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

What are the steps to reconstitute a peptide?

Peptide reconstitution has seven steps: read the vial label, pick a BAC water volume that lands your dose at a readable unit count, disinfect the stopper with isopropyl, slowly add BAC water down the inside wall, swirl gently until dissolved (never shake), compute the draw volume in Peptly, and save the mix for one-tap reload. Math: vial mass ÷ BAC water = concentration.

What you need

• Lyophilized peptide vial
• Bacteriostatic water for injection (BWFI)
• U-100 insulin syringe (or a setting-compatible alternative)
• Isopropyl alcohol swabs
• Peptly iOS app for the math + log

Step-by-step

1. Read the vial label. Confirm the peptide name and the total mass in mg. Note the lot number and the manufacturer recommendations for reconstitution if present.

2. Pick a BAC water volume. Choose a bacteriostatic water volume so that your typical dose lands at a readable unit count on a U-100 syringe — usually 10–50 units. Peptly's slider shows the unit count live as you adjust BAC.

3. Disinfect the rubber stopper. Wipe the vial stopper with an isopropyl alcohol swab and let it dry for ~30 seconds before piercing.

4. Add BAC water slowly. Draw the chosen BAC water volume into a syringe and inject it into the vial slowly, angling the needle so the stream runs down the inside wall of the vial rather than hitting the powder directly.

5. Swirl gently. Roll the vial between your palms or swirl gently until the powder is fully dissolved. Do not shake. Most peptides dissolve in seconds; a few take longer.

6. Compute draw volume in Peptly. Open Peptly, select the peptide profile, set the vial mass and BAC water you just used, and pick the target dose. The app shows the exact U-100 units and the draw mark on a visual syringe.

7. Save the reconstitution mix. Save the mix (vial × BAC × concentration) in Peptly so future doses reload in one tap — no need to re-derive the math.

Common mistakes

• Shaking the vial. Swirl gently; do not shake.
• Adding too little or too much BAC water. Pick the volume so your dose lands at 10–50 units on a U-100 syringe.
• Mixing up mcg and mg. 1 mg = 1,000 mcg.
• Confusing U-100 and U-40. 10 units on U-100 is 0.1 ml; 10 units on U-40 is 0.25 ml.
• Re-deriving the math every dose. Save the mix in Peptly.

See also

• Peptide calculator
• BAC water calculator
• Reconstitution math reference
• Peptide dosage reference

Frequently asked questions

Should I shake the vial after adding BAC water? +

Most research protocols recommend gentle swirling or rolling rather than shaking. Vigorous shaking can damage some peptides. Swirl until the powder is fully dissolved.

What if the powder does not fully dissolve? +

Most peptides dissolve in seconds; some take longer. If powder remains after several minutes of gentle swirling, let the vial sit at room temperature for 5–10 minutes and swirl again. Do not heat.

Can I reuse a syringe between draws? +

No. Use a new sterile syringe for each draw. This is a standard injection hygiene rule, not a Peptly recommendation.

Where should reconstituted peptide be stored? +

Most research protocols refrigerate at 2–8 °C. Stability varies by peptide — most are typically used within 2–4 weeks. Consult primary sources or a licensed clinician.

How does Peptly help with reconstitution math? +

Peptly computes vial mass ÷ BAC water = concentration, and target dose ÷ concentration = draw volume (in units on a U-100 syringe). The visual syringe view shows the exact draw mark. Saved mixes reload in one tap.