Glossary

Bacteriostatic Water

Reagent

Bacteriostatic Water — Sterile water containing 0.9% benzyl alcohol as a preservative, commonly used for reconstituting lyophilized peptides in research settings.

What Is Bacteriostatic Water?

Bacteriostatic water (BAC water) is sterile water containing 0.9% benzyl alcohol as a bacteriostatic preservative. It is the standard solvent for reconstituting lyophilized peptides in research settings because the benzyl alcohol inhibits microbial growth, allowing multi-use access over days to weeks without contamination.

Composition and Properties

Base: USP-grade sterile water for injection
Preservative: 0.9% (9 mg/mL) benzyl alcohol
pH: 4.5 to 7.0
Osmolality: Hypotonic
Sterility: Manufactured under aseptic conditions, typically in 10mL or 30mL multi-dose vials

Bacteriostatic vs. Sterile Water

Sterile water contains no preservative and is intended for single use only. Once opened, it has no protection against microbial contamination. Bacteriostatic water can be accessed multiple times over 28 days because the benzyl alcohol continuously suppresses bacterial growth. For multi-dose peptide vials, bacteriostatic water is the correct choice.

Research Considerations

Benzyl alcohol at 0.9% concentration does not interfere with most peptide activity assays. However, for sensitive cell culture experiments, benzyl alcohol may be cytotoxic at certain concentrations. In these cases, reconstitute with sterile water and use immediately or aliquot into single-use portions stored at -20°C.

Frequently Asked Questions

What is Bacteriostatic Water?

Sterile water containing 0.9% benzyl alcohol as a preservative, commonly used for reconstituting lyophilized peptides in research settings.

Why is Bacteriostatic Water important in peptide research?

Bacteriostatic Water is a fundamental concept in reagent as it relates to peptide science. It directly influences experimental design, compound characterization, and the reliability of research outcomes across biochemistry and molecular biology disciplines.

Authority Sources

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