Reconstitution & Handling Guide

Bacteriostatic water is sterile water with 0.9% benzyl alcohol added as a preservative. That preservative is the whole point: it inhibits bacterial growth across multiple punctures of the same vial, which is what makes it suitable for reconstituting a vial you'll draw from more than once.

Plain sterile water or saline don't contain a preservative — once punctured, they should be treated as single-use, since there's nothing stopping contamination from building up over repeated draws. Saline's ionic content can also affect the solubility of some peptide sequences, particularly those with charged residues.

• Work on a clean, flat surface and wash your hands thoroughly before handling any vials.
• Take both the peptide vial and the bacteriostatic water vial out and remove their plastic caps.
• Wipe the rubber stopper on both vials with a fresh alcohol swab and let them air dry for a few seconds — don't blow on them or wipe them dry, which can reintroduce contaminants.
• Use your reconstitution calculator beforehand to know exactly how much water you're adding — deciding this after you've started increases the risk of a rushed, contaminated draw.

1. Draw the calculated volume of bacteriostatic water into a clean syringe.
2. Insert the needle into the peptide vial at a slight angle, aiming for the glass wall rather than straight down onto the powder. This lets the water run down the side and settle rather than blasting the powder directly, which can cause foaming.
3. Inject the water slowly and steadily.
4. Before withdrawing the needle, lift it so the tip sits above the liquid but is still under the rubber stopper, and let any pressure equalise naturally rather than pulling back hard on the plunger.
5. Swirl or gently roll the vial between your palms until the powder is fully dissolved. Never shake it — vigorous agitation can physically damage the peptide's structure.

• Refrigerate reconstituted solutions at 2–8°C — most peptides begin losing stability at room temperature over time.
• Keep vials away from direct light and heat. Some compounds are light-sensitive; a fridge door pocket is rarely ideal since it sees more light and temperature swings than the back of a shelf.
• Avoid freeze-thaw cycling. Freezing a reconstituted solution can damage the peptide's structure unless you have specific guidance stating otherwise for that compound.
• Typical stability once reconstituted is commonly cited around 3–4 weeks refrigerated, though this varies by compound — treat it as a general guide, not a fixed rule for every peptide in the catalogue.
• Unopened bacteriostatic water doesn't need refrigeration — room temperature, away from direct light and heat, is fine until it's punctured.

Once bacteriostatic water has passed its opened-shelf-life, or a reconstituted solution is past its stability window or showing signs of degradation, dispose of it responsibly rather than continuing to use it. Used needles, syringes, and vials should go into an appropriate sharps container and be disposed of according to your local regulations for biohazardous or clinical waste — not general household rubbish.