Peptide Storage Guide
Complete storage guidelines for lyophilized and reconstituted research peptides — temperature requirements, shelf life, freeze-thaw rules, and light protection.
The Core Rule: Lyophilized vs. Reconstituted
Peptide storage requirements change dramatically depending on whether the vial is still sealed (lyophilized) or has been reconstituted (dissolved in liquid). These two states have completely different temperature and duration requirements.
| State | Temperature | Duration | Key Restriction |
|---|---|---|---|
| Lyophilized (sealed, dry) | −20°C (−4°F) preferred | 12–24 months | Keep dry; avoid moisture |
| Lyophilized (short-term) | 2–8°C (refrigerator) | Up to 3–6 months | Do not open; keep sealed |
| Reconstituted (in solution) | 2–8°C (refrigerator) | 14–30 days (peptide-dependent) | Never freeze after reconstitution |
Lyophilized Storage
Sealed lyophilized vials are highly stable. The freeze-drying process removes virtually all moisture, dramatically extending stability. Key rules:
- Freezer (−20°C) is ideal for long-term storage — typically 1–2 years from manufacture date.
- Refrigerator (2–8°C) works for shorter periods — acceptable for 3–6 months depending on the peptide.
- Room temperature is NOT acceptable for extended storage, even for sealed vials.
- Moisture is the enemy. Keep lyophilized vials in airtight containers. Silica gel desiccant packets help in humid environments.
- Allow vials to reach room temperature before opening — this prevents condensation from entering the vial when the stopper is punctured.
- Protect from light. Store in opaque containers or foil-wrapped.
Freezer tip: If storing in a freezer, consider keeping vials in a sealed bag or container with a desiccant packet to prevent frost accumulation and moisture exposure when the freezer is opened repeatedly.
Reconstituted Storage
Once reconstituted, the rules change completely. Peptides in solution are far more fragile:
- Refrigerate at 2–8°C immediately after reconstituting. Do not leave at room temperature.
- Never freeze reconstituted peptide solutions. Ice crystal formation during freezing physically damages peptide tertiary structures. Freeze-thaw cycles degrade potency rapidly.
- Use within the recommended window — typically 14–30 days depending on the peptide. Check the individual protocol pages for specific guidance.
- Swab the stopper with alcohol before every needle insertion. Bacteriostatic water prevents bacterial growth, but proper aseptic technique maintains sterility.
- Keep protected from light — store in the refrigerator's back, away from the door light.
Peptide-Specific Storage Windows (After Reconstitution)
| Peptide / Category | Reconstituted Shelf Life | Notes |
|---|---|---|
| BPC-157 | Up to 28 days | Avoid freeze-thaw; refrigerate immediately |
| TB-500 | Up to 28 days | Do not freeze reconstituted solution |
| GHK-Cu | Up to 30 days | Keep protected from light |
| Semaglutide | Up to 28 days | Same as approved product guidance |
| Tirzepatide | Up to 28 days | Avoid freeze-thaw |
| Retatrutide | Up to 4 weeks | Can aliquot and freeze aliquots ONCE |
| GHRPs / CJC-1295 No DAC | Up to 28 days | Keep refrigerated |
| Ipamorelin | Up to 28 days | Avoid light; refrigerate |
| Epitalon | Prepare fresh per cycle | Short 10–20 day cycles; use entire vial per cycle |
| HCG | 30–60 days | More stable with BAC water than sterile water |
| FOXO4-DRI | Use within current cycle | Prepare fresh; highly experimental |
Signs a Peptide May Have Degraded
- Reconstituted solution appears cloudy or has floating particles (clear should be normal)
- Solution has changed color from clear to yellow, brown, or any other color
- Unusual smell from the reconstituted solution
- Powder did not dissolve despite extended gentle swirling
- Vial was exposed to significant temperature extremes or was left unrefriegerated for extended periods
If any of these signs are present, do not use the compound. Discard appropriately and use a fresh vial.