Simultaneous Determination of Dextromethorphan, Diphenhydramine and Phenylephrine in Expectorant and Decongestant Syrups by Capillary Electrophoresis

M. ROXANA GÓMEZ; ROBERTO A. OLSINA; L. DANTE MARTÍNEZ; M. FERNANDA SILVA

JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS

Elsevier

Año: 2002 vol. 30 p. 791 - 799

0731-7085

The separation of basic nitrogenous compounds commonly used as active ingredients in cold medicine formulations by micellar electrokinetic capillary chromatography and capillary zone electrophoresis with direct absorptiometric detection was investigated. The type and composition of the background electrolyte (BGE) were investigated with respect to separation selectivity and BGE stability. BGE of 10 mM sodium dihydrogenphosphate?sodium tetraborate buffer containing 10 mM SDS and 10% acetonitrile, pH 9.0 was found to be optimal. Dextromethorphan hydrobhromide, diphenhydramine hydrochloride and phenylephrine hydrochloride were baseline-separated in less than 11 min, giving separation efficiencies of up to 494,000 theoretical plates, reproducibility of corrected peaks areas below 3% relative standard deviation and concentration detection limits from 2.5 to 5.5 g ml−1. Detection was performed at 196 and 214 nm.g ml−1. Detection was performed at 196 and 214 nm.