Medium: water;900mL.

Apparatus 2: 50rpm.

Time: 30minutes.

Procedure— Determine the amount of anhydrous loracarbef (C16H16ClN3O4)dissolved from UVabsorbances at the wavelength of maximum absorption at about 260nm of filtered portions of the solution under test,suitably diluted with Dissolution Medium,if necessary,in comparison with a Standard solution having a known concentration of USP Loracarbef RSin the same medium.

Tolerances— Not less than 75%(Q)of the labeled amount of anhydrous loracarbef (C16H16ClN3O4)is dissolved in 30minutes.

Solution A,Solution B,Mobile phase,System suitability solution,Standard solution,and Chromatographic system— Proceed as directed in the test for Related compoundsunder Loracarbef.

Test solution— Remove,as completely as possible,the contents of not less than 5Capsules.Weigh the contents,and determine the average weight of the content of each Capsule.Transfer an accurately weighed portion of the powder,equivalent to 125mg of loracarbef,based on the labeled amount per Capsule,to a 25-mLvolumetric flask.Add about 20mLof Solution Ato the flask,mix,sonicate,and mix on a vortex mixer to aid in dissolution.Dilute with Solution Ato volume,and mix.Filter,and use the filtrate as the Test solutionimmediately,or refrigerate and use within 24hours.

Procedure— Proceed as directed for Procedurein the test for Related compoundsunder Loracarbef,except to omit the injection of Phenylglycine solution.Calculate the percentage of each related compound in the portion of Capsule contents taken by the formula: in which Cis the concentration,in mg per mL,of USP Loracarbef RSin the Standard solution;Yis the concentration,in mg per mL,of loracarbef in the Test solution;riis the response of any related compound obtained from the Test solution;and rSis the loracarbef response obtained from the Standard solution:not more than 1.0%of any individual related compound is found,and the sum of all related compounds is not more than 3.0%.

Mobile phase,Standard preparation,Resolution solution,and Chromatographic system— Proceed as directed in the Assayunder Loracarbef.

Assay preparation— Remove,as completely as possible,the contents of not less than 20Capsules.Transfer an accurately weighed portion of the powder,equivalent to about 10mg of loracarbef,to a 50-mLvolumetric flask.Add about 40mLof Mobile phase,and dissolve with the aid of swirling and sonication.Dilute with Mobile phaseto volume,and mix.Pass a portion of this solution through a filter having a porosity of 0.5µm or finer,and use the filtrate as the Assay preparation.

Procedure— Proceed as directed for Procedurein the Assayunder Loracarbef.Calculate the quantity,in mg,of loracarbef (C16H16ClN3O4)in the portion of Capsules taken by the formula: in which Cis the concentration,in mg per mL,of USP Loracarbef RSin the Standard preparation;Pis the specified potency,in µg of anhydrous loracarbef (C16H16ClN3O4)per mg,of USP Loracarbef RS;and rUand rSare the loracarbef peak responses obtained from the Assay preparationand the Standard preparation,respectively.