How to Store Research Peptides: Powder vs Reconstituted
Storage makes or breaks peptide stability. A research guide to handling lyophilised vials and reconstituted solutions, and how long each one lasts.
Why Storage Matters
A peptide can arrive at high purity and still degrade quickly if it is stored badly. Temperature, light, and moisture all affect stability, and the rules differ depending on whether the peptide is still a powder or has been reconstituted.
Lyophilised (Powder) Storage
In its freeze-dried form, a peptide is remarkably stable.
- Short term: A sealed lyophilised vial is stable at room temperature for a period, provided it is kept cool and dry and out of direct light.
- Long term: For extended storage, refrigeration (2 to 8 C) or freezing is preferred. Frozen lyophilised peptides can remain stable for many months.
- Keep vials in their packaging, away from windows and heat sources.
Reconstituted (Liquid) Storage
Once mixed with bacteriostatic water, the clock speeds up.
- A reconstituted vial should be refrigerated at all times.
- The benzyl alcohol in bacteriostatic water inhibits bacterial growth, which is why it is the preferred diluent for multi-use vials.
- Avoid repeated temperature swings — do not leave the vial out and return it to the fridge over and over.
Quick Reference
| State | Storage | Approx. stability |
|---|---|---|
| --- | --- | --- |
| Lyophilised powder | Cool, dry, dark | Weeks at room temp |
| Lyophilised powder | Refrigerated or frozen | Many months |
| Reconstituted liquid | Refrigerated | Weeks |
A Note on Quality
Storage protects quality that was there to begin with. Every Peptides & You product starts with a third-party Certificate of Analysis confirming identity and purity — you can review them at peptidesandyou.com/lab-results. For mixing technique, see our reconstitution guide.
For laboratory and research use only. Not for human or veterinary consumption. These statements have not been evaluated by the U.S. FDA or the Philippine FDA.