Medium: 0.05 M Tris(hydroxymethyl)aminomethane, pH 7.6, adjusted, if necessary, with hydrochloric acid to a pH of 7.6; 900 mL.

Apparatus 2: 75 rpm.

Time: 30 minutes.

Procedure— Determine the amount of C14H21N3O3S dissolved from UV absorbances at the wavelength of maximum absorbance at about 224 nm of filtered portions of the solution under test, suitably diluted with Dissolution Medium, in comparison with a Standard solution having a known concentration of USP Tolazamide RS in the same medium. [note—Sonicate the Standard solution until the Reference Standard is dissolved.]

Tolerances— Not less than 70% (Q) of the labeled amount of C14H21N3O3S is dissolved in 30 minutes.

Internal standard preparation , Mobile phase, and Standard preparation—Prepare as directed in the Assay under Tolazamide.

Assay preparation— Weigh and finely powder not less than 10 Tablets. Weigh accurately a portion of the powder, equivalent to about 300 mg of tolazamide, and transfer to a suitable container. Add 100.0 mL of Internal standard solution and about 20 glass beads. Securely close the container, and shake vigorously for approximately 30 minutes. Centrifuge, and use the clear liquid as the Assay preparation.

Procedure— Proceed as directed for Procedure in the Assay under Tolazamide. Calculate the quantity, in mg, of C14H21N3O3S in the portion of Tablets taken by the formula: in which the terms are as defined therein.