Made in USA · ≥99% HPLC
Sterile Diluent
Bacteriostatic Water for Peptide Reconstitution – 3 mL & 10 mL
0.9% benzyl alcoholLaboratory diluent3 mL · 10 mL
Sterile water with 0.9% benzyl alcohol as a bacteriostatic preservative, supplied in 3 mL and 10 mL sealed vials as a laboratory diluent for dissolving lyophilized research compounds.
Price range: $14.95 through $19.95
In stock
For laboratory and research use only. Not for human consumption.
This product is not a drug, food or cosmetic. It is sold exclusively to qualified researchers and licensed laboratories.
Tested by Freedom Diagnostics TestingHPLC purity + LC-MS identityLot-matched COA on-site
Arrives in 3–5 days
Free shipment protection
Secure encrypted payment
US-sourcedSterile-filled & lab-released in the United States
Independent COAThird-party Certificate of Analysis per lot
Sterility + endotoxinReleased against sterility and endotoxin testing
Same-day dispatchOrders before 2 PM CT ship the same business day
What is Bacteriostatic Water?
Bacteriostatic Water is sterile water with 0.9% benzyl alcohol as a bacteriostatic preservative, supplied as a laboratory diluent for dissolving lyophilized research compounds. Store sealed; handle per your lab SOP once opened.
Plain sterile water contains no preservative. Bacteriostatic water’s pH (4.5–7.0) is compatible with most research peptides, though it is not suitable for compounds known to be incompatible with benzyl alcohol — plain sterile water should be used for those. Koi supplies bacteriostatic water for laboratory use only.
Every lot, independently verified
Independently third-party tested and matched to the lot ID printed on your vial. Values below are from the latest released lot.
0.9%
Benzyl alcohol
Passed full QC panel
Independent third-party lab (Freedom Diagnostics Testing)
View COA (PDF)
Sterile water + 0.9% benzyl alcohol · laboratory diluent
Lot details
ProductBacteriostatic Water
CompositionSterile water + 0.9% benzyl alcohol
Volumes3 mL · 10 mL
GradeSterile
UseLaboratory diluent
Full QC panel · third-party lab5 assays
SterilityNo Growth ✓
Endotoxin (USP <85>)Within limits ✓
Benzyl alcohol0.9% ✓
pH4.5–7.0 ✓
AppearanceClear, colorless ✓
Bacteriostatic water is released against sterility and endotoxin testing by an independent third-party laboratory (Freedom Diagnostics Testing). The lot-specific certificate is published in our public COA library and matched to the lot ID printed on the vial.
Browse full COA library →
Product information
Composition & handling reference data — specifications, composition and storage.
Product Specifications
ProductBacteriostatic Water (laboratory diluent)
Volumes3 mL & 10 mL
GradeSterile
PreservativeBenzyl alcohol (0.9%)
FormClear, colorless solution
pH4.5–7.0
Molecular weightN/A – diluent
Sterile-filledUnited States
Quality testingIndependent third-party laboratory release (Freedom Diagnostics Testing)
Composition
BaseSterile water
PreservativeBenzyl alcohol (0.9%)
FunctionBacteriostatic laboratory diluent
CompatibilityLyophilized research peptides
pH range4.5–7.0
UseDissolving lyophilized research compounds
Storage & Handling
AppearanceClear, colorless solution
CompositionSterile water + 0.9% benzyl alcohol
StorageRoom temperature, sealed · protect from light
Once openedHandle per your lab SOP
How Bacteriostatic Water Is Used
- Provides a sterile, preserved aqueous diluent for dissolving lyophilized research compounds.
- The 0.9% benzyl alcohol acts as a bacteriostatic preservative, inhibiting bacterial growth in the diluent.
- Its pH (4.5–7.0) is compatible with the majority of research peptides.
- Add the diluent slowly down the vial wall onto the lyophilized cake to limit foaming, and avoid vortexing.
- Not suitable for compounds that are incompatible with benzyl alcohol — use plain sterile water for those.
- Supports consistent solution preparation across an experimental series.
Bacteriostatic vs Sterile Water
- Plain sterile water contains no preservative.
- Bacteriostatic water contains 0.9% benzyl alcohol, which inhibits bacterial growth in the diluent.
- Preparation of stock solutions for cell-culture and biochemical assays.
- General laboratory use where benzyl alcohol compatibility is acceptable.
Why Buy Bacteriostatic Water from Koi Peptides?
- Every lot of Koi bacteriostatic water is sterile-filled in the United States and released against independent third-party laboratory (Freedom Diagnostics Testing) testing.
- Each lot is released against sterility and endotoxin testing, with the 0.9% benzyl alcohol content and pH confirmed.
- The lot ID is printed on every vial and ties back to a public COA library, so researchers can verify documentation before they buy and after the vial arrives.
- Orders placed before 2 PM CT ship the same business day, and shipping is free on orders over $200.
References
Handling references for laboratory use of bacteriostatic water.
Lab Handling Guide
Preparing solutions of lyophilized peptides
View all references +
- Koi Peptides. Preparing solutions of lyophilized peptides — laboratory handling guide. koipeptides.com/methodology/
Regulatory Status
Regulatory status — provided for research context.
Regulatory Status
Regulatory status — provided for research context.
Research Use
Koi supplies bacteriostatic water as a laboratory diluent for research use only. It is not a drug, food or cosmetic, and is not for human or veterinary use.
Disclaimer
For laboratory and research use only. Not for human consumption. This product is not a drug, food or cosmetic. It is sold exclusively to qualified researchers and licensed laboratories. These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.
Frequently Asked Questions About Bacteriostatic Water
What is bacteriostatic water used for?+
Bacteriostatic water (sterile water with 0.9% benzyl alcohol) is a laboratory diluent for dissolving lyophilized research compounds.
How is it different from sterile water?+
Plain sterile water contains no preservative. Bacteriostatic water contains 0.9% benzyl alcohol, which inhibits bacterial growth in the diluent.
How do I dissolve a peptide with it?+
Add the diluent slowly down the inner vial wall onto the lyophilized cake to limit foaming; do not vortex. Swirl gently until dissolved, then store the solution at 2–8 °C per your lab SOP.
What is the composition and pH?+
Sterile water with 0.9% benzyl alcohol as a bacteriostatic preservative, with a pH of 4.5–7.0 — compatible with most research peptides.
Which volume should I choose?+
The 3 mL vial suits smaller volumes; the 10 mL vial is more economical for higher-throughput laboratory work. Both contain sterile water with 0.9% benzyl alcohol.
How should it be stored?+
Store sealed at room temperature, protected from light. Handle per your lab SOP once opened.
Is it for human use?+
No. Bacteriostatic water is for laboratory and research use only and is not for human consumption. It is sold exclusively to qualified researchers and licensed laboratories.
Does it come with a Certificate of Analysis?+
Yes. The lot-specific Certificate of Analysis is published in our public COA library and matched to the lot ID printed on the vial, covering sterility, endotoxin, benzyl alcohol content, pH, and appearance from an independent third-party laboratory (Freedom Diagnostics Testing).
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