What you need
- The lyophilised peptide vial
- Bacteriostatic water (0.9% benzyl alcohol — inhibits microbial growth in multi-use vials)
- Sterile insulin syringe for transfer
- Alcohol prep pads for the vial stoppers
The process
Swab both vial stoppers. Draw the chosen volume of bacteriostatic water and introduce it into the peptide vial slowly, down the glass wall — never jet it directly onto the powder, as mechanical stress can degrade fragile peptide chains. Let it dissolve on its own; gently swirl if needed, never shake.
Concentration table
Final concentration is simply mg of peptide ÷ mL of water added. For a 10mg vial:
| Water added | Resulting concentration |
|---|---|
| 1 mL | 10 mg/mL |
| 2 mL | 5 mg/mL |
| 3 mL | 3.33 mg/mL |
| 5 mL | 2 mg/mL |
More dilute solutions make small quantities easier to measure accurately; the right choice depends on the research design.
After reconstitution
Refrigerate at 2–8°C. Bacteriostatic water keeps multi-use vials usable for the standard research window (typically up to 4 weeks refrigerated); plain sterile water does not. Avoid freeze-thaw cycles and light exposure.