Research Tool

Reconstitution & Dosing Calculator

Calculate exact injection volumes and syringe units for any peptide or blend. Select a peptide to pre-populate defaults from its research profile, or enter values manually.

For research and educational purposes only. This tool does not constitute medical advice. Always follow established laboratory safety protocols and applicable regulations.

How to Reconstitute a Peptide Vial

Lyophilized peptide powder must be dissolved in bacteriostatic water before injection. Follow these steps carefully to avoid degrading the peptide.

  1. 01
    Clean both vial tops with a fresh alcohol swab. Allow them to air-dry for 10–15 seconds before proceeding. This applies to both the peptide vial and the bacteriostatic water vial.
  2. 02
    Draw the measured volume of bacteriostatic water into an insulin syringe. Use the syringe units from the calculator above to draw the correct amount. Work on a clean, stable surface.
  3. 03
    Inject the water against the inner glass wall of the peptide vial — not directly onto the powder. This prevents foaming and mechanical degradation. Insert the needle at an angle so the liquid trickles down the side.
  4. 04
    Gently swirl the vial in a slow circular motion until the powder is fully dissolved. Do not shake, vortex, or agitate vigorously — peptide chains are fragile and can be disrupted by mechanical stress.
  5. 05
    Store the reconstituted vial refrigerated at 2–8°C (36–46°F). Most reconstituted peptides remain stable for 14–28 days under refrigeration. Label the vial with the date of reconstitution and the resulting concentration.

Frequently Asked Questions

Research-grade peptides are typically supplied as lyophilized (freeze-dried) powder because this form is more stable during storage and shipping than a liquid solution. Reconstitution is the process of dissolving that dry powder in a solvent — almost always bacteriostatic water (sterile water preserved with benzyl alcohol) — to produce an injectable solution at a known concentration.

The concentration is determined entirely by how much solvent you add relative to the mass of peptide in the vial. This calculator computes that relationship and translates it into injection volumes for your target dose.

The amount of water to add depends on the peptide's vial size and the dose range being studied. A common convention for 5 mg vials is 1–3 mL of bacteriostatic water, which yields concentrations of 1.67–5 mg/mL. Larger vials (10 mg) typically use 2 mL.

Selecting a peptide in this calculator will pre-populate the BAC water volume from that peptide's published reconstitution profile. You can override this value — the math will update in real time. The goal is to produce a concentration that results in a practical injection volume (typically 0.05–0.5 mL per dose).

The math is straightforward: Injection Volume (mL) = Dose (mg) ÷ Concentration (mg/mL). For example, if you reconstituted 5 mg in 1 mL of BAC water, your concentration is 5 mg/mL. A 1 mg dose requires 0.2 mL.

To convert that volume to syringe units, multiply by the units-per-mL of your syringe: U-100 syringes have 100 units per mL, so 0.2 mL = 20 units. U-50 syringes have 50 units/mL (0.2 mL = 10 units). This calculator performs all of this automatically and accounts for mcg-to-mg conversion.

Insulin syringes are calibrated in "units" that correspond to a specific volume per milliliter, originally standardized for insulin delivery. The number in the syringe type indicates how many units are marked per mL: U-100 (the most common type) marks 100 units per 1 mL, U-50 marks 50 units per mL, and U-40 marks 40 units per mL.

When calculating syringe units for a peptide dose, the only relevant quantity is the physical volume (mL) of solution to draw. The "units" marking is simply the scale on that syringe's barrel. This calculator converts mL to the appropriate unit marking for whichever syringe type you select.