| Abstract: | Abstract The oxidation of theophylline was studied at a carbon paste electrode in the presence of cetyltrimethyl ammonium bromide by cyclic and differential pulse voltammetry. The results indicated that the electrochemical responses of theophylline are apparently improved by cetyltrimethyl ammonium bromide, due to the enhanced accumulation of theophylline at carbon paste electrode surface. Under optimal conditions the peak current was proportional to theophylline concentration in the range of 8.0 × 10?7 to 2.0 × 10?4 M with a detection limit of 1.85 × 10?7 M by differential pulse voltammetry. The proposed method was applied to the determination of theophylline in tablet and urine samples. |
