Negative Potential-Induced Growth of Surfactant-Free CuO Nanostructures on an Al–C Substrate: A Dual In-Line Sensor for Biomarkers of Diabetes and Oxidative Stress

Abstract

Identifying a non-enzymatic sensor electrocatalyst for the accurate determination of biomolecules is a paramount task. The weird morphology of the nanomaterial may exhibit the remarkable activity to enhance the sensitivity of the electrode, and hence, tuning the shape of the nanomaterials is one of the important criteria for electrochemical sensors. Thus, this study sought to fabricate a non-enzymatic sensor with different CuO morphologies by an eco-friendly and facile approach. Different surfactant-free CuO nanostructures were fabricated on the highly conductive flexible aluminum-carbide substrate for the electrochemical assessment of glucose and H2O2 in human fluids. The CuO nanostructures were initially electrodeposited at −0.1, −0.3, −0.5, and −0.7 V and then calcined in air at 120 °C for 2 h. Different CuO nanostructures with a polygonal and cactus-like morphology were observed in scanning electron microscopic images. The as-fabricated electrodes were also characterized by X-ray diffraction (XRD), Xray photoelectron spectroscopy, and electrochemical impedance spectroscopy analysis.Texture coefficients (TC) of different CuO nanostructures were calculated from XRD analysis, and the CuO nanostructures grown at −0.5 V exhibited the highest TC with their texture along the (022) plane. The electrodes grown with different CuO nanostructures exhibited shapedependent electrocatalytic activity against glucose and H2O2, and the cactus-like CuO nanostructures grown at −0.5 V showed superior electrochemical behavior compared to that of the other nanostructures by showing superior sensitivities of 3892.6 and 2015.7 μA mM-1 cm-2, respectively, against glucose and H2O2. In addition, the sensor grown with a cactus-like CuO nanostructure exhibited high selectivity, storage capability, and good practicability. This sensor proved to be practical by determining glucose and H2O2 levels in human fluids. It is believed that the proposed electrochemical sensor will have a strong impact in the dual in-line sensing of biomarkers in both biological and clinical fields in the near future.

Gold Nanospikes Formation on Screen-Printed Carbon Electrode through Electrodeposition Method for Non-Enzymatic Electrochemical Sensor

“…Meanwhile, the more negative the potential, the greater the reduction current produced. As a result, the reduced nanomaterial becomes denser due to the increased rate of the growth process for forming Au nanostructures [39]. These results indicate that the applied potential significantly affects the deposited Au morphology in the electrodeposition method.…”

Proton-Conductive and Electrochemical-Sensitive Sensing Behavior of a New Mn(II) Chain Coordination Polymer

“…A novel reported SOI-GO x working electrode can sense glucose linearly over a wide range of 1–15 mM . However, enzymatic electrochemical biosensors are often inconvenient to operate, expensive, and sensitive to external environments like pH, temperature, etc . , Alternatively, nonenzymatic electrochemical sensors have been developed due to their advantages like excellent sensitivity, seldom being influenced by the environment, stability, and quick response. , Nowadays, some transition-metal oxides, carbon materials, and transition metals have been widely applied as active electrode materials for nonenzymatic H 2 O 2 and NO 2 – electrochemical sensing. , However, inferior antitoxic ability and low stability limit their applications. To overcome these shortcomings, it is urgent to fabricate new electrode materials with satisfactory sensing performance for H 2 O 2 and NO 2 – .…”

“…14,15 Alternatively, nonenzymatic electrochemical sensors have been developed due to their advantages like excellent sensitivity, seldom being influenced by the environment, stability, and quick response. 16,17 Nowadays, some transition-metal oxides, carbon materials, and transition metals have been widely applied as active electrode materials for nonenzymatic H 2 O 2 and NO 2 − electrochemical sensing. 18,19 However, inferior antitoxic ability and low stability limit their applications.…”

Co3O4 Nanoparticles Uniformly Dispersed in Rational Porous Carbon Nano-Boxes for Significantly Enhanced Electrocatalytic Detection of H2O2 Released from Living Cells

“…Thus, non-enzymatic electrochemical sensors were proposed to overcome the limitations of natural enzyme sensing platforms [ 18 ]. Various nanomaterials have been used in H 2 O 2 sensors, including transition metals oxides (e.g., Fe 3 O 4 , Co 3 O 4 , NiO, CuO) [ 19 , 20 , 21 , 22 ]. Transition metals have multiple oxidation states.…”