Mobile phase, Standard preparation, Resolution solution, and Chromatographic system— Proceed as directed in the Assay under 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 phase to obtain a solution containing about 0.2 mg of cefmetazole per mL. [note—Use this solution within 10 minutes.]

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 phase to obtain a solution containing about 0.2 mg of cefmetazole per mL. [note—Use this solution within 10 minutes.]

Procedure— Proceed as directed in the Assay under 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 Calculate the quantity, in mg, of cefmetazole (C15H17N7O5S3) withdrawn from the container, or in the portion of constituted solution taken by the formula: in which L is the labeled quantity, in mg, of cefmetazole in the container, or in the volume of constituted solution taken; D is the concentration, in mg per mL, of cefmetazole (C15H17N7O5S3) per mL, of Assay preparation 1 or Assay preparation 2, based on the labeled quantity in the container or in the portion of constituted solution taken, respectively; C is the concentration, in µg per mL, of cefmetazole (C15H17N7O5S3) in the Standard preparation; and rU and rS are the cefmetazole peak responses obtained from the relevant Assay preparation and the Standard preparation, respectively.