A: Place a Tablet in a mixture of acetone and 0.1Nhydrochloric acid (4:1)of sufficient volume to obtain a solution containing 2.5mg of cefprozil per mL,shake for 5minutes,and allow the mixture to settle.Proceed as directed for Identificationtest Aunder Cefprozil for Oral Suspension,beginning with “Use the supernatant as the Test solution.”The specified result is obtained.

B: The retention times of the cefprozil (Z)-isomer and cefprozil (E)-isomer peaks in the chromatogram of the Assay preparationcorrespond to those of the Standard preparationsas obtained in the Assay.

Medium: water;900mL.

Apparatus 1: 100rpm.

Time: 45minutes.

Procedure— Determine the amount of cefprozil (C18H19N3O5S)dissolved in the Dissolution Medium,as directed in the Assay,using instead of the Assay preparationa filtered portion of the Dissolution Medium,diluted if necessary,to obtain a test solution containing about 0.3mg of cefprozil per mL.Calculate the quantity,in mg,of cefprozil (Z)-isomer and cefprozil (E)-isomer dissolved by the formula: in which Dis 1or,where the filtered Dissolution Mediumwas diluted to prepare the test solution,the appropriate dilution factor,and the other terms are as defined therein.Calculate the quantity,in mg,of cefprozil (C18H19N3O5S)dissolved by adding the quantity,in mg,of the cefprozil (Z)-isomer and cefprozil (E)-isomer dissolved.

Tolerances— Not less than 75%(Q)of the labeled amount of cefprozil (C18H19N3O5S)is dissolved in 45minutes.

Mobile phase ,Cefprozil(Z)-isomer standard preparation,Cefprozil(E)-isomer standard preparation,Resolution solution,and Chromatographic system—Proceed as directed in the Assayunder Cefprozil.

Assay preparation— Transfer an accurately counted number of Tablets,equivalent to about 1500mg of cefprozil,to a 250-mLvolumetric flask containing about 180mLof water.Allow the Tablets to disintegrate with the aid of swirling and sonication.Dilute with water to volume,and mix.Transfer 5.0mLof this solution to a 100-mLvolumetric flask,dilute with water to volume,and mix.Filter a portion of this solution through a filter having a porosity of 0.5µm or finer,and use the filtrate as the Assay preparation.[NOTE—Use this solution within 6hours.]

Procedure— Proceed as directed for Procedurein the Assayunder Cefprozil.Calculate the quantity,in mg,of cefprozil (Z)-isomer and cefprozil (E)-isomer in each Tablet taken by the formula: in which Nis the number of Tablets taken,and the other terms are as defined therein.Calculate the quantity,in mg,of cefprozil (C18H19N3O5S)taken by adding quantities,in mg,determined for the cefprozil (Z)-isomer and for the cefprozil (E)-isomer in each Tablet.