain stable for roughly 3–4 weeks when refrigerated at 2–8 °C and protected from light. Stability varies by sequence — peptides containing cysteine, methionine, or tryptophan residues degrade faster and may require shorter usage windows in research protocols.

Published stability data for reconstituted peptides varies by amino acid composition, but the general laboratory guideline is 3–4 weeks at 2–8 °C (refrigerated) when reconstituted in bacteriostatic water and protected from light. The benzyl alcohol preservative addresses microbial contamination but not chemical degradation — oxidation, deamidation, and aggregation proceed independently. Peptides containing cysteine, methionine, or tryptophan residues are particularly oxidation-prone and show shorter reconstituted half-lives. For long-term storage, lyophilized powder at −20 °C in a desiccated environment remains the documented standard, with reconstitution performed as close to use as a protocol allows.

Source: Eur J Pharm Biopharm (2015) · PubMed

Bacteriostatic Water — 30mL, USP Grade purity →

Summarised from peer-reviewed literature for research reference. For laboratory research use only.