Development and validation of a CE method for the determination of common active ingredients in expectorant and decongestant syrups

GOMEZ, MARÍA ROXANA; SILVA MARÍA F.; OLSINA, ROBERTO

Simposio; 7mo Simposio Latinoamericano en Aplicaciones de la Electroforesis Capilar y Tecnología del Microchip en Biotecnología, Biomedicina, Biofarmacia e Industria, (LACE 2001); 2001

The commonly used syrup ingredients are basic nitrogenous compounds which include, among others, phenylpropanolamine, dextromethorphan, chlorpheniramine maleate, paracetamol, diphenhydramine and phenylephrine. The separation and determination of these products in dosage forms are complicated due to their similarities in some physical and chemical properties. Ultraviolet (UV-Vis) spectroscopy and high performance liquid chromatography (HPLC), are widely used to determine these compounds in preparations. These methods usually required extraction and sample clean- up procedures prior analysis. In addition, in HPLC, these basic drugs strongly interact with the stationary phases of the HPLC column causing peak asymmetry and low separation efficiency. The purpose of this study was to develop a MECK methodology for the separation of dextromethorphan, diphenhydramine and phenylephrine. Separations of these compounds were not obtained by CZE. MECK separation involves differences in hydrophobicity, hydrogen bonding, and charges, and such interactions are manipulated by surfactant concentration and organic modifiers. Therefore, methanol was used to enhance the resolution. The effects of buffer pHs, concentration of buffer, surfactant and organic modifiers, and sampling and separation modes were investigated. The best results were obtained with a BGE containing SDS-borate-phosphate-methanol.