UK stock · Same-day dispatch before 2pm
Bacteriostatic Water UK
Sterile bacteriostatic water for peptide reconstitution — water for injection with approximately 0.9% benzyl alcohol as a preservative, sealed in a multi-entry vial. Available in 3ml and 10ml, held in UK stock and dispatched the same working day on orders placed before 2pm. Supplied for laboratory research use only.
Checking live stock…
- Sterile, non-pyrogenic, sealed vials
- 0.9% benzyl alcohol preservative — multi-entry
- UK stock, Royal Mail Tracked 24
- Free 4 needles + 4 alcohol swabs with peptide orders
How much bacteriostatic water per peptide vial?
The volume you add sets the concentration, so it changes how many units you draw — not how much peptide you get. Use the table below as a starting point, then confirm exact figures with the free peptide calculator.
| Vial | Bac water | Concentration | 1mg dose |
|---|---|---|---|
| 5mg | 2ml | 2,500 mcg/ml | 40 iu |
| 10mg | 2ml | 5,000 mcg/ml | 20 iu |
| 10mg | 3ml | 3,333 mcg/ml | 30 iu |
| 20mg | 2ml | 10,000 mcg/ml | 10 iu |
| 30mg | 3ml | 10,000 mcg/ml | 10 iu |
| 40mg | 3ml | 13,333 mcg/ml | 7.5 iu |
Units shown for a 1ml / 100 unit insulin syringe.
Bacteriostatic water vs sterile water vs acetic acid water
| Diluent | Preservative | Use case |
|---|---|---|
| Bacteriostatic water | 0.9% benzyl alcohol | Default diluent for almost every research peptide; supports multi-entry vials |
| Sterile water for injection | None | Single-entry only — no preservative, so no protection after first puncture |
| Acetic acid water | None (dilute acid) | Only for AOD-9604, Ipamorelin and Tesamorelin — 0.5ml first, then top up with bac water |
Need the acidic diluent too? See Acetic Acid Water 3ml.
How to reconstitute with bacteriostatic water
- Choose your volume with the peptide calculator.
- Swab the stopper of both the bac water vial and the peptide vial.
- Draw the chosen volume of bacteriostatic water into a sterile syringe.
- Inject slowly down the inside wall of the vial — not straight onto the powder.
- Swirl gently until completely clear. Never shake.
- Refrigerate at 2–8°C, away from light, and avoid freeze-thaw cycles.
Full walkthrough in the peptide reconstitution guide.
Bacteriostatic water UK — FAQs
- What is bacteriostatic water?
- Bacteriostatic water is sterile water for injection containing approximately 0.9% benzyl alcohol as a preservative. The benzyl alcohol inhibits bacterial growth, which is what allows a reconstituted vial to be entered more than once under controlled laboratory conditions.
- Where can I buy bacteriostatic water in the UK?
- Peptides UK 4U holds bacteriostatic water in UK stock in 3ml vials at £3.49 and 10ml vials at £5.99, dispatched the same working day on orders placed before 2pm Monday to Friday.
- How much bacteriostatic water do I add to a peptide vial?
- There is no single correct volume — the amount you add sets the concentration. Common laboratory choices are 1ml, 2ml or 3ml per 10mg vial. Pick a volume that puts your target draw between roughly 5 and 40 units on an insulin syringe so it lands on a clear tick mark. Use the free peptide calculator to work out the exact figures.
- What is the difference between bacteriostatic water and sterile water?
- Sterile water for injection contains no preservative, so a vial reconstituted with it is single-entry only. Bacteriostatic water contains 0.9% benzyl alcohol, which suppresses bacterial growth and supports multi-entry use of the reconstituted vial within its stated window.
- Is bacteriostatic water the same as acetic acid water?
- No. Acetic acid water is a dilute acidic diluent used only for a small number of peptides that will not fully dissolve in bacteriostatic water — specifically AOD-9604, Ipamorelin and Tesamorelin. For those, add roughly 0.5ml of acetic acid water first, then top up with bacteriostatic water. For every other peptide in our range, bacteriostatic water alone is the correct diluent.
- How long does bacteriostatic water last once opened?
- Manufacturers typically state a 28-day window for an opened multi-dose bacteriostatic water vial when stored correctly. Unopened vials should be kept at room temperature, out of direct light, until use.
- How should I store a peptide reconstituted with bacteriostatic water?
- Refrigerate the reconstituted vial at 2–8°C, protect it from light, and avoid repeated freeze-thaw cycles. Swirl gently to mix — never shake, as agitation can damage the peptide chain.
- How much bacteriostatic water do I need per order?
- A 3ml vial covers a single 10mg peptide vial reconstituted at 3ml. A 10ml vial covers three to five peptide vials depending on your chosen concentration, and works out cheaper per ml if you are reconstituting more than one compound.
- Is bacteriostatic water legal to buy in the UK?
- Bacteriostatic water is legal to buy and hold in the UK for laboratory research purposes. It is supplied here strictly for in vitro research use only — not for human or animal use.
Add bacteriostatic water to your order
3ml from £3.49 or 10ml at £5.99 — UK stock, dispatched same day before 2pm.
Buy bacteriostatic waterFor in vitro research use only — not for human use. Not a medicine and not for consumption.