Methyltestosterone Capsules
»Methyltestosterone Capsules contain not less than 90.0percent and not more than 110.0percent of the labeled amount of methyltestosterone (C20H30O2).
Packaging and storage— Preserve in well-closed containers.
Identification— Evaporate 25mLof the first alcohol solution of methyltestosterone obtained in the Assayto dryness:the IRabsorption spectrum of a potassium bromide dispersion of the residue so obtained exhibits maxima at the same wavelengths as that of a similar preparation of USP Methyltestosterone RS.
Dissolution á711ñ—
Medium: water;900mL.
Apparatus 1: 100rpm.
Time: 45minutes.
Procedure— Determine the amount in solution on filtered portions of the Dissolution Medium,suitably diluted quantitatively and stepwise with water to obtain a solution containing about 10µg of methyltestosterone per mLat the wavelength of maximum absorbance at about 248nm,with a suitable spectrophotometer,in comparison with a solution of USP Methyltestosterone RSin the same medium at the same concentration,water being used as the blank.
Tolerances— Not less than 70%(Q)of the labeled amount of C20H30O2is dissolved in 45minutes.
Uniformity of dosage units á905ñ: meet the requirements.
Procedure for content uniformity— Transfer the contents of 1Capsule to a 100-mLvolumetric flask,add 50mLof methanol,and shake by mechanical means for 60minutes.Dilute with methanol to volume,and filter,discarding the first 20mLof the filtrate.Dilute a portion of the subsequent filtrate quantitatively and stepwise,if necessary,with methanol to obtain a solution containing about 10µg of methyltestosterone per mL.Concomitantly determine the absorbances of this solution and a Standard solution of USP Methyltestosterone RSin the same medium having a known concentration of about 10µg per mL,in 1-cm cells at the wavelength of maximum absorbance at about 241nm,with a suitable spectrophotometer,using methanol as the blank.Calculate the quantity,in mg,of C20H30O2in the Capsule taken by the formula:
(T/D)C(AU/AS),
in which Tis the labeled quantity,in mg,of methyltestosterone in the Capsule;Dis the concentration,in µg per mL,of methyltestosterone in the solution from the Capsule,based on the labeled quantity per Capsule and the extent of dilution;Cis the concentration,in µg per mL,of USP Methyltestosterone RSin the Standard solution;and AUand ASare the absorbances of the solution from the Capsule and the Standard solution,respectively.
Assay— Remove as completely as possible and weigh the contents of not less than 20Capsules,and mix.Transfer an accurately weighed portion of the powder,equivalent to about 10mg of methyltestosterone,to a 125-mLseparator with the aid of about 5mLof water.Extract with four 20-mLportions of chloroform,filtering each through chloroform-washed cotton.Evaporate the combined extracts on a steam bath,with the aid of a current of air,to dryness.Dissolve the residue in alcohol,transfer to a 50-mLvolumetric flask,add alcohol to volume,and mix.Pipet a 5-mLaliquot into a 100-mLvolumetric flask,add alcohol to volume,and mix.Concomitantly determine the absorbances of this solution and a Standard solution of USP Methyltestosterone RSin the same medium having a known concentration of about 10µg per mL,in 1-cm cells at the wavelength of maximum absorbance at about 241nm,with a suitable spectrophotometer,using alcohol as the blank.Calculate the quantity,in mg,of methyltestosterone (C20H30O2)in the portion of Capsules contents taken by the formula:
C(AU/AS),
in which Cis the concentration,in µg per mL,of USP Methyltestosterone RSin the Standard solution;and AUand ASare the absorbances of the solution from the Capsules and the Standard solution,respectively.
Auxiliary Information— Staff Liaison:Clydewyn M.Anthony,Ph.D.,Scientist
Expert Committee:(PA1)Pharmaceutical Analysis 1
USP28–NF23Page 1273
Phone Number:1-301-816-8139