Medium: 0.07 M pH 7.0 phosphate buffer, prepared by dissolving 3.7 g of monobasic sodium phosphate and 5.7 g of anhydrous dibasic sodium phosphate in 1000 mL of water; 900 mL.

Apparatus 2: 50 rpm.

Time: 30 minutes.

Procedure— Test 5.0 mL of constituted Cefuroxime Axetil for Oral Suspension equivalent to 125 or 250 mg of cefuroxime (C16H16N4O8S). Determine the amount of cefuroxime equivalent (C16H16N4O8S) dissolved by employing UV absorption at the wavelength of maximum absorbance at about 280 nm on 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 Cefuroxime Axetil RS in the same Medium.

Tolerances— Not less than 60% (Q) of the labeled amount of C16H16N4O8S is dissolved in 30 minutes.

FOR SOLID PACKAGED IN SINGLE-UNIT CONTAINERS— Constitute Cefuroxime Axetil for Oral Suspension as directed in the labeling. Mix, and allow the contents of the container to drain into a beaker for 5 seconds. Withdraw and assay 5.0 mL of Cefuroxime Axetil for Oral Suspension from the beaker, or the total amount if it is less than 5 mL. It meets the requirements.

FOR SOLID PACKAGED IN MULTIPLE-UNIT CONTAINERS— Constitute Cefuroxime Axetil for Oral Suspension as directed in the labeling. It meets the requirements.

(Official January 1, 2007)

0.2 M Monobasic ammonium phosphate, Mobile phase, and Chromatographic system— Proceed as directed in the Assay under Cefuroxime Axetil.

Resolution solution— In a 50-mL volumetric flask, mix 10.0 mL of a solution of USP Cefuroxime Axetil RS in methanol containing 1.2 mg per mL, 5.0 mL of methanol, and 3.8 mL of a solution of USP Cefuroxime Axetil Delta-3 Isomers RS in methanol containing 0.16 mg per mL. Dilute with 0.2 M Monobasic ammonium phosphate to volume, and mix.

Standard preparation— Transfer about 30 mg of USP Cefuroxime Axetil RS, accurately weighed, to a 25-mL volumetric flask, dissolve in and dilute with methanol to volume, and mix. Promptly transfer 10.0 mL of this solution to a 50-mL volumetric flask, add 8.8 mL of methanol, dilute with 0.2 M Monobasic ammonium phosphate to volume, and mix.

Assay preparation— Transfer to a 100-mL volumetric flask an accurately measured portion of Cefuroxime Axetil for Oral Suspension, freshly mixed and free from air bubbles, constituted as directed in the labeling, and equivalent to about 250 mg of cefuroxime. Add about 50 mL of methanol, and shake by mechanical means for about 10 minutes. Dilute with methanol to volume, and mix. Filter a portion of this stock solution, and transfer 5.0 mL of the filtrate to a 50-mL volumetric flask. Add 13.8 mL of methanol, dilute with 0.2 M Monobasic ammonium phosphate to volume, and mix. [NOTE—Protect this Assay preparation from light and use promptly, or refrigerate and use on the day prepared.]

Procedure— Proceed as directed in the Assay under Cefuroxime Axetil. Calculate the quantity, in mg, of cefuroxime (C16H16N4O8S) in each mL of Cefuroxime Axetil for Oral Suspension taken by the formula: in which V is the volume, in mL, of Cefuroxime Axetil for Oral Suspension taken to prepare the Assay preparation; rU and rS are the sums of the peak responses of the cefuroxime axetil diastereoisomers A and B obtained from the Assay preparation and the Standard preparation, respectively; and the other terms are as defined therein.