How to Reconstitute Peptides
Reconstitution means mixing your lyophilized (freeze-dried) peptide powder with a solvent so you can inject it. Here's exactly how.
What You Need
- Your lyophilized peptide vial
- Bacteriostatic water (BAC water) or acetic acid — see comparison below
- A 3mL syringe with an 18G drawing needle
- Alcohol swabs
- A clean, flat surface
Choosing Your Solvent
The solvent you use depends on the peptide. Most peptides dissolve in BAC water, but some require acetic acid. Here's the full comparison:
| Solvent | Preservative | Multi-Use? | Shelf Life | Best For |
|---|---|---|---|---|
| Bacteriostatic Water (BAC) | 0.9% benzyl alcohol | Yes | 28 days after opening | Most peptides (BPC-157, TB-500, CJC-1295, etc.) |
| Sterile Water | None | No | 24 hours after opening | Single-use scenarios, allergies to benzyl alcohol |
| Acetic Acid (0.6%) | None (acidic pH inhibits bacteria) | No | 28 days reconstituted | IGF-1 LR3, IGF-1 DES, MGF (Mechano Growth Factor) |
Bacteriostatic Water (BAC): Gold standard for reconstitution. The preservative allows multiple draws from the same vial.
Sterile Water: No preservative means bacteria can grow. Use immediately or discard.
Acetic Acid (0.6%): Only required for the IGF-1 family and MGF — these peptides need a low-pH environment to remain stable. Most peptides are designed for neutral pH and should use BAC water instead.
Step-by-Step Reconstitution
- Wash your hands thoroughly with soap and water. Put on nitrile gloves if you have them.
- Swab the vial tops — clean the rubber stopper on both the peptide vial and the solvent vial with separate alcohol swabs. Let them air dry for a few seconds.
- Draw the solvent — using a 3mL syringe with an 18G needle, draw the desired amount of BAC water (commonly 1–2mL). Pull back on the plunger slowly to avoid bubbles.
- Inject into the peptide vial — insert the needle into the peptide vial and aim the stream at the glass wall, not directly onto the powder. Release the solvent slowly. The liquid should trickle down the side of the vial.
- Let it dissolve — the peptide may dissolve immediately or take a few minutes. Gently swirl the vial if needed. Never shake — shaking can damage the peptide.
- Inspect — the solution should be clear and free of particles. If it's cloudy or has visible chunks, continue swirling gently.
- Store immediately — place the reconstituted vial in the refrigerator at 36–46°F (2–8°C).
Video Guides
Reconstituting with BAC Water
Coming SoonReconstituting with Acetic Acid
Coming SoonCommon Mistakes to Avoid
- Squirting solvent directly onto the powder — always aim at the glass wall to avoid damaging the peptide
- Shaking the vial — this can denature the peptide. Swirl gently instead
- Using too little solvent — makes dosing inaccurate. Follow the calculator on peptide.locker
- Skipping alcohol swabs — bacteria from the vial top can contaminate the solution
- Leaving reconstituted peptides at room temperature — always refrigerate immediately after mixing