Medium: water; 900 mL.

Apparatus 1: 100 rpm.

Time: 45 minutes.

Procedure— Determine the amount of C7H6KNO2 dissolved by employing UV absorption at the wavelength of maximum absorbance at about 270 nm on filtered portions of the solution under test, suitably diluted with Medium, in comparison with a Standard solution having a known concentration of USP Aminobenzoate Potassium RS in the same Medium.

Tolerances— Not less than 75% (Q) of the labeled amount of C7H6KNO2 is dissolved in 45 minutes.

(Official January 1, 2007)

Standard preparation— Prepare a solution of USP Aminobenzoate Potassium RS having a known concentration of about 5 µg per mL.

Assay preparation and Procedure—Weigh and finely powder not fewer than 20 Tablets. Using a portion of the powdered Tablets, equivalent to about 100 mg of aminobenzoate potassium, proceed as directed in the Assay under Aminobenzoate Potassium Capsules.