Research use only. The information below concerns laboratory reference materials for in-vitro research and makes no medical, therapeutic, diagnostic, cosmetic or performance claims.
Preparing an in-vitro stock solution from a lyophilised reference material requires unit-aware arithmetic and values for the exact material and lot. This guide covers the calculations; our laboratory stock-concentration & aliquot calculator performs them automatically.
Stock concentration
For the added-volume convention, divide the reference-material mass by the volume of solvent added. A 5 mg reference with 2 mL of solvent added gives a nominal stock concentration of 2.5 mg/mL. This convention does not account for solute-volume displacement.
Aliquot volume
To calculate an aliquot volume for a target mass, divide the target mass by the stock concentration. At 2.5 mg/mL, a 250 µg aliquot is 0.10 mL (100 µL).
Net peptide content
Use the lot-specific net peptide content from the COA when available, rather than assuming the gross vial mass is entirely peptide. Water, counterion and other reported components can affect the relationship between supplied mass and peptide amount.
Storage and prepared-solution stability
Storage and reconstitution conditions are specific to the material, formulation, solvent, concentration and container. Follow the exact lot documentation and a validated laboratory procedure; do not infer prepared-solution stability from storage conditions for the lyophilised material. These calculations are for in-vitro laboratory planning only.