Biperiden Hydrochloride Tablets
»Biperiden Hydrochloride Tablets contain not less than 93.0percent and not more than 107.0percent of the labeled amount of C21H29NO·HCl.
Packaging and storage— Preserve in tight containers.
Identification— To a quantity of finely powdered Tablets,equivalent to about 10mg of biperiden hydrochloride,add 5mLof water,mix,and sonicate to disperse the powder.Add 5mLof methanol into the flask,mix,and sonicate for 15minutes.Filter the solution into a separator,add 2mLof 1Nsodium hydroxide and 10mLof chloroform,and shake for 3minutes.Filter the chloroform layer into a stoppered flask,and use the chloroform filtrate as the test solution.In a similar manner,using about 10mg of USP Biperiden Hydrochloride RSin place of the powdered Tablets,prepare the Standard solution.Condition a suitable thin-layer chromatographic plate (see Chromatography á621ñ)coated with a 0.25-mm layer of chromatographic silica gel mixture,by heating the plate at 105for 1hour.Allow the plate to cool,and separately apply 20µLeach of the test solution and the Standard solution to the plate.Allow the applications to dry,and develop the chromatogram in a solvent system consisting of a mixture of methanol and ammonium hydroxide (100:1.5)until the solvent front has moved about three-fourths of the length of the plate.Remove the plate from the developing chamber,mark the solvent front,and allow the solvent to evaporate.Locate the spots on the plate by exposing the plate for 10minutes to iodine vapors in a pre-equilibrated closed chamber,on the bottom of which there are iodine crystals:the RFvalue of the principal spot obtained from the test solution corresponds to that obtained from the Standard solution.
Dissolution á711ñ—
Medium: 0.01Nhydrochloric acid;500mL.
Apparatus 2: 50rpm.
Time: 45minutes.
Determine the amount of C21H29NO·HCl dissolved by employing the following method.
Phosphate buffer–bromocresol purple solution— Prepare as directed in the Assay.
Standard preparation— Dissolve an accurately weighed quantity of USP Biperiden Hydrochloride RSin methanol,and quantitatively dilute with methanol to obtain a solution having a known concentration of about 0.8mg per mL.Pipet 5mLof this solution into a 500-mLvolumetric flask,add 0.01Nhydrochloric acid to volume,and mix.Pipet 25mLof this solution into a suitable beaker,and adjust with 0.01Nsodium hydroxide to a pHof 5.3.Transfer this solution to a 100-mLvolumetric flask with the aid of water,dilute with water to volume,and mix to obtain a Standard preparationhaving a known concentration of about 2µg per mL.
Test preparation— Filter 75mLof the solution under test,pipet 50mLof the clear filtrate into a suitable beaker,and adjust with 0.01Nsodium hydroxide to a pHof 5.3.Transfer this solution to a 100-mLvolumetric flask with the aid of water,dilute with water to volume,and mix.
Procedure— Pipet 20mLeach of the Standard preparation,the Test preparation,and water to provide the blank,into individual separators,each containing 10.0mLof Phosphate buffer–bromocresol purple solution.Extract the solution in each separator with 40.0mLof chloroform for 10minutes.After the layers have separated,pass each chloroform extract through filter paper into separate,glass-stoppered containers,discarding the first 10mLof each filtrate.Determine the amount of C21H29NO·HCl dissolved from absorbances at the wavelength of maximum absorbance at about 408nm (10-cm cells)of the extract from the Test preparationin comparison with that of the extract from the Standard preparation,using the blank to set the instrument.
Tolerances— Not less than 75%(Q)of the labeled amount of C21H29NO·HCl is dissolved in 45minutes.
Uniformity of dosage units á905ñ: meet the requirements.
Assay—
Phosphate buffer–bromocresol purple solution— Dissolve 38g of monobasic sodium phosphate and 2g of anhydrous dibasic sodium phosphate in water to make 1000mL.Adjust the pHof the solution to 5.3±0.1,if necessary (Solution A).Dissolve 400mg of bromocresol purple in 30mLof water,add 6.3mLof 0.1Nsodium hydroxide,and dilute with water to 500mL(Solution B).Mix equal volumes of Solution A,Solution B,and chloroform,shake in a separator,and discard the chloroform.If appreciable color is extracted,repeat with additional portions of chloroform until no color is extracted.
Standard preparation— Transfer about 80mg of USP Biperiden Hydrochloride RS,accurately weighed,to a 100-mLvolumetric flask,add methanol to volume,and mix.Transfer 5.0mLof this solution to a second 100-mLvolumetric flask,add 25mLof water,dilute with methanol to volume,and mix.The concentration of USP Biperiden Hydrochloride RSin the Standard preparationis about 40µg per mL.
Assay preparation— Weigh and finely powder not less than 20Tablets.Transfer an accurately weighed portion of the powder,equivalent to about 2mg of biperiden hydrochloride,to a 50-mLvolumetric flask,add 12.5mLof water,and heat on a steam bath for 15minutes.Cool,dilute with methanol to volume,and mix.
Procedure— Transfer 5.0mLeach of the Standard preparation,the Assay preparation,and a mixture of methanol and water (3:1)to provide the blank,to individual separators each,containing 10.0mLof Phosphate buffer–bromocresol purple solution.Extract the solution in each separator with 20.0mLof chloroform for 2minutes.After the layers have separated,pass each chloroform extract through filter paper (Whatman No.31or equivalent)into separate glass-stoppered,50-mLvolumetric flasks.In the same manner,extract the solution in each separator with another 20.0-mLportion of chloroform,filter,and wash each filter with 8mLof chloroform,collecting each combined filtrate and washing,respectively,in the 50-mLvolumetric flask containing the first extract.Dilute with chloroform to volume,and mix.Concomitantly determine the absorbances of the solutions in 1-cm cells at the wavelength of maximum absorbance at about 408nm,with a suitable spectrophotometer,using the blank to set the instrument.Calculate the quantity,in mg,of C21H29NO·HCl in the portion of Tablets taken by the formula:
0.05C(AU/AS),
in which Cis the concentration,in µg per mL,of USP Biperiden Hydrochloride RSin the Standard preparation,and AUand ASare the absorbances of the solutions from the Assay preparationand the Standard preparation,respectively.
Auxiliary Information— Staff Liaison:Salvador C.Salado,M.S.,Scientist and Latin American Liaison
Expert Committee:(PA3)Pharmaceutical Analysis 3
USP28–NF23Page 261
Phone Number:1-301-816-8165