Understanding reconstitution
A clear laboratory reference explaining concentration, diluent volume, and how reconstitution calculations work.
What reconstitution means
Lyophilised material is supplied as a dry cake sealed under vacuum. Reconstitution is the laboratory step of returning that solid to solution by introducing a measured volume of sterile diluent — typically bacteriostatic water — into the sealed vial.
The mass of material in the vial does not change. Only the volume of solution changes, and with it the resulting concentration.
The calculation
Concentration is a ratio of mass to volume: total material in milligrams divided by the total volume of solution in millilitres.
Total material (mg) ÷ total solution volume (mL) = concentration (mg/mL)
A 10 mg vial brought to 2 mL yields 5 mg/mL. The same vial brought to 1 mL yields 10 mg/mL. Less diluent means a more concentrated solution; more diluent means a more dilute one.
Diluent volume selection
Diluent volume is a laboratory handling decision driven by the precision of the measurement equipment in use and the working concentration required by the protocol. Larger volumes make small measured fractions easier to resolve accurately; smaller volumes conserve space and reduce total solution held in cold storage.
Handling practice
Diluent is introduced slowly against the inside wall of the vial, never directly onto the cake. The vial is swirled gently until fully dissolved — never shaken, as agitation can denature peptide material and generate foam.
Allow the solution to clear before use. Cloudiness, visible particulates or discolouration indicate the material should not be used.
Dosing calculator
Use the interactive calculator to convert vial strength and diluent volume into concentration and 100-unit insulin syringe units.
Laboratory reference only. Seven Saints products are intended for research use and are not intended to diagnose, treat, cure, or prevent disease or for human consumption.