A: The chromatogram of the Assay preparationobtained as directed in the Assayexhibits a major peak for cefuroxime,the retention time of which corresponds to that exhibited in the chromatogram of the Standard preparationobtained as directed in the Assay.

B: It responds to the tests for Sodium á191ñ.

pH3.4acetate buffer— Transfer 50mLof 0.1Msodium acetate to a 1000-mLvolumetric flask,dilute with 0.1Nacetic acid to volume,and mix.

Mobile phase— Prepare a suitable mixture of pH3.4acetate bufferand acetonitrile (about 10:1).Filter through a membrane filter (1µm or finer porosity),and degas.

Internal standard solution— Prepare a solution of orcinol in water containing 1.5mg per mL.

Standard preparation— Dissolve a suitable quantity of USP Cefuroxime Sodium RS,accurately weighed,in water to obtain a solution having a known concentration of about 1mg of cefuroxime (C16H16N4O8S)per mL.Immediately transfer 5.0mLof the resulting solution to a 100-mLvolumetric flask,add 20.0mLof Internal standard solution,dilute with water to volume,and mix.This Standard preparationcontains about 0.05mg of cefuroxime per mL.

Assay preparation— Using a suitable quantity of Cefuroxime Sodium,accurately weighed,proceed as directed in the first sentence under Standard preparation.Immediately transfer 5.0mLof the resulting solution to a 100-mLvolumetric flask,add 20.0mLof Internal standard solution,dilute with water to volume,and mix.

Chromatographic system (see Chromatography á621ñ)—The liquid chromatograph is equipped with a 254-nm detector and a 4.6-mm ×15-cm column that contains 5-µm packing L15.The flow rate is about 2mLper minute.Chromatograph the Standard preparation,and record the peak responses as directed under Procedure:the column efficiency determined from the analyte peak is not less than 1300theoretical plates,the tailing factor for the analyte peak is not more than 2.0,the resolution,R,between the analyte and internal standard peaks is not less than 3.5,and the relative standard deviation for replicate injections is not more than 2.0%.

Procedure— Separately inject equal volumes (about 10µL)of the Standard preparationand the Assay preparationinto the chromatograph,record the chromatograms,and measure the responses for the major peaks.The relative retention times are about 0.5for cefuroxime and 1.0for orcinol.Calculate the quantity,in µg,of cefuroxime per mg of the Cefuroxime Sodium taken by the formula: in which Cis the concentration,in mg of cefuroxime (C16H16N4O8S)per mL,in the Standard preparation;Mis the concentration,in mg per mL,in the Assay preparationbased on the weight of Cefuroxime Sodium taken and the extent of dilution;and RUand RSare the peak response ratios of the cefuroxime peak to the internal standard peak obtained from the Assay preparationand the Standard preparation,respectively.