Application of Fe(III)-exchanged clinoptilolite/graphite nanocomposite for electrochemical sensing of amitriptyline

Abstract

Abstract This paper proposes a novel, ecofriendly voltammetric sensor for sensitive and selective amitriptyline (AMT) determination, based on glassy carbon electrode (GCE) surface modification by Fe3+ exchanged zeolite – clinoptilolite (FeZ) and graphite (G). The morphology and electrochemical properties of FeZ-G/GCE were investigated by X-ray powder diffraction (XRD), energy dispersion spectroscopy (EDS), scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The developed sensor showed improved catalytic activity and remarkable current increase for both model redox probe [Fe(CN)6]3-\\4- and AMT, in comparison to bare GCE and graphite modified G/GCE. In the analytical investigation of AMT using differential pulse voltammetry (DPV), the FeZ-G/GCE exhibited linear response in concentration ranges of 0.5 – 50.0 and 50.0 – 250.0 µmol L-1 with detection limit of 0.22 µmol L-1. The proposed sensor was successfully applied for the determination of amitriptyline in pharmaceutical, environmental water and urine samples with recovery of 95.5 – 99.2%.