Do Peptides Need to Be Refrigerated?
Yes — proper refrigeration is essential for maintaining peptide integrity. However, the specific storage requirements depend on whether your peptides are in lyophilized (freeze-dried) or reconstituted form.
Lyophilized Peptide Storage
Lyophilized peptides are the most stable form and offer the most storage flexibility: Short-term (weeks): Room temperature is acceptable for most lyophilized peptides, though not ideal. Medium-term (months): Refrigerate at 2-8°C for up to 6-12 months. Long-term (years): Freeze at -20°C for maximum shelf life of 2+ years.
Reconstituted Peptide Storage
Once mixed with bacteriostatic water, peptides MUST be refrigerated at 2-8°C. Reconstituted peptides left at room temperature will degrade within hours to days. Properly refrigerated reconstituted peptides maintain stability for approximately 3-4 weeks.
What Happens Without Refrigeration?
Peptides exposed to elevated temperatures undergo accelerated degradation through deamidation, oxidation, and hydrolysis. The higher the temperature and longer the exposure, the greater the potency loss. Even a few hours at high temperatures during shipping is generally acceptable for lyophilized peptides, but reconstituted solutions are much more sensitive.
Best Practices
Store in the back of the refrigerator (most stable temperature). Protect from light. Keep vials upright. Minimize temperature fluctuations from repeated door opening. For detailed storage protocols, see our complete storage guide.
Related Articles: Peptide Shelf Life | What Happens If Peptides Get Warm? | Can Peptides Expire?
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