Norgestrel Tablets
»Norgestrel Tablets contain not less than 90.0percent and not more than 110.0percent of the labeled amount of Norgestrel (C21H28O2).
Packaging and storage— Preserve in well-closed containers.
Identification— Finely powder 20Tablets,triturate the powder with 5mLof chloroform,and allow the solids to settle.Apply 60µLof the extract and 60µLof a chloroform solution containing about 300µg of USP Norgestrel RSper mLat points about 3cm from one edge of a thin-layer chromatographic plate (see Chromatography á621ñ)coated with a 0.25-mm layer of chromatographic silica gel mixture.Place the plate in a developing chamber containing a mixture of chloroform and alcohol (96:4)to a depth of 2cm,the chamber having been previously equilibrated with the solvent mixture.Remove the plate when the solvent has moved about 15cm from the line of application,dry at room temperature,spray with a mixture of 80volumes of sulfuric acid and 20volumes of alcohol,and heat at 105for several minutes:the spot from the solution under test exhibits an RFvalue identical to that of the spot from the Standard solution,and,when viewed under long-wavelength UVlight,exhibits a red fluorescence similar to that from the Standard solution.
Disintegration á701ñ: 15minutes,the use of disks being omitted.
Uniformity of dosage units á905ñ: meet the requirements.
Assay—
Isoniazid reagent— Dissolve 0.25g of isoniazid and 0.3mLof hydrochloric acid in 500mLof dehydrated alcohol.
Procedure— Weigh and finely powder not less than 20Tablets.Transfer an accurately weighed portion of the powder,equivalent to about 75µg of norgestrel,to a 30-mLseparator containing 5mLof water.Extract with three 5-mLportions of chloroform,shaking for about 1minute each time,and collecting the chloroform extracts through glass wool,previously moistened with chloroform,into a glass-stoppered test tube.Add 1mLof dilute hydrochloric acid (1in 12)to the remaining aqueous phase and extract with a fourth 5-mLportion of chloroform,collecting this chloroform extract as before and combining it with the previous three.To another glass-stoppered test tube transfer 20.0mLof a solution of USP Norgestrel RS,in chloroform,having a known concentration of about 3.75µg per mL.Evaporate the contents of both tubes in a water bath with the aid of a current of air to dryness.Add 5.0mLof Isoniazid reagentto each tube,insert the stopper in each tube,and swirl occasionally for 1hour.Concomitantly determine the absorbances of both solutions in 1-cm cells,at the wavelength of maximum absorbance at about 380nm,using a suitable spectrophotometer,and using Isoniazid reagentas the blank.Calculate the quantity,in µg,of C21H28O2in the portion of Tablets taken by the formula:
20C(AU/AS),
in which Cis the concentration,in µg per mL,of USP Norgestrel RSin the Standard solution,and AUand ASare the absorbances of the solutions from the Tablets and the Standard solution,respectively.
Auxiliary Information— Staff Liaison:Clydewyn M.Anthony,Ph.D.,Scientist
Expert Committee:(PA1)Pharmaceutical Analysis 1
USP28–NF23Page 1403
Phone Number:1-301-816-8139