Development of high performance liquid chromatography methods with charged aerosol detection for the determination of lincomycin, spectinomycin and its impurities in pharmaceutical products.

Novel and simple liquid chromatography methods with charged aerosol detection (LC-CAD) for simultaneous quantitation of lincomycin and spectinomycin and its related substances have been developed and tested. This type of analysis is complicated due to the different chromatographic behavior of these two agents and the lack of chromophores in spectinomycin complex. CAD seems to be a promising alternative to overcome these difficulties. It shows a consistent inter-analyte response, independent of chemical structure of an analyte. It also enables the direct quantification of related substances for which no reference standards were available, with good accuracy and precision. Chromatographic separations were achieved using a C18 Hypersil(®) Gold column, with mobile phases consisting of water, acetonitrile and trifluoroacetic acid. All impurities were identified using time-of-flight mass spectrometry with electrospray ionization. The developed methods have been successfully used in the routine quality control analysis of pharmaceutical preparations.