Assay preparation
Dilute an accurately measured volume of solution of Penicillin G Potassium for Oral Solution, constituted as directed in the labeling, quantitatively and stepwise with
Buffer No. 1 (see
Media and Diluents under
AntibioticsMicrobial Assay 81) to obtain a solution containing about 2000 Penicillin G Units per mL. Pipet 2 mL of this solution into each of two glass-stoppered, 125-mL conical flasks.
Procedure
Proceed as directed for
Procedure under
Iodometric AssayAntibiotics 425. Calculate the quantity, in Penicillin G Units, in each mL of the constituted solution of Penicillin G Potassium for Oral Solution taken by the formula:
(
L / 2
D)(
F)(
B I),
in which
L is the labeled quantity, in Penicillin G Units per mL in the constituted solution of Penicillin G Potassium for Oral Solution, and
D is the concentration, in Units per mL, of Penicillin G in the
Assay preparation on the basis of the labeled quantity in the constituted solution of Penicillin G Potassium for Oral Solution and the extent of dilution.