Oxymetholone Tablets
» Oxymetholone Tablets contain not less than 90.0 percent and not more than 110.0 percent of the labeled amount of C21H32O3.
Packaging and storage— Preserve in well-closed containers.
USP Reference standards 11
USP Oxymetholone RS Click to View Structure
Identification— Mix an amount of powdered Tablets, equivalent to about 50 mg of oxymetholone, with 15 mL of solvent hexane, and stir occasionally for 15 minutes. Centrifuge the mixture, and decant and discard the solvent hexane. Extract the residue with two 10-mL portions of solvent hexane, centrifuging and decanting as before, and discard the solvent hexane. Add 25 mL of chloroform to the residue, mix by shaking for 1 to 2 minutes, and filter. Evaporate the filtrate to about 3 mL, add a few mL of solvent hexane to induce crystallization, and evaporate to dryness: the IR absorption spectrum of a potassium bromide dispersion prepared from the oxymetholone so obtained, and previously dried, exhibits maxima only at the same wavelengths as that of a similar preparation of USP Oxymetholone RS, crystallized from the same solvent mixture.
Dissolution 711
Medium: 0.05 M pH 8.5 alkaline borate buffer (see under Solutions in the section Reagents, Indicators, and Solutions); 900 mL.
Apparatus 1: 100 rpm.
Time: 45 minutes.
Procedure— Determine the amount of C21H32O3 dissolved from UV absorbances at the wavelength of maximum absorbance at about 313 nm of filtered portions of the solution under test, suitably diluted with Dissolution Medium if necessary, in comparison with a Standard solution having a known concentration of USP Oxymetholone RS in the same medium. [note—An amount of acetonitrile not to exceed 5% of the total volume of the Standard solution may be used to bring the Reference Standard into solution prior to dilution with Dissolution Medium. ]
Tolerances— Not less than 75% (Q) of the labeled amount of C21H32O3 is dissolved in 45 minutes.
Uniformity of dosage units 905: meet the requirements.
Procedure for content uniformity— Transfer 1 finely powdered Tablet to a 100-mL volumetric flask with the aid of about 75 mL of methanol. Heat the methanol to boiling, and allow to remain at a temperature just below the boiling point for 15 minutes with occasional swirling. Cool to room temperature, dilute with methanol to volume, and mix. Centrifuge a portion of the mixture at about 2000 rpm until the solution becomes clear. Transfer a portion of the supernatant, equivalent to about 1 mg of oxymetholone, to a 100-mL volumetric flask. Add 10 mL of a 1 in 250 solution of sodium hydroxide in methanol, and dilute with methanol to volume. Without delay, concomitantly determine the absorbances of this solution and a freshly prepared Standard solution of USP Oxymetholone RS in the same medium having a known concentration of about 10 µg per mL in 1-cm cells at the wavelength of maximum absorbance at about 315 nm, with a suitable spectrophotometer, using a 1 in 2500 solution of sodium hydroxide in methanol as the blank. Calculate the quantity, in mg, of C21H32O3 in the Tablet taken by the formula:
(TC / D)(AU / AS)
in which T is the labeled quantity, in mg, of oxymetholone in the Tablet, C is the concentration, in µg per mL, of USP Oxymetholone RS in the Standard solution, D is the concentration, in µg per mL, of oxymetholone in the solution from the Tablet, based upon the labeled quantity per Tablet and the extent of dilution, and AU and AS are the absorbances of the solution from the Tablet and the Standard solution, respectively.
Assay— Weigh and finely powder not less than 20 Tablets. Transfer an accurately weighed portion of the powder, equivalent to about 20 mg of oxymetholone, to a separator, add 10 mL of water, and extract with three 25-mL portions of chloroform, filtering each extract through chloroform-washed cotton. Evaporate the combined chloroform extracts on a steam bath to dryness, reducing the application of heat as dryness is approached. Dissolve the residue in methanol, transfer to a 100-mL volumetric flask, dilute with methanol to volume, and mix. Transfer 5.0 mL of the solution to a 100-mL volumetric flask, add 10 mL of a 1 in 250 solution of sodium hydroxide in methanol, dilute with methanol to volume, and mix. Without delay, concomitantly determine the absorbances of this solution and a freshly prepared Standard solution of USP Oxymetholone RS in the same medium having a known concentration of about 10 µg per mL in 1-cm cells at the wavelength of maximum absorbance at about 315 nm, with a suitable spectrophotometer, using a 1 in 2500 solution of sodium hydroxide in methanol as the blank. Calculate the quantity, in mg, of C21H32O3 in the portion of Tablets taken by the formula:
2C(AU / AS)
in which C is the concentration, in µg per mL, of USP Oxymetholone RS in the Standard solution, and AU and AS are the absorbances of the solution from the Tablets and the Standard solution, respectively.
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Topic/Question Contact Expert Committee
Monograph Mary S. Waddell
Scientific Liaison
1-301-816-8124
(SM42010) Monographs - Small Molecules 4
Reference Standards RS Technical Services
1-301-816-8129
rstech@usp.org
711 Margareth R.C. Marques, Ph.D.
Senior Scientific Liaison
1-301-816-8106
(GCDF2010) General Chapters - Dosage Forms
USP35–NF30 Page 4183