How to Reconstitute Peptides: A Step-by-Step Guide

Reconstitution is simply adding bacteriostatic water to a lyophilized (freeze-dried) peptide so it can be accurately measured. Getting the math right before you dose is the single most important step.

What you need

• Your lyophilized peptide vial
• Bacteriostatic water
• A sterile syringe to draw the water
• U-100 insulin syringes for measuring
• Alcohol swabs

Step by step

1. Swab both vial stoppers with alcohol and let dry.
2. Draw your chosen volume of bacteriostatic water with a sterile syringe.
3. Inject it slowly down the inside wall of the peptide vial — never blast it directly onto the powder.
4. Gently swirl or roll the vial until fully dissolved. Do not shake.
5. Label with the date and the concentration.
6. Refrigerate, protected from light.

After reconstitution

Store refrigerated at 2–8 °C and use within the window indicated for your compound. Avoid repeated freeze–thaw cycles.

The 10 mg rule

A common simplicity rule is 1 mL of bacteriostatic water per 10 mg of peptide, which gives a clean 10 mg/mL concentration. Use our dosage calculator to work out your exact units on a U-100 syringe.

For laboratory and scientific research use only. Not for human or animal consumption. This article is educational and is not medical advice. Always follow your own research plan.