A perfect COA means nothing if the material degrades in the fridge. The unglamorous variables that decide whether a peptide survives.
Peptide integrity is decided long after purchase. Lyophilized (freeze-dried) peptide is relatively stable frozen, but once reconstituted the clock starts — and temperature, light, and the diluent all matter.
Bacteriostatic water is the common reconstitution medium for research handling because the benzyl alcohol suppresses microbial growth. Reconstituted peptide generally belongs refrigerated and used within a bounded window, not left at room temperature.
None of this is human-use guidance — it's basic sample-handling that determines whether the material in the vial still matches the COA it shipped with.
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