A new micellar electrokinetic capillary chromatography method for separation of the components of the XXXX antibiotics.

@entity6743 @entity801 @entity2890 @entity7913 @entity4028 @entity11151 @entity20720 @entity4509 @entity43904 @entity5153 @entity33437 @entity33504 @entity3363 @entity12894
@entity4028 antibiotics are always a mixture of structurally related amino @entity3363 , which do not have a chromophore or fluorophore. The aim of the study was to find one method for evaluation of the components and impurities of the antibiotics. Derivatization with @entity20720 and @entity33437 is found to be appropriate for all antibiotics. The components of @entity801 (GM), @entity12894 , @entity5153 , @entity7913 , @entity4509 , and @entity2890 were tried to separate by means of micellar electrokinetic chromatography. The background electrolyte was composed of @entity33504 (100 mM, pH 10.0), @entity6743 (20 mM), and @entity11151 (15 mM). This method is valid for evaluation of GM, @entity7913 , and @entity2890 . It has to be improved for @entity4509 and @entity5153 . In addition, 46 bulk samples of GM of different manufacturer or pharmaceutical companies were investigated. Many samples were found to contain many minor products and different amounts. Beside different patterns of the main compounds GM C1, GM @entity43904 , GM C2a, and GM C2, many lots were found consisting of a substantial number of minor products. The appearance of a high number of minor products is always associated with the existence of @entity12894 , which is not found in "pure" samples. However, almost all samples met the requirements of the European Pharmacopoeia (EP) and United States Pharmacopoeia (USP).
