Accessories
Bacteriostatic Water
10ml
Sterile water with 0.9% benzyl alcohol. For peptide reconstitution.
Sterile · Batch UKPL-818
- Same-day dispatch before 3pm, Mon to Fri
- Add £61.51 more for free UK delivery
- Cold-chain shipping. Always. Dry-cold pack, Royal Mail Tracked 24
- Lost, damaged or wrong? Replaced free if you tell us within 48 hours.
- Research use only. For in-vitro laboratory research. Not for use in humans or animals, or in food, drugs or diagnostics. Not evaluated by the MHRA or FDA. The buyer is responsible for handling and regulatory compliance.
What is Bacteriostatic Water?
Bacteriostatic water, or bac water, is sterile water with 0.9% benzyl alcohol as a preservative. It is the standard diluent for reconstituting lyophilised research peptides. Each vial holds 10ml.
Full description
The benzyl alcohol, 9mg per ml or 90mg per vial, holds back microbial growth between withdrawals. That lets one vial serve several reconstitutions within its in-use period. Benzyl alcohol and phenol are the two most common preservatives in licensed peptide and protein products (Meyer et al., J Pharm Sci, 2007).
Bacteriostatic Water Research Applications
Any lab working with lyophilised peptides needs a diluent to bring them into solution before in-vitro work. One 10ml vial covers several reconstitutions, for example of BPC-157, TB-500, MOTS-C, ipamorelin or DSIP.
Bacteriostatic Water vs Sterile Water for Injection
Sterile water for injection has no preservative. Once its seal is broken, nothing holds back organisms carried in on a needle, so it is a single-use diluent. Bacteriostatic water adds 0.9% benzyl alcohol, so one vial can be entered repeatedly for 28 days after first puncture. Choose sterile water when the preservative must be kept out of a design. Meyer and colleagues (2007) list a preservative's effect on the active ingredient among the main criteria for choosing one.
Research Overview
Mattner and Gastmeier (Am J Infect Control, 2004) collected every opened multiple-dose vial in a 1300-bed hospital on one day and tested each for sterility. Of 227 vials, one vial and one spike were contaminated, a rate of 0.9%. Only half the vials had their opening date marked, and 13% of those were already past it. 109 vials held medicines with no preservative at all.
Their recommendations included alcohol hand hygiene, marking the opening time and not reusing preservative-free vials. The same habits apply to a lab stock of bacteriostatic water. The benzyl alcohol limits growth from small numbers of organisms, but it does not replace aseptic technique.
Product Specifications
- Composition
- Sterile water with 0.9% (9mg/ml) benzyl alcohol
- Preservative
- Benzyl alcohol, bacteriostatic
- Volume
- 10ml
- Purity
- Sterile
- Batch
- UKPL-818
- Appearance
- Clear, colourless solution
- Storage
- 20-25°C, away from direct light, do not freeze
- In-Use Period
- Date at first puncture, discard after 28 days
- Form
- Ready-to-use solution, no reconstitution required
Storage and Handling
Store unopened vials at 20-25°C, away from direct light. Do not freeze. Write the date on the vial at first puncture and discard it 28 days later, or at the printed expiry if that comes first. Discard any vial that is cloudy, has particles or has a damaged seal.
How to handle
Bacteriostatic water needs no preparation. Swab the stopper with alcohol and let it dry before each entry. Add it slowly down the inside wall of the peptide vial, not onto the powder, and swirl gently until dissolved.
- Use a fresh sterile needle and syringe for every withdrawal, and never return liquid to the vial.
To mix a peptide, see the peptide reconstitution guide and the reconstitution calculator.
Research References
Bacteriostatic Water Price (UK)
Bacteriostatic Water 10ml is for sale at £7.49 per vial, supplied from stock in the UK. UK delivery is £4.50 by Royal Mail Tracked 24, free over £69.
| Vial | Price | Availability |
|---|---|---|
| Bacteriostatic Water 10mlThis page | £7.49 | In stock |
Prices are in GBP per vial of ready-to-use solution and match the basket. See the FAQ for delivery and payment options, and quality & testing for how each batch is checked.
Frequently Asked Questions
What is the difference between bacteriostatic water and sterile water?
The preservative. Bacteriostatic water contains 0.9% benzyl alcohol and sterile water contains none. Without a preservative, sterile water suits a single withdrawal. Bacteriostatic water can be entered repeatedly for 28 days after first puncture.
How long does bacteriostatic water last once opened?
28 days from first puncture, or the printed expiry if that comes sooner. Write the date on the label when you first pierce the stopper.
Why is bac water used to reconstitute peptides?
Because one vial can serve many reconstitutions. Lyophilised peptides have to be dissolved before in-vitro work, and the benzyl alcohol holds back organisms introduced by repeated needle entries. Benzyl alcohol is also one of the two most common preservatives in licensed peptide and protein products (Meyer et al., 2007).
Does bacteriostatic water sterilise a contaminated vial?
No. Benzyl alcohol is bacteriostatic: it stops small numbers of organisms from multiplying, but it does not kill an established population. Discard any vial that looks cloudy or whose seal is in doubt.
How should bacteriostatic water be stored?
At room temperature, 20-25°C, away from direct light. It does not need a fridge.
How much benzyl alcohol is in a 10ml bacteriostatic water vial?
90mg. At 0.9%, each ml holds 9mg of benzyl alcohol, so a 10ml vial holds 90mg in total.
Can bacteriostatic water be frozen?
No. Keep it at 20-25°C. If a vial has frozen by accident, check the seal and clarity before use, and discard it if in doubt.
Where can I buy bacteriostatic water in the UK?
UK Peptide Lab sells bacteriostatic water in 10ml vials from UK stock, so it can go in the same order as your peptides. Orders placed before 3pm (UK time) on a working day are dispatched the same day, and UK delivery is free over £69.
Is bacteriostatic water UK legal to buy for research?
Yes, for laboratory research. We sell it for research use only, to buyers aged 18 or over. It is not supplied as a medicine.
What size are your bac water vials and how long do they last?
Each vial holds 10ml. Unopened, use it before the printed expiry. Once pierced, discard it 28 days after first puncture.
Related Products
