Bacteriostatic water in Australia — reconstitution guide

Sterile water for injection contains no preservative. Once the stopper is pierced, the contents are treated as single use, because nothing in the solution suppresses microbial growth.

Bacteriostatic water contains 0.9% benzyl alcohol, which inhibits the growth of common bacteria. That is what makes a multi-draw vial workable, and it is the reason it is the default diluent in peptide reconstitution protocols.

Neither is a substitute for aseptic technique. Swab the stopper, use a fresh sterile syringe for every draw, and never return solution to the vial.

The volume you add sets the concentration; it does not change the amount of peptide in the vial. Adding 2mL to a 5mg vial gives 2.5mg per mL; adding 1mL to the same vial gives 5mg per mL.

Most labs pick a round volume so the arithmetic stays simple and the measurement lines on an insulin syringe map cleanly onto the intended sample size.

Add the water slowly down the inside wall of the vial rather than directly onto the powder cake, then swirl gently. Shaking shears the peptide chain and can reduce assayable content.

Reconstituted vials are refrigerated at 2-8°C, kept out of direct light, and not repeatedly frozen and thawed.

Label the vial with the reconstitution date, the volume added, and the lot number so concentration and age stay traceable alongside your results.

Unopened bacteriostatic water is stored at room temperature and inspected for particulates or cloudiness before use.

A reconstitution setup is typically bacteriostatic water, sterile insulin syringes for accurate small-volume measurement, and alcohol prep swabs for the vial stoppers.

We supply all three so a single cold-chain parcel arrives with everything needed to work with the vials, rather than leaving you to source consumables separately.

Materials on this site are supplied strictly for in-vitro laboratory research. They are not therapeutic goods, are not approved by the TGA for human use, and are not supplied for human or veterinary consumption.

Purchasers must be 18 or over and are responsible for handling, storing and disposing of research materials in line with their institution's requirements and applicable Australian law.

Nothing on this page is medical advice, a dosing protocol, or a claim of therapeutic benefit. It summarises what the published research literature investigates.