Identification—
Place a portion of finely powdered Tablets, equivalent to about 30 mg of clomiphene citrate, in a centrifuge tube containing about 30 mL of a 1 in 2 solution of methanol in 0.1 N hydrochloric acid. Insert the stopper, and place the tube in a water bath at about 37
for 15 minutes. Shake occasionally. Centrifuge, and place the clear supernatant in a separator. Extract with one 40-mL and two 25-mL portions of hexanes, and discard the extract. Render the aqueous solution alkaline with 1 N sodium hydroxide, and extract the precipitated base with one 50-mL and two 25-mL portions of hexanes. Wash the combined extracts with two portions of water. Dry the extract with anhydrous sodium sulfate, and remove the hexanes by evaporation under reduced pressure. Add about 1.0 mL of carbon disulfide to the residue, and dissolve. Determine the absorption spectra of the test solution and of a Standard solution of
USP Clomiphene Citrate RS, similarly prepared, as directed under
Identification—Organic Nitrogenous Bases 
181
.
Dissolution 711—
Medium:
water; 900 mL.
Apparatus 1:
100 rpm.
Time:
30 minutes.
Procedure—
Determine the amount of C
26H
28ClNO·C
6H
8O
7 dissolved from UV absorbances at the wavelength of maximum absorbance at about 232 nm of filtered portions of the solution under test, suitably diluted with 0.1 N hydrochloric acid, in comparison with a Standard solution having a known concentration of
USP Clomiphene Citrate RS in the same medium.
Tolerances—
Not less than 75% (Q) of the labeled amount of C26H28ClNO·C6H8O7 is dissolved in 30 minutes.
Assay—
Mobile phase, Standard preparation, System suitability solution, and Chromatographic system—
Proceed as directed in the
Assay under
Clomiphene Citrate.
Assay preparation—
Weigh and finely powder not less than 20 Tablets. Transfer an accurately weighed portion of the powder, equivalent to about 50 mg of clomiphene citrate, to a 100-mL volumetric flask. Add about 50 mL of Mobile phase, and stir using a magnetic bar for about 30 minutes. Remove the magnetic bar from the flask, dilute with Mobile phase to volume, mix, and filter. Transfer 10.0 mL of this solution to a 100-mL volumetric flask, dilute with Mobile phase to volume, mix, and filter, discarding the first 10 mL. [NOTE—This solution is stable for at least 24 hours.]
Procedure—
Separately inject equal volumes (about 50 µL) of the
Standard preparation and the
Assay preparation into the chromatograph, record the chromatograms, and measure the responses for the major peaks. Calculate the quantity, in mg, of C
26H
28ClNO·C
6H
8O
7 in the portion of Tablets taken by the formula:
1000C(rU / rS),
in which
C is the concentration, in mg per mL, of
USP Clomiphene Citrate RS in the
Standard preparation; and
rU and
rS are the peak responses obtained from the
Assay preparation and the
Standard preparation, respectively.
