Apomorphine Hydrochloride Tablets
» Apomorphine Hydrochloride Tablets contain not less than 90.0 percent and not more than 110.0 percent of the labeled amount of C17H17NO2·HCl·½H2O.
Packaging and storage— Preserve in tight, light-resistant containers.
Color of solution— Dissolve a quantity of powdered Tablets, equivalent to 5 mg of apomorphine hydrochloride, in water to make 100.0 mL. Transfer 1.0 mL of the solution to a test tube, dilute with 6 mL of water, and, if necessary, filter through a small pledget of cotton. Add 1 mL of sodium bicarbonate solution (1 in 20), then add 0.50 mL of iodine TS. Allow to stand for 30 seconds, then add 0.60 mL of sodium thiosulfate solution (1 in 40), and dilute with water to 10 mL. This solution represents the color standard.
Place a quantity of powdered Tablets, equivalent to about 50 mg of apomorphine hydrochloride, in a test tube of suitably small size, add 10.0 mL of cold, oxygen-free water, insert the stopper in the test tube, and agitate gently until no more dissolves; if necessary, filter immediately through a small pledget of cotton. The color of the solution, observed promptly after preparation, is not more intense than that of the color standard. Use closely matched test tubes for the comparison.
Identification— To 5 mL of a filtered solution of Tablets, containing about 10 mg of apomorphine hydrochloride, add a slight excess of sodium bicarbonate solution (1 in 20): a white or greenish-white precipitate is formed. Add 3 drops of iodine TS, and shake vigorously: an emerald-green color is produced. Add 5 mL of ether, and, after vigorous shaking, allow the layers to separate: the ether is colored deep ruby-red while the water layer retains its green color.
Disintegration 701: 15 minutes.
Uniformity of dosage units 905: meet the requirements.
Procedure for content uniformity— Place 1 Tablet in a 500-mL volumetric flask containing 100 mL of 0.1 N hydrochloric acid, and shake for 15 minutes. Dilute with 0.1 N hydrochloric acid to volume, mix, and filter, discarding the first 20 mL of filtrate. Dilute a portion of the subsequent filtrate quantitatively and stepwise, if necessary, with 0.1 N hydrochloric acid to provide a solution containing approximately 12 µg of apomorphine hydrochloride per mL. Concomitantly determine the absorbances of this solution and of a solution of USP Apomorphine Hydrochloride RS in the same medium having a known concentration of about 12 µg of anhydrous apomorphine hydrochloride per mL, in 1-cm cells at the wavelength of maximum absorbance at about 273 nm, with a suitable spectrophotometer, using 0.1 N hydrochloric acid as the blank. Calculate the quantity, in mg, of C17H17NO2·HCl·½H2O in the Tablet taken by the formula:
(312.80 / 303.79)(TC / D)(AU / AS)
in which 312.80 and 303.79 are the molecular weights of apomorphine hydrochloride hemihydrate and anhydrous apomorphine hydrochloride, respectively; T is the labeled quantity, in mg, of apomorphine hydrochloride in the Tablet; C is the concentration, in µg per mL, of anhydrous apomorphine hydrochloride in the Standard solution; D is the concentration, in µg per mL, of apomorphine hydrochloride 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 fewer than 20 Tablets. Dissolve an accurately weighed portion of the powder, equivalent to about 50 mg of apomorphine hydrochloride, in 25 mL of water in a separator, add 500 mg of sodium bicarbonate, and completely extract with successive small portions of ether. Combine the ether extracts in a separator, and wash them with three 5-mL portions of water. Shake the combined water washings with 10 mL of ether, and add this ether to the combined ether extracts. Extract the ether solutions with 20.0 mL of 0.02 N sulfuric acid VS, and wash with three 5-mL portions of water. Combine the acid extract and washings in a beaker, and warm on a steam bath to expel any residual ether. Cool, add methyl red TS, and titrate the excess acid with 0.02 N sodium hydroxide VS (see Residual Titrations under Titrimetry 541). Each mL of 0.02 N sulfuric acid is equivalent to 6.256 mg of C17H17NO2·HCl·½H2O.
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Topic/Question Contact Expert Committee
Monograph Elena Gonikberg, Ph.D.
Senior Scientist
1-301-816-8251		 (MDGRE05) Monograph Development-Gastrointestinal Renal and Endocrine
Reference Standards Lili Wang, Technical Services Scientist
1-301-816-8129
RSTech@usp.org
701 Margareth R.C. Marques, Ph.D.
Senior Scientist
1-301-816-8106		 (BPC05) Biopharmaceutics05
USP32–NF27 Page 1573