What does "lyophilized" mean?

Lyophilized means freeze-dried. A lyophilized peptide ships as a dry powder with the water removed, so all you see in the vial is a small white plug or film. Before you can use it, you add water back in — a step called reconstitution. That's the entire concept: it comes dry, you mix it.

Why peptides are freeze-dried

A peptide dissolved in water is fragile. It can degrade, and anything that grows in the liquid ruins it. Take the water away and almost none of that can happen.

Freeze-drying does exactly that: the material is frozen, then put under vacuum so the ice turns straight to vapor, leaving a dry, stable powder behind. The result is a vial that:

• survives shipping without a cold pack,
• stores for a long time, and
• stays chemically intact until you're ready to use it.

This is why every vial we ship at pepuro is lyophilized. It's also why a warm parcel isn't a problem — the storage guide covers that in more detail.

What you actually get

A lyophilized peptide is a two-part setup:

1. The dry peptide — the freeze-dried powder in the sealed vial.
2. The water — bacteriostatic water you add to dissolve it (supplied separately).

The powder on its own does nothing until you combine the two. Don't be alarmed if the plug looks tiny — a few milligrams of peptide doesn't take up much space.

The one step before use: reconstitution

Reconstitution just means adding the water back. Done gently, it takes a couple of minutes and preserves the purity of the material:

• Run the water down the glass wall of the vial, not straight onto the powder.
• Swirl, never shake.
• Let it sit if a little powder remains.

The full method, including how to work out the concentration, is in how to reconstitute a lyophilized peptide. Once it's mixed, the storage rules change — reconstituted peptide goes in the fridge and gets used within weeks.

Lyophilized vs. reconstituted at a glance

The short version

• Lyophilized = freeze-dried = dry powder.
• It arrives in two parts: the peptide and the water you add.
• You reconstitute it before use, then keep it cold.

You'll see "lyophilized" on every product in our catalog — including bestsellers like BPC-157 and TB-500 (how the two differ) — because that's how research peptides are meant to ship. The same applies to multi-peptide blends: two or more peptides freeze-dried into a single vial.

For research use only. Not for human or animal consumption.