Simultaneous High Performance Liquid Chromatographic Determination of Theophylline and Ethylenediamine in Aminophylline Dosage Forms as Their Dansyl Derivatives

Abstract

A simple HPLC method has been developed for the assay of the components of aminophylline (theophylline: ethylenediamine 2:1) in solid and liquid dosage forms. Following the extraction of tablets into or the dilution of a liquid dosage form with water, the aqueous extract was reacted with dansyl chloride in an alkaline medium. The mixture of the dansyl derivatives of theophylline and ethylediamine was analyzed on an reversed phase μBondapak Cia column, using a methanol-water-acetic acid-triethylamine (60–65: 33–38: 1. 5:0. 5) mobile phase delivered at the rate of 1.5 mL/min, and a detection wavelength of 254 nm. In addition to exhibiting excellent accuracy and precision, the method yielded detector responses that were linearly related to concentrations of theophylline and ethylenediamine in aminophylline of up to 7 mg of theophylline, and of up to 10 mg