The conversion factors for a WHO biological reference preparation can be estimated once certain information is known.
NOTE: This is a generic extension for the handling of insulin in 40.38.01
Requirements:
(1) stated number of International Unit (IU) per mg in standard
(2) percent pure (100% minus salts, water and stabilizers)
(3) molecular weight of the compound
number of IU per mg if pure =
= (stated number of IU per mg) / (percent pure)
1 mole of the compound in IU =
= (molecular weight in grams) * (1000 mg per gram) * (number of IU per mg if pure)
1 IU in moles =
= 1 / ((molecular weight in grams) * (1000 mg per gram) * (number of IU per mg if pure))
