Medium: water;use 500mLof the Dissolution Mediumfor Tablets labeled to contain 10mg of prednisone or less,and 900mLfor Tablets labeled to contain more than 10mg of prednisone.

Apparatus 2: 50rpm.

Time: 30minutes.

Procedure— Determine the amount of C21H26O5dissolved from UVabsorbances at the wavelength of maximum absorbance at about 242nm 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 Prednisone RSin the same medium.An amount of alcohol not to exceed 5%of the total volume of the Standard solution may be used to bring the prednisone standard into solution prior to dilution with water.

Tolerances— Not less than 80%(Q)of the labeled amount of C21H26O5is dissolved in 30minutes.

Procedure for content uniformity—

Mobile phase,Internal standard solution,Standard preparation,andChromatographic system— Proceed as directed in the Assayunder Prednisone.

Test preparation— Place 1Tablet in a volumetric flask of such size that when the contents are diluted to volume the resulting solution has a concentration of about 0.2mg of prednisone per mL.Add 5mLof water,swirl,sonicate for 1minute,add a volume of methanol equal to one-half the volume of the volumetric flask,and sonicate again for 1minute.Dilute with water to volume,and mix.Transfer 5.0mLof this solution and 5.0mLof the Internal standard solutionto a 50-mLvolumetric flask,add dilute methanol (1in 2)to volume,and mix.Filter through a 5-µm filter,discarding the first 20mLof the filtrate.

Procedure— Proceed as directed for Procedurein the Assayunder Prednisone,except to calculate the quantity,in mg,of C21H26O5in the Tablet taken by the formula: in which Dis the dilution factor for the Test preparationand the other terms are as defined therein.

Mobile phase,Internal standard solution,Standard preparation,andChromatographic system— Proceed as directed in the Assayunder Prednisone.

Assay preparation— Weigh and finely powder not less than 20Tablets.Transfer an accurately weighed portion of the powder,equivalent to about 20mg of prednisone,to a 100-mLvolumetric flask.Add 5mLof water,sonicate for 1minute,add 50mLof methanol,and sonicate again for 1minute.Dilute with water to volume,and mix.Transfer 5.0mLof this solution and 5.0mLof the Internal standard solutionto a 50-mLvolumetric flask,add dilute methanol (1in 2)to volume,and mix.Filter through a 5-µm filter,discarding the first 20mLof the filtrate.

Procedure— Proceed as directed for Procedurein the Assayunder Prednisone,except to calculate the quantity,in mg,of C21H26O5in the portion of Tablets taken by the formula: in which the terms are as defined therein.