Direct electrochemical synthesis of the copper based metal-organic framework on/in the heteroatoms doped graphene/pencil graphite electrode: Highly sensitive and selective electrochemical sensor for sertraline hydrochloride

Abstract

Abstract In this study, a simple and innovative electrochemical method was utilized for the synthesis of the copper based metal-organic framework (Cu-MOF)/sulfur and nitrogen co-doped graphene (SNDGr) nanocomposite on the pencil graphite electrode (PGE) and developing of an electrochemical sensor for determination of sertraline hydrochloride (STLHC); an antidepressant drug. Firstly, the SNDGr was simply synthesized through the electrochemical exfoliation of PGE by using potentiostatic procedure in the mixture solution of melamine and ammonium sulfate. Thereafter, the Cu-MOF was also electrochemically deposited on/in SNDGr/PGE using chronoamperometry technique. The as-fabricated modified electrode (Cu-MOF/SNDGr/PGE) was characterized through relevant instrumental methods (scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray powder diffraction, and electrochemical techniques). The designed modified electrode exhibited excellent electrocatalytic activity for the oxidation of STLHC compared with bare PGE, SNDGr/PGE and Cu-MOF/PGE due to its high specific surface area, high conductivity and fast charge transfer ability of the nanocomposite. The experimental results demonstrated that the present modified electrode has a promising potential as a stable and efficient electrochemical sensor for determination of STLHC. Under the optimized experimental condition, the designed sensor responds efficiently to STLHC over the concentration range of 0.05 to 2.67 µM with a low detection limit (0.038 μM), high selectivity, good sensitivity (0.4557 μA/μM cm2) and repeatability. Further, the suggested sensor was successfully employed for the determination of STLHC in real samples with suitable recovery values.