» Bromocriptine Mesylate contains not less than 98.0 percent and not more than 102.0 percent of C32H40BrN5 O5·CH4SO3, calculated on the dried basis.
Packaging and storage Preserve in tight, light-resistant containers, in a cold place.
USP Reference standards 11
USP Bromocriptine Mesylate RS.
A: Infrared Absorption 197M: undried.
B: Ultraviolet Absorption 197U
Solution: 50 µg per mL.
Medium: 0.1 M methanolic methanesulfonic acid.
Color of solution 631
Matching solutions Prepare three solutions, A, B, and C, containing, respectively, the following parts of cobaltous chloride CS, ferric chloride CS, cupric sulfate CS, and dilute hydrochloric acid (1 in 40):
Procedure Prepare a test solution by dissolving 100 mg of Bromocriptine Mesylate in 10.0 mL of methanol, and compare this solution with 10-mL portions of the Matching solutions in suitable matched tubes: the solution is clear and not darker in color than Matching solutions A, B, and C.
Specific rotation 781S: between +95 and +105.
Test solution: 10 mg per mL, in a mixture of methylene chloride and methanol (1:1).
Loss on drying (see Thermal Analysis 891) Determine the percentage of volatile substances by thermogravimetric analysis on an appropriately calibrated instrument, using about 10 mg of Bromocriptine Mesylate, accurately weighed. Heat the specimen under test at the rate of 10 per minute in an atmosphere of nitrogen at a flow rate of about 45 mL per minute. Record the thermogram from ambient temperature to 160: it loses not more than 4.0% of its weight.
Residue on ignition 281: not more than 0.1%.
Heavy metals, Method II 231: 0.002%.
Limit of methanesulfonic acid content Transfer about 400 mg, accurately weighed, to a titration vessel, dissolve in 70 mL of methanol, and titrate under nitrogen with 0.1 N methanolic potassium hydroxide VS, determining the endpoint potentiometrically. Perform a blank determination, and make any necessary correction. Each mL of 0.1 N methanolic potassium hydroxide is equivalent to 9.61 mg of CH3SO3H. Not less than 12.5% and not more than 13.4% of CH3SO3H, calculated on the dried basis, is found.
Citrate buffer Prepare a 0.1 N citric acid solution, adjust with hydrochloric acid to a pH of 2.0, and mix.
Diluting solution Prepare a mixture of methanol and Citrate buffer (1:1).
Solution A Mix 57 mL of 0.01 M phosphate buffer having a pH of 7.0 and 43 mL of acetonitrile.
Solution B Mix 40 mL of 0.01 M phosphate buffer having a pH of 7.0 and 60 mL of acetonitrile.
Mobile phase Use variable mixtures of Solution A and Solution B as directed for Chromatographic system. Make adjustments if necessary (see System Suitability under Chromatography 621).
System suitability solution Dissolve accurately weighed quantities of -ergocryptine and Bromocriptine Mesylate in Diluting solution to obtain a solution containing about 2.0 mg of each per mL.
Standard solution Dissolve an accurately weighed quantity of USP Bromocriptine Mesylate RS in methanol, dilute quantitatively with an equal volume of Citrate buffer, and dilute quantitatively, and stepwise if necessary, with Diluting solution to obtain a solution having a known concentration of about 4.6 µg per mL.
Test solution Transfer about 46 mg of Bromocriptine Mesylate, accurately weighed, to a 10-mL volumetric flask, dissolve in 5.0 mL of methanol, dilute with Citrate buffer to volume, and mix.
Chromatographic system (see Chromatography 621) The liquid chromatograph is equipped with a 300-nm detector and a 4.6-mm × 15-cm column that contains 3-µm packing L1. The flow rate is about 2 mL per minute. The chromatograph is programmed as follows.
Procedure Separately inject equal volumes (about 20 µL) of the Standard solution and the Test solution into the chromatograph, record the chromatograms, and measure all of the peak responses. Calculate the percentage of each impurity in the portion of Bromocriptine Mesylate taken by the formula:
1000F(C/W)(ri / rS)in which F, the relative response factor, is equal to 0.7 for any peaks eluting at a relative retention time of about 0.9 or less, and is equal to 1.0 for all other peaks; C is the concentration, in mg per mL, of USP Bromocriptine Mesylate RS in the Standard solution; W is the weight, in mg, of Bromocriptine Mesylate taken for the Test solution; ri is the peak response for each impurity obtained from the Test solution; and rS is the peak response for bromocriptine obtained from the Standard solution: not more than 0.4% of bromcriptinin is found; not more than 0.1% of any individual impurity is found; and not more than 1.0% of total impurities is found.
Assay Transfer about 600 mg of Bromocriptine Mesylate, accurately weighed, to a titration vessel, dissolve in 80 mL of a mixture of acetic anhydride and glacial acetic acid (7:1), and titrate with 0.1 N perchloric acid VS, determining the endpoint potentiometrically. Perform a blank determination, and make any necessary correction. Each mL of 0.1 N perchloric acid is equivalent to 75.07 mg of C32H40BrN5O5·CH4SO3.
Auxiliary Information Please check for your question in the FAQs before contacting USP.Chromatographic Column
USP32NF27 Page 1707Pharmacopeial Forum: Volume No. 31(5) Page 1346
Chromatographic columns text is not derived from, and not part of, USP 32 or NF 27.