Handling·· 5 min read
Reconstitution basics: choosing BAC water volume
The math behind converting a lyophilised vial into a workable stock solution — with a worked example on a 10 mg vial.
Reconstitution volume is not arbitrary. It sets the concentration of your stock, which in turn sets how many units you draw for a given target dose.
Concentration equation
Concentration (mg/mL) = Vial mass (mg) ÷ BAC water (mL)
A 10 mg vial reconstituted with 2 mL yields 5 mg/mL. A 2 mg target dose therefore requires 0.4 mL — 40 units on a U-100 insulin syringe.
Choosing volume
Smaller volumes give higher concentrations and lower draw volumes, but require more accurate syringes. Aim for a stock concentration that puts your typical daily dose between 10 and 40 units.
Stability
Once reconstituted, most peptides are stable refrigerated for 14–28 days. Freeze at –20°C for longer storage — but avoid repeated thaw cycles.