Medium: water containing 5.4mg of sodium lauryl sulfate per mL;1000mL.

Apparatus 2: 50rpm.

Time: 30minutes.

Procedure— Determine the amount of C17H17ClO6dissolved from UVabsorbances at the wavelength of maximum absorbance at about 291nm of filtered portions of the solution under test,suitably diluted with a solution of methanol and water (4:1),if necessary,in comparison with a Standard solution having a known concentration of USP Griseofulvin RSin the same medium.

Tolerances— Not less than 80%(Q)of the labeled amount of C17H17ClO6is dissolved in 30minutes.

Procedure for content uniformity— Transfer the contents of 1Capsule to a suitable container,add an accurately measured volume of methanol sufficient to yield a concentration of griseofulvin not greater than 1mg per mL,shake by mechanical means for 1hour,or longer if necessary to disperse the specimen completely,and sonicate for 1minute.Centrifuge a portion of this solution,and quantitatively dilute an accurately measured volume of the clear supernatant to obtain a test solution containing about 10µg of griseofulvin per mL.Concomitantly determine the absorbances of the test solution and a Standard solution of USP Griseofulvin RSin methanol having a known concentration of about 10µg per mLat the wavelength of maximum absorbance at about 292nm,with a suitable spectrophotometer,using methanol as the blank.Calculate the quantity,in mg,of griseofulvin (C17H17ClO6)in the Capsule taken by the formula: in which Cis the concentration,in µg per mL,of USP Griseofulvin RSin the Standard solution;Lis the labeled quantity,in mg,of griseofulvin in the Capsule;Dis the concentration,in µg per mL,of griseofulvin in the test solution,based on the labeled quantity per Capsule and the extent of dilution;and AUand ASare the absorbances of the test solution and the Standard solution,respectively.

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

Assay preparation— Remove,as completely as possible,the contents of not fewer than 20Capsules,and weigh accurately.Mix,and transfer an accurately weighed portion of the powder,equivalent to about 125mg of griseofulvin,to a 100-mLvolumetric flask.Add about 70mLof methanol,shake by mechanical means for 30minutes,dilute with methanol to volume,and mix.Filter a portion of this solution,discarding the first 5mLof the filtrate.Transfer 5.0mLof the clear filtrate to a 50-mLvolumetric flask,dilute with Mobile phaseto volume,and mix.

Procedure— Proceed as directed for Procedurein the Assayunder Griseofulvin.Calculate the quantity,in mg,of griseofulvin (C17H17ClO6)in the portion of Capsules taken by the formula: in which Cis the concentration,in mg per mL,of USP Griseofulvin RSin the Standard preparation,and the other terms are as defined therein.