How to reconstitute peptides: a simple six-step guide

Peptides arrive as a dry powder in a small glass vial. To reconstitute a peptide means adding a liquid so the powder dissolves. Done carefully, you end up with a liquid and know how much peptide is in each mL.

When your vial arrives

• The powder can look like almost nothing. It might be a small white cake, loose powder or a thin film on the glass. A vial can even look empty. That's normal: a few milligrams is a tiny amount. See why vials can look nearly empty.
• It's fine that it arrived at room temperature. Dry powder is stable for the few days it spends in the post. See why peptides ship at room temperature.
• Keep it in the freezer until you're ready to mix it. Once it's mixed, it goes in the fridge (Step 6). A dry vial keeps much longer than a liquid one, so only mix it when you need it. See how to store peptides.

What you'll need

You'll need the vial and bacteriostatic water. Bacteriostatic water is sterile water with a little benzyl alcohol added, a preservative that slows the growth of bacteria. That helps because you'll open the vial more than once. See what bacteriostatic water is.

Step 1: choose how much liquid to add

Most of our vials hold 3 mL, so 2 mL of liquid is a good, common choice. It leaves room at the top and is easy to measure. NAD+ comes in a larger 10 mL vial.

The amount of liquid decides the concentration: how many milligrams (mg) of peptide are in each millilitre (mL). Less liquid makes it stronger, and more liquid makes it weaker. Choose your vial below to work it out:

Your vial

Choose the vial you boughtBPC-157 · 5 mgCJC-1295 (no DAC) · 5 mgEpitalon · 10 mgGHK-Cu · 50 mgIpamorelin · 5 mgKPV · 10 mgMOTS-c · 10 mgNAD+ · 500 mgRetatrutide · 10 mgSelank · 5 mgSemax · 5 mgSS-31 · 10 mgTB-500 · 5 mgTesamorelin · 10 mg

Peptide in the vial

mg

Filled in when you choose a vial, or type it from the label.

Liquid you add

mL

2 mL fits comfortably in a 3 mL vial.

Enter both numbers to see the concentration.

To do it by hand, divide the peptide in the vial (printed on its label) by the liquid you add. For example, a 5 mg vial with 2 mL added comes to 5 ÷ 2 = 2.5 mg/mL. The peptide calculator does more: it corrects for net peptide content, works in mM and plans aliquots.

Write the concentration and today's date on the vial's label, so you'll know later.

Step 2: let the vial warm up

Take the vial out of the freezer and leave it closed for 20 to 30 minutes, until it's at room temperature. If you start while it's cold, moisture from the air settles on the powder, like condensation on a cold glass (Bachem).

Step 3: bring the powder to the bottom

The powder is very fine and can cling to the glass and the stopper. Tap the vial gently on the bench a few times so the powder falls to the bottom. If you have a centrifuge, a spin of a few seconds does the same job.

Step 4: open the vial and add the liquid

1. Flip off the plastic top. Push it up with your thumb and it pops off.
2. Add the liquid slowly, letting it run down the inside of the glass rather than straight onto the powder. This stops the powder being blown about.

Step 5: swirl gently until clear

Swirl the vial gently in small circles, or roll it between your fingers. Don't shake it. Shaking makes bubbles and can make the peptide clump together. Most peptides dissolve within a few minutes, and some take 10 to 15 minutes.

When it looks done, hold the vial up against something dark:

Step 6: keep it in the fridge

• Store the vial upright in the fridge, at 2 to 8 °C, with the stopper in.
• Keep it away from light. The box it came in is fine.
• Don't freeze it once it's a liquid. Freezing and thawing breaks peptides down.

Once it's a liquid, a peptide breaks down much faster than it does as a powder (Bachem). In the fridge, that usually means days rather than weeks, and it varies from one peptide to another. That's why it's best to reconstitute a vial only when you need it. See how long peptides last.

Made a mistake?

Quick checklist

1. Keep the vial in the freezer until you need it.
2. Choose how much liquid to add (2 mL is common) and work out the concentration.
3. Let the closed vial warm to room temperature for 20 to 30 minutes.
4. Tap the powder down to the bottom.
5. Flip off the plastic top, then run the liquid slowly down the inside of the glass.
6. Swirl gently until clear, and don't shake.
7. Label it with the concentration and date, and keep it upright in the fridge.

Scope

This guide is for laboratory work. Our products are for research use only and are not for human or veterinary use. See Quality for how we test each batch.