Abstract

The present study was designed to synthesize lanthanum doped fern-like CuO nanoleaves (La3+-CuO fern-like nanoleaves), which were characterized by Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction, scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) techniques. The mixing of fern-like La3+-CuO nanoleaves and multi-walled carbon nanotubes (MWCNTs) modified carbon paste electrode (CPE) was used to construct La3+-CuO/MVVCNTs/CPE. Subsequently, the experiments were continued by studying the electrochemical oxidation of morphine on fabricated La3+-CuO/MWCNTs/CPE so that the oxidation peak potential was found at 330 my, meaning about 260 mV decrease of the overpotential than that on the traditional CPE, and about 4.9 times increase was observed for the oxidation peak current. A sensitive analytical approach was obtained by differential pulse voltammetry in accordance with the relationship between the oxidation peak current and the morphine concentration. The linear range of 0.05 to 325.0 mu M was obtained for morphine determination with the 3 sigma detection limit of 8.0 nM. Moreover, this sensor proved favorable to simultaneously determine morphine and dopamine. The presence of morphine was also detected in real samples using our introduced approach as a selective, simple and precise electrochemical sensor. (C) 2019 Published by Elsevier B.V.