Every compound page states a storage temperature, a light-sensitivity note where it applies, and a shelf life. These aren't boilerplate. They reflect real chemistry about how a dry, freeze-dried solid breaks down over time, and each one is worth understanding on its own.
Temperature
Freeze-dried peptides are generally stored frozen (around -20 degrees C) for long-term storage, with short-term storage in a refrigerator (2 to 8 degrees C) usually fine for the periods stated on the compound page. Cold storage slows down the small chemical reactions that can still happen, at a much slower rate, even in a dry solid. Freezing and thawing a vial over and over is generally worse for it than steady storage at one temperature, which is one reason a stable storage spot matters more than any single reading.
Light sensitivity
Some compounds are specifically sensitive to light: their storage line says so, and we package them in an amber (light-blocking) vial and box for that reason. Light, especially certain wavelengths, can break down some molecules faster than others, depending on their structure. Keeping a light-sensitive compound in its original packaging, not just at the right temperature, is part of following its stated handling.
Moisture
A freeze-dried cake can reabsorb moisture from the air if left unsealed, which brings back the same water-related breakdown that freeze-drying was meant to prevent in the first place. See lyophilization, why peptides ship as powder. Keeping the vial sealed until use, and resealing it promptly afterward, protects against this.
Shelf life
The shelf life on each compound page is measured from the lot's release date, under the storage conditions also stated there. It depends on how the material is stored, not just on the compound itself: material kept consistently at the right temperature, away from light and moisture as directed, is expected to stay within spec for the stated period. Material stored inconsistently has no such guarantee, no matter what the label says.
What storage guidance does not cover
Storage and handling information describes how to keep freeze-dried material stable before any laboratory use. It does not cover anything after that point. This site does not provide that guidance, in any form.
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