Mobile phase,Standard preparation,Resolution solution,andChromatographic system— Proceed as directed in the Assayunder Cefmetazole.

Assay preparation 1(where it is represented as being in a single-dose container)— Constitute Cefmetazole for Injection in a volume of water,accurately measured,corresponding to the volume of solvent specified in the labeling.Withdraw all of the withdrawable contents,using a suitable hypodermic needle and syringe,and quantitatively dilute with Mobile phaseto obtain a solution containing about 0.2mg of cefmetazole per mL.[NOTE—Use this solution within 10minutes.]

Assay preparation 2(where the label states the quantity of cefmetazole in a given volume of constituted solution)— Constitute Cefmetazole for Injection in a volume of water,accurately measured,corresponding to the volume of solvent specified in the labeling.Quantitatively dilute an accurately measured volume of the constituted solution with Mobile phaseto obtain a solution containing about 0.2mg of cefmetazole per mL.[NOTE—Use this solution within 10minutes.]

Procedure— Proceed as directed in the Assayunder Cefmetazole.Calculate the quantity,in mg,of cefmetazole (C15H17N7O5S3)withdrawn from the container,or in the portion of constituted solution taken by the formula: in which Lis the labeled quantity,in mg,of cefmetazole in the container,or in the volume of constituted solution taken;Dis the concentration,in mg per mL,of cefmetazole (C15H17N7O5S3)per mL,of Assay preparation 1or Assay preparation 2,based on the labeled quantity in the container or in the portion of constituted solution taken,respectively;Cis the concentration,in µg per mL,of cefmetazole (C15H17N7O5S3)in the Standard preparation;and rUand rSare the cefmetazole peak responses obtained from the relevant Assay preparationand the Standard preparation,respectively.