Bacteriostatic Water (BAC Water) is one of the most important tools in peptide research. While peptides arrive as a white, lyophilized (freeze-dried) powder, they must be reconstituted into liquid form before use in experiments. BAC water provides a safe, sterile, and longer-lasting way to prepare peptides for research.
What is BAC Water?
Bacteriostatic Water is sterile water for injection that contains a small amount of benzyl alcohol (0.9%). The benzyl alcohol prevents bacterial growth, allowing the water to be used multiple times from the same vial without contamination. This makes it different from plain sterile water, which must be discarded immediately after opening.
Why Researchers Use BAC Water
- Extends shelf life: Peptides reconstituted with BAC water can often be kept refrigerated for 20–30 days without issue.
- Multi-use vials: Allows researchers to withdraw small amounts repeatedly using sterile technique, without discarding the vial after first puncture.
- Cost effective: Reduces waste compared to single-use sterile water ampules.
BAC Water vs. Sterile Water
| Sterile Water | Bacteriostatic Water |
|---|---|
| Sterile, no preservatives | Sterile + 0.9% benzyl alcohol |
| Single-use only (discard after opening) | Multi-use (up to 28 days after first puncture) |
| Good for sensitive applications where preservatives are not wanted | Best choice for peptide reconstitution in research |
Storage & Shelf Life
- Unopened BAC water vials: store at room temperature in a clean environment.
- After opening: refrigerate and use within 28 days.
- Always use sterile needles/syringes to withdraw fluid and avoid contaminating the vial.
Frequently Asked Questions
Can I use sterile water instead of BAC water? - Yes, but it must be used all at once. BAC water is recommended when multiple reconstitutions or repeated withdrawals will be made from the same vial.
Why does BAC water have benzyl alcohol? - The 0.9% benzyl alcohol acts as a preservative to stop bacterial growth. This small amount is enough to keep the solution safe for repeated use.
Does BAC water change peptide activity? - No, BAC water is the standard solvent for research peptide reconstitution. It does not alter peptide structure when stored properly at cold temperatures.
Explore More
• Bacteriostatic Water - Product Page
• How to Reconstitute Peptides - Step by Step Guide
• Medical Supplies Collection
Disclaimer: For laboratory research use only. Not for human consumption, therapeutic, or diagnostic use. Follow local laws and regulations.
