Sennosides Tablets
Sennosides Tablets contain NLT 90.0% and NMT 110.0% of the labeled amount of Sennosides.
•  A. Thin-Layer Chromatographic Identification Test
Solvent:  Ethyl acetate, n-propyl alcohol, and water (1:1:1). Shake well, and discard the upper layer.
Standard solution:  1 mg/mL of USP Sennosides RS in Solvent
Sample solution:  Shake a portion of finely powdered Tablets equivalent to 20 mg of sennosides with 20 mL of Solvent.
Chromatographic system 
Adsorbent:  0.25-mm layer of chromatographic silica gel mixture
Application volume:  20 µL
Developing solvent system:  Ethyl acetate, n-propyl alcohol, and water (4:4:3)
Analysis:  Proceed as directed in the chapter. Apply the solutions, as 1-cm streaks, on a line 2.5 cm from the bottom edge of a thin-layer chromatographic plate. Examine the plate under long-wavelength UV light. Expose the plate to ammonium hydroxide vapor until color develops (about 5 min). Cover the plate with a piece of glass, and heat at 120 for 5 min.
Acceptance criteria:  The two most prominent spots from the Sample solution correspond in color and mobility to those from the Standard solution.
•  Procedure
Buffer:  Dissolve 4.54 g of monobasic potassium phosphate in water to make 500 mL of solution. Dissolve 4.73 g of anhydrous dibasic sodium phosphate in water to make 500 mL of solution. Mix 38.9 mL of the monobasic potassium phosphate solution with 61.1 mL of the dibasic sodium phosphate solution. Adjust, if necessary, to a pH of 7.0 with the dibasic sodium phosphate solution.
Borate solution:  37.9 g/L of sodium borate in water
Sodium dithionite solution:  15 g/L of sodium dithionite in water
Standard solution:  1 mg/mL of USP Sennosides RS in Buffer. Dissolve with the aid of an ultrasonic bath.
Sample solution:  Weigh and finely powder NLT 20 Tablets. Transfer a portion of the powder, equivalent to 25 mg of sennosides, to a 25-mL volumetric flask. Add 20 mL of Buffer, and sonicate to dissolve. Add additional Buffer to volume. Centrifuge the resulting suspension for 15 min at 3500 rpm. Use the supernatant.
Instrumental conditions 
Mode:  Fluorescence
Excitation wavelength:  392 nm
Emission wavelength:  505 nm
Samples:  Standard solution and Sample solution
Pipet 1-mL portions of the Standard solution and the Sample solution into separate 100-mL volumetric flasks, and dilute with Borate solution to volume. Transfer 5.0-mL portions of each of the resulting solutions to separate low-actinic glass, 50-mL volumetric flasks, and add 15 mL of Borate solution and 15.0 mL of Sodium dithionite solution. Pass nitrogen through the solutions, seal the flasks with nitrogen-filled balloons, and heat in a water bath for 30 min. Cool the flasks for 15 min in a water bath thermostatically controlled at 20. Dilute the solutions with Borate solution to volume. Determine without delay the fluorescence intensities of the resulting solutions, for which the time elapsed between the addition of Sodium dithionite solution and the measurement is the same.
Calculate the percentage of the labeled amount of sennosides in the portion of Tablets taken:
Result = (IU/IS) × (CS/CU) × 100
IU== fluorescence value observed in the Sample solution
IS== fluorescence value observed in the Standard solution
CS== concentration of USP Sennosides RS in the Standard solution (mg/mL)
CU== nominal concentration of sennosides in the Sample solution (mg/mL)
Acceptance criteria:  90.0%–110.0%
•  Dissolution 711
Medium:  Water; 900 mL
Apparatus 1:  100 rpm
Time:  120 min
Analysis:  Determine the amount of sennosides dissolved, using the procedure set forth in the Assay, making any necessary volumetric adjustments.
Tolerances:  NLT 75% (Q) of the labeled amount of sennosides is dissolved.
•  Uniformity of Dosage Units 905: Meet the requirements
•  Packaging and Storage: Preserve in well-closed containers.
•  USP Reference Standards 11
USP Sennosides RS Click to View Structure
Auxiliary Information— Please check for your question in the FAQs before contacting USP.
Topic/Question Contact Expert Committee
Monograph Maged H. Sharaf, Ph.D.
Principal Scientific Liaison
(DS2010) Monographs - Dietary Supplements
711 Margareth R.C. Marques, Ph.D.
Senior Scientific Liaison
(GCDF2010) General Chapters - Dosage Forms
Reference Standards RS Technical Services
USP35–NF30 Page 4628