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

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 mu M with a low detection limit (0.038 mu M), high selectivity, good sensitivity (0.4557 mu A/mu M cm(2)) and repeatability. Further, the suggested sensor was successfully employed for the determination of STLHC in real samples with suitable recovery values.