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Storage & stability

A peptide is only as good as its purity on the day you use it. Temperature, light, freeze-thaw cycles and transport all act on stability, and the right storage choice depends on whether the vial is dry or reconstituted.

Storage at a glance

How a vial should be stored depends on its state. The dry, lyophilised form is the most robust; once reconstituted, the clock starts.

StateTemperatureLightTypical stability
Lyophilised (dry)−20 °C freezerKeep darkMany months to years
Lyophilised (short term)2–8 °C fridgeKeep darkWeeks, for convenience
Reconstituted2–8 °C fridgeKeep darkDays to several weeks*
In transitCold-chain / cool packBoxedShort, by design

*Depends on the compound and on whether bacteriostatic or sterile water was used; always defer to the COA.

Do's and don'ts

Do

Keep dry vials in the freezer, store reconstituted vials in the fridge, keep everything dark, and return dry vials to the freezer promptly after they arrive.

Avoid

Don't freeze a reconstituted vial, don't leave anything in sunlight or warmth, and don't subject a solution to repeated freeze-thaw cycles.

Freeze-thaw, light & heat

Three stressors do most of the damage. Each has a simple countermeasure.

Freeze-thaw

Repeated freezing and thawing stresses the peptide bond. Keep a reconstituted solution in the fridge, not the freezer, so it is never cycled.

Light & heat

UV light and warmth both accelerate degradation. Keep vials dark and cool, a closed box in the fridge is ideal.

Brief warming

The dry, lyophilised form tolerates short warming in transit. It is the reconstituted solution that is sensitive, handle that one with more care.

Travel & cold-chain

Peptide.ST ships temperature-protected, so a vial arrives with its purity intact even after time in transit. The short warming a dry vial may see on the way is by design and well tolerated.

On arrival

Return dry vials to the freezer promptly when a shipment lands. For the full handling detail, see the Peptide.ST shipping policy.