Medium: water;900mL.

Apparatus 1: 100rpm.

Time: 120minutes.

Procedure— Determine the amount of sennosides dissolved,employing the procedure set forth in the Assay,making any necessary volumetric adjustments.

Tolerances— Not less than 75%(Q)of the labeled amount of sennosides is dissolved in 120minutes.

pH7.0phosphate buffer,Borate solution,Sodium dithionite solution,and Standard preparation— Prepare as directed in the Assayunder Sennosides.

Assay preparation— Weigh and finely powder not less than 20Tablets.Transfer an accurately weighed portion of the powder,equivalent to about 25mg of sennosides,to a 25-mLvolumetric flask.Add 20mLof pH7.0phosphate buffer,sonicate to dissolve the sennosides,add pH7.0phosphate bufferto volume,and mix.Centrifuge the resulting suspension for 15minutes at 3500rpm.The supernatant is the Assay preparation.

Procedure— Proceed as directed for Procedurein the Assayunder Sennosides.Calculate the quantity,in mg,of sennosides in the portion of Tablets taken by the formula: in which Cis the concentration,in mg per mL,of USP Sennosides RS,corrected for loss on drying,in the Standard preparation,and IUand ISare the fluorescence values observed for the solutions from the Assay preparationand the Standard preparation,respectively.