Lido BioScience

Free Tool

Peptide Reconstitution Calculator

Enter your vial size, the volume of bacteriostatic water you plan to add, and your target dose. The calculator returns concentration, micrograms per syringe unit, and the exact number of units to draw on a U-100 insulin syringe.

Result

Concentration

5.00 mg/mL

5000 mcg/mL

Per syringe unit

50.0 mcg

0.010 mL

Draw this many units

5.0 units

on a U-100 insulin syringe

Volume per dose

0.050 mL

for 250 mcg

A worked example. A 10 mg vial reconstituted with 2 mL of bacteriostatic water gives 5 mg/mL, or 5,000 mcg/mL. On a U-100 insulin syringe (100 units per mL), each unit is 0.01 mL of solution, which contains 50 mcg of peptide. A 250 mcg dose is therefore 5 units on the syringe.

This calculator does the same math for any vial size, water volume, and syringe scale you enter. Save the page and reuse it for any compound.

The math behind the calculator

Concentration is mass divided by volume. A 10 mg vial reconstituted with 1 mL of bacteriostatic water gives 10 mg/mL. The same vial with 2 mL of water gives 5 mg/mL. Choose volume based on how precise your dosing needs to be: more water means each syringe mark represents a smaller amount of peptide, which is useful for low microgram-range doses.

A U-100 insulin syringe is graduated in 100 units per mL. Each unit is therefore 0.01 mL. To convert a desired microgram dose into syringe units, divide your dose by the micrograms-per-unit number above the result.

A worked example end to end

You have a 10 mg vial of BPC-157 and want to dose 250 mcg per injection.

  1. Add 2 mL of bacteriostatic water to the vial. Tilt and inject slowly down the inside wall to avoid foaming.
  2. Swirl gently. The peptide should dissolve within a minute or two.
  3. Concentration is now 5 mg/mL, or 5,000 mcg/mL.
  4. On a U-100 insulin syringe, each unit is 0.01 mL, which contains 50 mcg of peptide.
  5. 250 mcg divided by 50 mcg per unit = 5 units.

Draw to the 5-unit mark on the syringe. Done.

A few practical notes

  • Bacteriostatic water (sterile water with 0.9 percent benzyl alcohol) is the standard choice. The preservative keeps the reconstituted vial stable for two to four weeks in the refrigerator. Sterile water without preservative is acceptable only for single-use reconstitutions.
  • Avoid foaming. Squirt the water gently down the side of the vial, then swirl. Shaking creates an air-water interface that can break peptide bonds.
  • Store reconstituted vials upright in the refrigerator (2 to 8 C), away from light. Discard if cloudy or discolored.
  • For sub-microgram precision, use more water (3 to 5 mL per vial), which spreads each microgram across more syringe units.

Lido BioScience supplies research peptides. Compounds listed in our catalog are not for human consumption and the information above is published as background reading on standard research protocols, not as medical guidance. If you are considering peptide use in any clinical context, talk to a physician.

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