Sennosides
»Sennosides is a partially purified natural complex of anthraquinone glucosides found in senna,isolated from Cassia angustifoliaor C.acutifoliaas calcium salts.It contains not less than 90.0percent and not more than 110.0percent of sennosides,calculated on the dried basis,or,if the sennosides is in higher concentration,not less than 90.0percent and not more than 110.0percent of the concentration indicated on the label.
Packaging and storage—
Preserve in well-closed containers.
Identification—
Place equal volumes of ethyl acetate,n-propyl alcohol,and water in a separator,shake,and discard the upper layer.Add a sufficient quantity of Sennosides to obtain a solution having a concentration of 1mg per mL.Prepare similarly a Standard solution of USP Sennosides RS.Apply 20-µLportions of each solution,as 1-cm streaks,on a line about 2.5cm from the bottom edge of a thin-layer chromatographic plate (see Chromatography á621ñ)coated with a 0.25-mm layer of chromatographic silica gel mixture.Develop the chromatogram in a solvent system consisting of a mixture of ethyl acetate,n-propyl alcohol,and water (4:4:3)until the solvent front has moved about 15cm.Remove the plate from the developing chamber,air-dry,and examine under long-wavelength UVlight.Expose the plate to ammonium hydroxide vapor until color develops (about 5minutes).Cover the plate with a piece of glass,and heat at 120
for 5minutes:the 2most prominent spots from the test solution corresponds in color and mobility to those from the Standard solution.
for 5minutes:the 2most prominent spots from the test solution corresponds in color and mobility to those from the Standard solution.
pHá791ñ:
between 6.3and 7.3,in a solution (1in 10).
Loss on drying á731ñ—
Dry it in vacuum at 100to constant weight:it loses not more than 5.0%of its weight.
to constant weight:it loses not more than 5.0%of its weight.
Residue on ignition á281ñ:
between 5.0%and 8.0%,the use of sulfuric acid being omitted.
Heavy metals,Method IIá231ñ:
0.006%.
Assay—
pH7.0phosphate buffer—
Dissolve 4.54g of monobasic potassium phosphate in water to make 500mLof solution.Dissolve 4.73g of anhydrous dibasic sodium phosphate in water to make 500mLof solution.Mix 38.9mLof the monobasic potassium phosphate solution with 61.1mLof the dibasic sodium phosphate solution.Adjust dropwise,if necessary,with the dibasic sodium phosphate solution to a pHof 7.0.
Borate solution—
Dissolve 75.80g of sodium borate in water,dilute with water to 2000mL,and mix.
Sodium dithionite solution—
Prepare a 1.5in 100solution of sodium dithionite in water.
Standard preparation—
Dissolve about 25mg of USP Sennosides RS,accurately weighed,in pH7.0phosphate bufferin a 25-mLvolumetric flask with the aid of an ultrasonic bath,dilute with pH7.0phosphate bufferto volume,and mix.
Assay preparation—
Dissolve about 25mg of Sennosides,accurately weighed,in pH7.0phosphate bufferin a 25-mLvolumetric flask,with the aid of an ultrasonic bath,dilute with pH7.0phosphate bufferto volume,and mix.
Procedure—
Pipet 1-mLportions of the Standard preparationand the Assay preparationinto separate 100-mLvolumetric flasks,dilute with Borate solutionto volume,and mix.Transfer 5.0-mLportions of each of the resulting solutions to separate low-actinic glass,50-mLvolumetric flasks,and add 15mLof Borate solutionand 15.0mLof Sodium dithionite solution.Pass nitrogen through the solutions,seal the flasks with nitrogen-filled balloons,and heat in a water bath for 30minutes.Cool the flasks for 15minutes in a water bath thermostatically controlled at 20.Dilute the solutions with Borate solutionto volume,and mix.Determine without delay the fluorescence intensities of the resulting solutions in a fluorometer at an excitation wavelength of 392nm and an emission wavelength of 505nm,the time elapsed between the addition of the Sodium dithionite solutionand the measurement being the same for the two solutions.Calculate the quantity,in mg,of sennosides in the Sennosides taken by the formula:
.Dilute the solutions with Borate solutionto volume,and mix.Determine without delay the fluorescence intensities of the resulting solutions in a fluorometer at an excitation wavelength of 392nm and an emission wavelength of 505nm,the time elapsed between the addition of the Sodium dithionite solutionand the measurement being the same for the two solutions.Calculate the quantity,in mg,of sennosides in the Sennosides taken by the formula:
25C(IU/IS),
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.
Auxiliary Information—
Staff Liaison:Gabriel I.Giancaspro,Ph.D.,Senior Scientist and Latin American Specialist
Expert Committee:(DSB)Dietary Supplements:Botanicals
USP28–NF23Page 1766
Phone Number:1-301-816-8343