Peptide Reconstitution Calculator (Canada)

Last updated: July 2026  |  By the ThePeptide Research Team

This free peptide reconstitution calculator converts a lyophilized research peptide into a working concentration. Enter the amount of peptide in the vial, the volume of bacteriostatic water you are adding, and your target amount per measurement, and it returns the solution concentration and the corresponding mark on a standard insulin syringe. It is a measurement aid for laboratory research only.

Research Use Only This calculator is provided for laboratory and research measurement purposes only. Research peptides sold by ThePeptide are not approved by Health Canada or the FDA and are not for human or veterinary consumption. This tool performs arithmetic on values you enter; it is not medical, dosing, or administration advice.

Reconstitution Calculator

Quick presets: 10 mg / 2 mL10 mg / 1 mL5 mg / 2 mL5 mg / 1 mL
5 units
to measure 250 mcg · 50 mcg per unit
5 / 100 units
Visual is approximate and scaled to the selected syringe capacity.
5 mg/mL
Concentration
0.05 mL
Volume per draw
40
Draws per vial

How to Use This Calculator

  1. Peptide in vial (mg): the labelled mass of lyophilized peptide, e.g. a 10 mg vial.
  2. Bacteriostatic water (mL): the volume of solvent you add to reconstitute the powder. More water = a more dilute solution and more syringe units per unit of peptide.
  3. Target amount per draw: the mass you want each measurement to contain (in micrograms or milligrams).
  4. Syringe type: almost all research fluid handling uses U-100 insulin syringes, where 100 units = 1 mL.

The calculator updates instantly and shows the concentration, the fluid volume per draw, the corresponding number of insulin-syringe units, and how many draws the vial yields at that target amount.

How Peptide Reconstitution Works

Reconstitution is the process of dissolving a freeze-dried (lyophilized) peptide into a liquid so it can be measured accurately. The standard solvent is bacteriostatic water (0.9% benzyl alcohol), which resists microbial growth in multi-use vials. General laboratory technique for handling a research peptide is:

  1. Select the solvent volume and calculate the resulting concentration (use the tool above).
  2. Add the bacteriostatic water slowly down the inner wall of the vial rather than directly onto the powder.
  3. Swirl gently until fully dissolved — do not shake, as agitation can degrade fragile peptide chains.
  4. Store the reconstituted solution refrigerated and protected from light, per your laboratory protocols.

The Reconstitution Formula

The math behind the calculator is simple arithmetic:

Concentration (mg/mL) Peptide mass (mg) ÷ water volume (mL)
Volume per draw (mL) Target mass (mg) ÷ concentration (mg/mL)
Syringe units (U-100) Volume per draw (mL) × 100
Draws per vial Peptide mass (mg) ÷ target mass (mg)

Remember that 1 mg = 1000 mcg, and on a U-100 syringe 100 units = 1 mL, so 1 unit = 0.01 mL. These two conversions are all you need to move between mass, volume, and syringe marks.

Concentration & Units Reference Chart

Common reconstitution combinations, assuming a U-100 insulin syringe (100 units = 1 mL):

Vial + water Concentration Target amount Volume Units (U-100)
10 mg + 1 mL 10 mg/mL 500 mcg 0.05 mL 5 units
10 mg + 2 mL 5 mg/mL 250 mcg 0.05 mL 5 units
10 mg + 2 mL 5 mg/mL 500 mcg 0.10 mL 10 units
10 mg + 2 mL 5 mg/mL 1 mg 0.20 mL 20 units
5 mg + 2 mL 2.5 mg/mL 250 mcg 0.10 mL 10 units
5 mg + 1 mL 5 mg/mL 250 mcg 0.05 mL 5 units

Reference values for laboratory measurement only — not a recommendation of any amount for use in any organism.

What You Need to Reconstitute

Two supplies cover essentially every reconstitution: a solvent and a fine-gauge syringe for precise fluid measurement.

Frequently Asked Questions

How much bacteriostatic water should I add to a 10 mg peptide vial?

There is no single correct volume — it depends on the concentration you want. Adding 1 mL to a 10 mg vial gives 10 mg/mL; adding 2 mL gives 5 mg/mL. More water makes each syringe unit represent less peptide, which can improve measurement precision for small target amounts. Use the calculator above to model any combination.

How many units is 1 mg on an insulin syringe?

It depends entirely on concentration. On a U-100 syringe with a 5 mg/mL solution (10 mg in 2 mL), 1 mg equals 0.2 mL, or 20 units. With a 10 mg/mL solution (10 mg in 1 mL), 1 mg equals 0.1 mL, or 10 units. Enter your figures above to get the exact mark.

What does "units" mean on a U-100 insulin syringe?

A U-100 insulin syringe is graduated so that 100 units equals 1 mL, meaning 1 unit equals 0.01 mL. Units measure liquid volume, not peptide mass, so the same number of units contains different amounts of peptide depending on how concentrated your reconstituted solution is.

Can I use sterile water instead of bacteriostatic water?

Sterile water contains no preservative, so a reconstituted solution is best used quickly and stored cold. Bacteriostatic water contains 0.9% benzyl alcohol, which suppresses microbial growth and is the standard choice for multi-use research vials that will be accessed over several days.

Does more water change how much peptide is in each draw?

Adding more water does not change the total peptide in the vial — only its concentration. A larger solvent volume means each syringe unit carries less peptide, so you draw more units to measure the same mass. The calculator shows this trade-off instantly as you change the water volume.

How should I store a reconstituted peptide?

Reconstituted research peptide solutions are generally kept refrigerated and protected from light, and lyophilized powder is stored cool and dark before reconstitution. Always follow your laboratory's own stability and storage protocols for the specific compound and solvent in use.

Is this calculator giving me a dose to take?

No. This tool performs concentration and volume arithmetic on the numbers you enter, for laboratory measurement reference only. The peptides are research-use-only and are not approved by Health Canada or the FDA for human or veterinary use. Nothing here is medical or dosing advice.

Related Research Resources

References

  1. United States Pharmacopeia. Bacteriostatic Water for Injection — monograph and 0.9% benzyl alcohol preservative specification.
  2. Concentration and dilution arithmetic follows standard laboratory practice: concentration = mass ÷ volume; U-100 insulin syringe graduation of 100 units per millilitre.

Final Disclaimer — Research Use Only Research peptides supplied by ThePeptide are intended exclusively for in-vitro laboratory and research purposes. They are not approved by Health Canada or the FDA, are not drugs or dietary supplements, and are not for human or veterinary consumption or clinical use. This calculator is a measurement aid only and does not constitute medical advice, a dose, or an administration instruction. Users are responsible for compliant handling and use.
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