Reconstitution is one of the most overlooked steps in peptide research. Done correctly, it preserves potency and gives reproducible study data. Done badly, it introduces variability that can ruin months of work.
What you need
- A vial of lyophilised peptide (research-grade, ≥99% pure)
- Sterile bacteriostatic water (0.9% benzyl alcohol preserved)
- 1 ml insulin syringe with a fine 29G needle
- Alcohol prep pads
- A clean, dust-free work surface
The procedure
1. Bring the vial to room temperature. Cold vials cause condensation inside.
2. Wipe the rubber septum of both vials with an alcohol pad.
3. Draw the required volume of BAC water into the syringe.
4. Slowly inject the water against the inside glass wall of the peptide vial — do not hit the powder directly.
5. Allow the powder to dissolve passively. If it lingers, gently rotate the vial. Never shake — agitation degrades the peptide.
6. Label the vial with date of reconstitution and concentration.
Dilution math
Concentration (mg/ml) = vial dose ÷ BAC water volume.
Example: A 5 mg vial + 2 ml BAC = 2.5 mg/ml. A 0.1 ml draw = 0.25 mg.
Storage after reconstitution
Refrigerate at 2–8 °C immediately. Most peptides remain stable for 28–30 days post-reconstitution. For longer-term storage, aliquot and freeze at −20 °C in single-use volumes to avoid freeze-thaw cycles.
Common mistakes
- Using tap or distilled water instead of bacteriostatic water — drastically shortens shelf life.
- Shaking the vial — causes denaturation.
- Reusing syringes — introduces contamination.
- Skipping the alcohol wipe.
Take your time. A clean, slow reconstitution preserves the 99%+ purity you paid for.