Batch-Injection Amperometric Determination of Caffeine and Theophylline on an Electrode Modified by Carbon Nanotubes and Ruthenium Oxides

Abstract

© 2020, Pleiades Publishing, Ltd. Abstract: A procedure for the batch-injection amperometric determination of caffeine and theophylline using a screen-printed electrode modified with a composite based on ruthenium oxides and functionalized single-walled carbon nanotubes was developed. The effect of the parameters of the batch-injection system on the recorded signals was studied; the optimal detection conditions were selected. The analytical signal linearly depends on the concentration of compounds on the logarithmic coordinates in the range from 5 × 10–9 to 5 × 10–3 M. A possibility of the simultaneous batch-injection amperometric determination of caffeine and theophylline on a modified double screen-printed electrode is demonstrated. The proposed method for the determination of caffeine and theophylline was tested in the analysis of pharmaceutical preparations.