How to Reconstitute Research Peptides

What you'll need

• Your lyophilized peptide vial
• A reconstitution solvent — typically bacteriostatic water or acetic acid solution (see our BAC water vs. acetic acid guide)
• A sterile syringe
• Alcohol prep swabs
• A clean, draft-free work surface

Step 1 — Decide your concentration

Concentration is just mass ÷ volume. If you reconstitute a 10 mg vial with 2 mL of solvent, your solution is 5 mg/mL. Choose the solvent volume that gives the concentration your protocol calls for, and write it down.

Step 2 — Prep both vials

Swab the rubber stopper of the peptide vial and the solvent vial with alcohol and let them dry. This is the single most important step for avoiding contamination.

Step 3 — Draw your solvent

Draw the calculated volume of solvent into the syringe.

Step 4 — Add slowly, down the wall

Insert the needle and let the solvent run slowly down the inside wall of the vial — never blast it directly onto the powder. The peptide is delicate; a gentle stream protects it.

Step 5 — Dissolve gently

Swirl, don't shake. Let the vial sit and gently rotate it until the powder fully dissolves into a clear solution. Shaking introduces foam and shear stress that can damage peptide chains.

Common mistakes to avoid

• Shaking the vial — always swirl
• Spraying solvent onto the powder — run it down the wall
• Skipping the alcohol swab — contamination risk
• Wrong solvent — some peptides dissolve better in acetic acid

After reconstitution

Store the reconstituted solution refrigerated and away from light, and avoid repeated freeze-thaw cycles. See our peptide storage guide for specifics.