Bacteriostatic Water (0.9% Benzyl Alcohol)

Bacteriostatic Water for Injection (USP) is a sterile, non-pyrogenic preparation of water containing 0.9% (9 mg/mL) benzyl alcohol as a bacteriostatic preservative. The benzyl alcohol preservative inhibits bacterial growth in the vial, allowing multiple uses from a single multi-dose vial over an extended period — typically up to 28 days after initial puncture. Bacteriostatic water is the standard reconstitution solvent for lyophilised (freeze-dried) peptide and protein research compounds: lyophilised peptides are supplied as dry powder and must be dissolved in an appropriate solvent before use in laboratory research. The 0.9% benzyl alcohol concentration is sufficient to prevent microbial contamination of the reconstituted solution without interfering with peptide solubility or stability. The water is USP (United States Pharmacopeia) grade, ensuring sterility, non-pyrogenicity, and appropriate pH for reconstitution of sensitive peptide compounds. Bacteriostatic water is distinguished from sterile water for injection (which contains no preservative and is single-use only) by the presence of the benzyl alcohol preservative that enables multi-dose use.