Peptide Storage Guide: Temperature, Moisture, and Shelf Life
Comprehensive storage guidelines for research peptides covering lyophilized powder, reconstituted solutions, freeze-thaw cycles, and degradation signs.
Introduction
Proper peptide storage is critical for maintaining biological activity and research reproducibility. This guide covers optimal conditions for both lyophilized and reconstituted peptides.
Lyophilized (Powder) Storage
| Temperature | Shelf Life | Recommendation |
|---|---|---|
| -20C (freezer) | 2-5 years | Best for long-term |
| 4C (refrigerator) | 6-12 months | Short-term storage |
| Room temperature | Days only | Transport only |
Key Rules
- Store in sealed vials with desiccant
- Protect from light (amber vials preferred)
- Avoid temperature fluctuations
- Keep vials sealed until use
Reconstituted (Liquid) Storage
| Temperature | Shelf Life | Notes |
|---|---|---|
| -80C | 6-12 months | Aliquot before freezing |
| -20C | 2-3 months | Avoid repeated freeze-thaw |
| 4C | 2-4 weeks | Most peptides |
| Room temp | Hours only | Use immediately |
Solvent Choice
- Bacteriostatic water: General purpose (0.9% benzyl alcohol preservative)
- Sterile water: Short-term only (no preservative)
- Acetic acid (0.1-1%): For acidic peptides
- DMSO: For hydrophobic peptides (then dilute with buffer)
Freeze-Thaw Damage
Each freeze-thaw cycle degrades peptides by 5-10%. To minimise damage:
- Aliquot into single-use volumes before freezing
- Thaw on ice, not at room temperature
- Never refreeze a thawed aliquot
- Label aliquots with date and concentration
Signs of Peptide Degradation
| Sign | Cause | Action |
|---|---|---|
| Cloudy solution | Aggregation/precipitation | Discard |
| Yellow/brown colour | Oxidation | Discard |
| Reduced solubility | Hydrolysis | Discard |
| pH change | Degradation | Check with pH paper |
Peptide-Specific Storage
| Peptide | Special Storage Notes |
|---|---|
| BPC-157 | Stable, standard storage |
| GHK-Cu | Light-sensitive, store in dark |
| CJC-1295 | Sensitive to moisture, keep desiccated |
| Melanotan II | Light and heat sensitive |
| Semax/Selank | Store at -20C when reconstituted |
Frequently Asked Questions
Can I store peptides at room temperature?
Lyophilized peptides can survive short periods (days) at room temperature during shipping. For any period longer than a few days, refrigerate or freeze.
How long do reconstituted peptides last?
Most peptides are stable for 2-4 weeks at 4C (refrigerator) when reconstituted with bacteriostatic water.
Conclusion
Proper storage preserves peptide integrity and ensures research accuracy. Follow these guidelines to maximise shelf life and biological activity.