Peptide Storage & Reconstitution Guide | Bio Mech Research

2–8°C for short-term archive; −20°C for long-term. Keep vials upright, dry and away from light.

Refrigerated, capped, with the reconstitution date and concentration written on the vial. Discard at the end of the COA's in-use window.

Every vial should carry the compound, concentration, reconstitution date and lot number. Internal SOPs should govern transfer to working stocks.

Lyophilised powder is stable precisely because it is dry; the moment it absorbs atmospheric moisture, both degradation chemistry and measurement problems begin. Hygroscopic sequences can take on water visibly — a formerly free-flowing cake that turns glassy or clumped has already absorbed enough to matter. Water content also affects net peptide mass: a 5 mg vial with 3% residual water contains marginally less peptide than the nominal figure, which the certificate reports as a measured value.

Practical controls follow directly: keep vials in a sealed container with desiccant rather than loose in a door shelf, limit the time an opened vial spends outside cold storage, and let cold vials come to room temperature before opening — condensation on a cold vial is the most common way moisture enters an otherwise correct routine.

A recurring question is whether international transit at ambient temperature damages lyophilised peptides. For properly lyophilised material, short transit periods are within the stability envelope — the powder is engineered to survive exactly this kind of journey, which is why suppliers do not need to ship dry ice for standard orders. What matters is what happens on arrival: transfer to 2–8°C promptly, check the physical state of the cake, and reconcile the batch number against the certificate.

Sustained heat is a different case. A parcel left in a hot vehicle or a sunlit letterbox for days is outside the design envelope, and a degraded cake — discoloured, clumped or visibly wet — should be photographed and raised with the supplier rather than used. Check the physical condition of every vial on arrival before moving it into storage.

The most common storage failure in practice is not the archive — it is the working stock. A stock solution that lives in a shared fridge door, unlabelled, past its in-use window, quietly contaminates every downstream measurement. The disciplines that prevent it are simple: every working stock carries a label with compound, batch, concentration and preparation date; aliquots are single-use rather than repeatedly drawn; and a fixed discard date is written on the vial rather than remembered.

For laboratories with several users, a single-page SOP attached to the fridge — covering who may open which box, labelling format, and discard rules — resolves most of the ambiguity that otherwise turns into error.