Can I freeze reconstituted peptides to make them last longer

perfect. aliquoting into 5 vials this weekend.

Yes for most peptides, with caveats. Use sterile vials, aliquot before freezing, freeze deep (-20C home freezer is fine for weeks, not ideal for months). Avoid freeze-thaw cycles — thaw what you need, use it, don't refreeze. GHK-Cu and thymosins are less freeze-friendly; for BPC and most others it works.

Label everything with dates + contents. Mystery vials in the freezer 6 months later are a crisis waiting to happen.

Freezing works but the shelf life gain isn't huge. Studies show most reconstituted peptides degrade faster than lyophilized powder even when frozen, so you're looking at maybe 2-3 months before quality drops noticeably. If you're only using half a vial anyway, honestly just keep it in the fridge at 4C and use it in a month. Way simpler than dealing with aliquots and freeze cycles.