Peptide reconstitution calculator
Enter the mass of lyophilized peptide in the vial and the volume of solvent added. The calculator returns the concentration of the prepared research solution and the volume needed to measure a target quantity for laboratory work.
How the calculation works
Concentration is the peptide mass divided by the solvent volume. A 5 mg vial reconstituted with 2 mL of bacteriostatic water gives 2.5 mg/mL, which is the same as 2,500 mcg/mL. Reconstitution is a standard laboratory sample-preparation step; the resulting concentration is a property of the vial's contents.
Draw volume for a target quantity is the target divided by the concentration. To measure 250 mcg from a 2,500 mcg/mL solution you would draw 0.1 mL, which reads as 10 units on a U-100 insulin syringe (100 units = 1 mL). These figures describe measurement of the research solution in the laboratory, not administration.
Frequently asked questions
How do you calculate reconstitution concentration? Divide the vial's peptide mass (mg) by the solvent volume (mL). 5 mg in 2 mL = 2.5 mg/mL (2,500 mcg/mL).
What solvent is used? In research settings, bacteriostatic water is common because its ~0.9% benzyl alcohol preservative allows multiple withdrawals from one vial.
How do insulin-syringe units convert to millilitres? On a U-100 syringe, 100 units = 1 mL, so 10 units = 0.1 mL.