Storing lyophilised powder
- Long term: -20°C or colder, sealed, protected from light and moisture
- Medium term: 2-8°C for a few weeks is generally acceptable
- Allow the vial to reach room temperature before opening to avoid condensation drawing moisture into the powder
- Keep the desiccant and original stopper intact
Reconstitution
Bacteriostatic water (sterile water with 0.9% benzyl alcohol) is the usual diluent because the preservative suppresses microbial growth in a multi-use vial. Add the diluent slowly down the inside wall of the vial rather than directly onto the powder.
Technique
- Swab the stopper with an alcohol wipe and let it dry
- Draw the calculated volume of bacteriostatic water into a sterile syringe
- Introduce it slowly against the glass wall, never as a jet onto the powder
- Roll or swirl gently until dissolved — never shake or vortex aggressively
- Label the vial with compound, concentration and reconstitution date
Storing solution
- Refrigerate reconstituted solution at 2-8°C and keep it dark
- Aliquot into single-use volumes before freezing to avoid repeat freeze-thaw
- Discard if the solution becomes cloudy, discoloured or shows particulate
- Treat the stability window on the product page as a maximum, not a target
Common mistakes
- Shaking the vial, which shears the peptide and causes aggregation
- Using tap or non-sterile water instead of bacteriostatic water
- Leaving powder at room temperature for weeks before use
- Freezing and thawing the same vial repeatedly
- Failing to label reconstitution dates, making stability impossible to audit