ABSTRACT
A stability-indicating high-performance liquid chromatographic method was developed that can detect and quantitate low levels of the two most likely breakdown products of cuprimyxin. These degradation compounds, free myxin and its reduction product, can be determined in topical cream preparations in which cuprimyxin is formulated at the 0.5% (w/w) level. The method requires a simple two-step extraction, the addition of an internal standard, and chromatography on an amine-bonded column.
Subject(s)
Anti-Bacterial Agents/analysis , Copper/analysis , Drug Contamination , Chromatography, High Pressure Liquid , Ointments , Phenazines/analysisABSTRACT
A high-performance liquid chromatographic procedure was developed for the determination of isophenindamine in phenindamine tartrate bulk powder. The method employs a reversed-phase column and a mobile phase containing methanol, 0.001 M HNO3, and silver nitrate.
Subject(s)
Indenes/analysis , Pyridines/analysis , Chromatography, High Pressure Liquid , Drug Contamination , Powders , Spectrophotometry, UltravioletABSTRACT
Sensitive and efficient methods for sulfonamide determination as single entities and in combination with other drug substances in pharmaceutical dosage formulations were developed using high-performance liquid chromatography. These stability-indicating procedures involved a nitrile bonded phase column and nonaqueous mobile phases having diverse polarities. Sample potency was determined using peak height measurements. The methods may be used to determine trace sulfonamide quantities because detection limits are in the nanogram range.
Subject(s)
Sulfonamides/analysis , Chemical Phenomena , Chemistry , Chromatography, High Pressure Liquid , Drug Stability , MethodsABSTRACT
A high-performance liquid chromatographic method for esterified estrogens is described. By using a facile acid hydrolysis extraction procedure for the sample preparation, the compounds are chromatographed as their free phenolic forms. The separation of structurally similar compounds, such as equilenin, equilin, estrone, and estradiol, was achieved with a reversed-phase column and a methanol--water mobile phase. Several samples of bulk mixtures and tablets were assayed; the results compared favorably with those obtained using the USP XIX method. The method was rapid, and the detector response was linear over a wide concentration range. A relative standard deviation of +/- 5% indicates the reliability and accuracy of the proposed method.
