Best Practices for Peptide Storage and Handling

Why Proper Storage Matters

Peptides are sensitive molecules that can degrade when exposed to heat, moisture, light, or oxygen. Proper storage is essential to maintain the purity and activity of your research compounds.

Following these guidelines will help ensure your peptides remain stable throughout your research project.

Storing Lyophilised (Freeze-Dried) Peptides

Lyophilised peptides are the most stable form for storage. Here’s how to keep them in optimal condition:

Temperature

• Short-term (weeks): Store at -20°C
• Long-term (months to years): Store at -80°C for maximum stability
• Avoid: Repeated freeze-thaw cycles

Protection from Moisture

Lyophilised peptides are hygroscopic—they readily absorb moisture from the air. To prevent this:

• Keep vials sealed until ready for use
• Allow vials to reach room temperature before opening (prevents condensation)
• Use desiccants in storage containers
• Work quickly when the vial is open

Light Protection

Many peptides are photosensitive. Store in:

• Original amber vials (if provided)
• Dark storage boxes or wrapped in foil
• Refrigerators/freezers away from fluorescent lighting

Reconstituting Peptides

When you’re ready to use your peptides, follow these reconstitution guidelines:

Choosing a Solvent

• Bacteriostatic water - Most common, suitable for most peptides
• Sterile water - For single-use applications
• Acetic acid (0.1%) - For basic peptides that are difficult to dissolve
• DMSO - For hydrophobic peptides (use minimal volume)

Reconstitution Process

1. Calculate the volume needed for your desired concentration
2. Add solvent slowly down the side of the vial
3. Gently swirl—never vortex or shake vigorously
4. Allow to dissolve completely (may take several minutes)
5. If cloudiness persists, a small amount of acetic acid may help

Storing Reconstituted Peptides

Once in solution, peptides are less stable than their lyophilised form:

Short-term Storage (Days to Weeks)

• Store at 2-8°C (refrigerator)
• Use within 2-4 weeks for most peptides
• Check for precipitation or cloudiness before each use

Long-term Storage (Weeks to Months)

• Aliquot into single-use portions to avoid freeze-thaw cycles
• Store aliquots at -20°C or -80°C
• Label clearly with date, concentration, and contents

Peptide-Specific Considerations

Some peptides require special handling:

GHK-Cu (Copper Peptide)

• Highly hygroscopic—extra care with moisture
• Solutions are typically blue due to copper content
• Stable in solution at 4°C for extended periods

Cysteine-Containing Peptides

• Prone to oxidation—minimise air exposure
• Consider adding reducing agents to solutions
• Use argon or nitrogen to displace air in vials

Large Peptides (>30 amino acids)

• More sensitive to aggregation
• May require specific buffer conditions
• Consider sterile filtration after reconstitution

Summary Table

Conclusion

Proper storage and handling of peptides is fundamental to successful research. By following these guidelines, you can ensure your peptides maintain their purity and activity throughout your experiments.

If you have questions about specific peptide storage requirements, our technical team is always available to help.