Product details
Bacteriostatic Water for Injection (BAC Water) is sterile water containing 0.9% benzyl alcohol as a preservative, used as a multi-use reconstitution diluent. The benzyl-alcohol preservative inhibits microbial growth in a vial whose septum has been pierced repeatedly, supporting multi-dose use over the conventional ~28-day window after first puncture (the USP-compendial expectation for preserved injectable solutions). For preservative-compatible peptides it is the workhorse diluent in workflows where a single vial supports many small aliquots over a multi-week period. It is supplied as a characterized ancillary diluent rather than a research-target molecule.
Peptuno supplies BAC Water in sterile vial formats prepared from pharmaceutical-grade benzyl alcohol and Water for Injection, with the benzyl-alcohol content documented explicitly on the label and release packet alongside sterility and endotoxin data. BAC Water is not universally compatible: some short peptides interact with benzyl alcohol, and for those preservative-free Sterile Water for Injection in single-use aliquots is the recommended alternative. Confirm the recommended diluent for the specific peptide on its COA before defaulting to BAC Water.
Regulatory note: Reconstitution diluent containing benzyl-alcohol preservative; supplied for Research Use Only. Not universally compatible with all peptides — some require preservative-free SWFI. Verify sterility, endotoxin, and injectable-grade compliance with the destination market's requirements before use.
FAQ
- When should a lab use BAC Water versus preservative-free Sterile Water for Injection?
- Use BAC Water when the peptide is preservative-compatible and the workflow benefits from a multi-use vial — the 0.9% benzyl alcohol prevents microbial growth after multiple septum punctures, supporting many small aliquots over weeks. Use Sterile Water for Injection when the peptide is preservative-incompatible (some short peptides interact with benzyl alcohol), when the preparation is single-use within hours, or when the downstream work requires preservative-free chemistry. The recommended diluent per standard is noted on its COA.
- Is the ~28-day multi-use window a hard rule?
- It is the USP-compendial expectation for preserved injectable solutions and the conservative operational default, but actual stability depends on the specific peptide and storage conditions — some peptides warrant a shorter window, others tolerate longer. The 28-day default suits most reference-standard reconstitutions held refrigerated; stability for a specific peptide-in-diluent combination is an empirical question for the lab's own protocol.
- How is the benzyl-alcohol content documented?
- The benzyl-alcohol content is stated explicitly on the product label and the release packet, alongside sterility and endotoxin data, so a lab can confirm preservative compatibility for its peptide before use. Where a peptide is benzyl-alcohol-incompatible, the preservative-free SWFI diluent is the documented alternative.
Certificate of Analysis (COA)
The per-lot COA for this product will appear here.
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