Modified screen-printed electrodes for determination of imipramine

Imipramine (Imi) is a tricyclic antidepressant drug, which is the most effective drug presently available for the treatment of depression and other psychiatric disorders by blocking the reuptake of norepinephrine at nerve terminals [1]. To enable its clinical applications to achieve optimum therapeutic effects and minimize side effects, analytical method with high sensitivity and free from interference is needed [2]. Many methods for the determination of Imi have been developed using techniques such as high performance liquid chromatography, gas chromatography, spectrophotometry, electrochemical analysis, chemometrics and capillary electrophoresis. Electrochemical methods are more desirable than other techniques because they are convenient and low cost. The screen-printed electrodes (SPEs) have been designed especially for miniaturization of electrochemical analytical systems [3]. SPEs are highly-versatile, easy to use, cost-effective analytical tools, also suitable to miniaturization. Furthermore, a screen printed electrode avoids the cleaning process, unlike conventional electrodes such as a glassy carbon electrode (GCE). In order to improve their electrochemical performance, SPEs have been modified with nano sized materials. The modified electrode has good electro catalytic activity, sensitivity, and selectivity; it has also a low detection limit compared to unmodified electrodes. In the present work, we synthesized magnetic core-shell manganese ferrite nanoparticles (MCSNP) and screen printed electrodes were modified with MCSNP. The electrochemical characterization of the modified electrodes was carried out by cyclic voltammetry, chronoamperometry and square wave voltammetry. Under optimized conditions, square wave voltammetry exhibited linear dynamic ranges from 1.0×10-6 – 2.0×10-4 M with detection limit of 1.8×10-7 M. The modified electrode exhibited excellent accuracy and precision, the relative standard deviation was less than 4%. Finally, the modified electrode was successfully used to accurately detect the content of Imi in real samples.