How to store peptides depends on their state: the powder (lyophilisate) is robust and likes it dry, cool and dark; a reconstituted (mixed) solution belongs in the fridge and only keeps for a limited time. Keep the two cases apart - the rules differ.

Storing powder (lyophilisate) - how long does it last?

The freeze-dried powder (technical term: lyophilisate) is very stable but strongly water-attracting (hygroscopic). Store it airtight with a desiccant, protected from light. In the fridge (2–8 °C), well sealed and dry, the powder usually stays stable for several months up to about a year (depending on the peptide); for longer storage it belongs in the freezer (−18 °C or colder), where it often stays stable for years. How to freeze it properly is shown in the freezing guide.

Storing a reconstituted (mixed) solution

Once you have reconstituted (mixed) with BAC water, store the vial in the fridge at 2–8 °C, in the dark, and usually use the solution within about 21–30 days. Do not keep it in the fridge door (temperature swings). Details on BAC water and shelf life are in the FAQ.

A reconstituted (mixed) solution must never go in the freezer: ice crystals and freeze-thaw cycles can destroy the peptide. Freezing is only for the powder - see freezing.

Which peptides are how sensitive is shown in the peptide overview.

Note: Educational information, not medical advice. Many of these substances are experimental and not approved for human use.

Step by step

Step 1

Dry and airtight

Powder (lyophilisate) is hygroscopic. Keep it in an airtight container with a desiccant sachet so no moisture gets in.

Step 2

Cool and dark

Protect it from light and heat and store the vial upright. In the fridge (2–8 °C) the well-sealed, dry powder usually keeps for several months up to about a year. Pick a spot with stable 2–8 °C: not right at the back (it can freeze there) and not in the door (temperature swings when opened).

Peptides are light-sensitive - opaque insulin/medication cooler cases protect from light and keep things tidy; they are cheap on online marketplaces (e.g. a search for "vial case" on AliExpress).

Step 3

Freeze powder for the long term

For long-term storage the powder belongs in the freezer (−18 °C or colder) - it often stays stable for years. See the freezing guide.

Step 4

Reconstituted goes in the fridge

Store the reconstituted solution upright at a stable 2–8 °C, dark. Same rule: not right at the back (risk of freezing) and not in the door (temperature swings when opened).

Step 5

Mind the use-by window

Use a reconstituted solution within about 21–30 days. Label it with the date to keep track.

Or use our Dosage Manager: when logged in you can record the mix date, amount and usage per vial.

Storing peptides: powder vs. reconstituted solution