RESUMEN
The chiral separation of an M3 antagonist was investigated using capillary electrophoresis (CE) with various sulfated cyclodextrins and by reversed-phase liquid chromatography with derivatized cellulose, derivatized amylose, and two protein stationary phases. Operational parameters for each technique, such as the concentration of the chiral selectors, background electrolyte (or mobile phase) pH and type, organic modifiers, injection mode and temperature were varied in order to achieve a desired elution order and to meet a 0.1% limit of quantitation (LOQ) criteria. Based on the advantages and disadvantages of each technique, a practical CE method using sulfated gamma-cyclodextrin was selected. The method was validated in terms of linearity, LOQ, accuracy, ruggedness and precision.
Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Electroforesis Capilar/métodos , Antagonistas Muscarínicos/aislamiento & purificación , Tampones (Química) , Concentración de Iones de Hidrógeno , Antagonistas Muscarínicos/química , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Estereoisomerismo , TemperaturaRESUMEN
A practical chiral capillary electrophoresis method using randomly sulfated beta-cyclodextrin was developed for the quantitative determination of the chiral purity of a pharmaceutical compound. A systematic method development approach was conducted by modifying selected parameters such as the concentration of the chiral selectors, buffer pH, organic modifiers, buffer concentrations and type, temperature and applied voltage. The results of the investigation permitted an improved understanding of the separation mechanism. Two facile strategies for the reversal of the enantiomer elution order are also described. The optimized method was validated in terms of variability of the chiral selector, linearity, sensitivity, accuracy, recovery, ruggedness, and precision.
Asunto(s)
Ciclodextrinas/química , Electroforesis Capilar/métodos , Preparaciones Farmacéuticas/aislamiento & purificación , beta-Ciclodextrinas , Tampones (Química) , Concentración de Iones de Hidrógeno , Preparaciones Farmacéuticas/química , Reproducibilidad de los Resultados , Estereoisomerismo , Ácidos Sulfúricos/química , TemperaturaRESUMEN
The separation of five positional isomers from 3,4-difluorophenylacetic acid was investigated using normal- and reversed-phase high-performance liquid chromatography, capillary zone electrophoresis, gas chromatography and supercritical fluid chromatography. Operating parameters of each technique, such as temperature, type of stationary phase, mobile phase pH, ionic strength, organic modifiers and additives were varied in order to elucidate the separation mechanisms. Based on the advantages and disadvantages of each methodology, a simple and practical RPLC method was selected. The method was validated in terms of linearity, limit of detection, accuracy, recovery, ruggedness and precision.
