Temperature speeds up almost every degradation reaction: as a rule of thumb, each rise of about 10 °C multiplies their rate. That is why how a peptide should be kept depends on its state. Freeze-dried, well sealed and protected from moisture, it reasonably tolerates short periods at room temperature, such as shipping, and cold is recommended for long-term storage. Reconstituted, by contrast, it must be kept refrigerated (2-8 °C) continuously.
Freezing is not always better. A peptide solution that is frozen and thawed repeatedly undergoes cryoconcentration and pH shifts that promote aggregation. If it is frozen, it is best done in single-use aliquots.
Light and moisture complete the equation: vials should be stored in their box, away from direct light, and freeze-dried material should not be exposed to humid air when opened cold, because water condenses on the powder.
A good share of “product that does not work” problems are explained by improper storage after receipt, not by the original quality. The cold chain is a shared responsibility.
Related terms
Learn it in depth at the Peptide University
- Stability and storage · Module 9
- Physical degradation: aggregation and adsorption · Module 11
- Lyophilization and excipients · Module 11
Definition for educational and scientific purposes. It is not medical advice or a recommendation for use. NeoPeptidos products are sold labelled for research use only (RUO).