Reconstituting lyophilised peptides is one of the most fundamental laboratory procedures in peptide research. Getting it right ensures accurate dosing in experimental protocols and preserves the structural integrity of the compound.
What Does Reconstitution Mean?
Reconstitution is the process of dissolving a lyophilised (freeze-dried) peptide powder back into a liquid solution using a sterile solvent. Most research peptides arrive as a dry powder — this form is far more stable for shipping and long-term storage.
The two most common solvents are bacteriostatic water (BAC water) and sterile water. BAC water contains 0.9% benzyl alcohol as a preservative, making it preferred for multi-use vials.
Equipment You Will Need
- Lyophilised peptide vial
- Bacteriostatic water
- Insulin syringe (typically 1 mL / 100 units)
- Alcohol swabs for sterilising vial tops
Step-by-Step Reconstitution Process
- Clean the vial tops — Swab the rubber stopper on both the peptide vial and BAC water vial with an alcohol wipe. Allow to air dry.
- Draw the solvent — Using an insulin syringe, draw the desired amount of bacteriostatic water.
- Add water slowly — Insert the needle and release water gently down the inside wall of the vial. Do not squirt directly onto the powder.
- Gently swirl — Roll or swirl the vial between your fingers. Never shake — aggressive agitation can denature the peptide.
- Allow to dissolve — Most peptides dissolve within a few minutes. If particles remain, refrigerate for 15-30 minutes and swirl again.
Calculating Concentration
Concentration (mcg/mL) = (Peptide mg × 1000) ÷ Water mL
A 5 mg vial with 2 mL BAC water = 2,500 mcg/mL concentration.
Use our peptide dosage calculator to determine exact volumes for any dose.
Storage After Reconstitution
Store reconstituted solutions at 2-8°C. With BAC water, most peptides remain stable for 4-6 weeks. Sterile water solutions should be used within 48 hours or frozen in single-use aliquots.
Common Mistakes to Avoid
- Shaking the vial — Breaks peptide bonds and can render the compound inactive
- Non-sterile solvents — Always use pharmaceutical-grade BAC water
- Room temperature storage — Heat degrades peptides rapidly
- Reusing syringes — Always use a fresh, sterile syringe
Browse our full range of research accessories including bacteriostatic water, peptide pens, and needle tips.
This article is for educational and informational purposes only. All peptides sold by Regen Peptides are strictly for in-vitro research and laboratory use. Not for human consumption.
