Highly Sensitive ZnO/Au Nanosquare Arrays Electrode for Glucose Biosensing by Electrochemical and Optical Detection

Abstract

The fabrication of a ZnO/Au nanosquare-array electrode was successfully carried out for the detection of glucose concentration in biomedical applications. The fabrication of the ZnO/Au nanosquare array using an ultra-thin alumina mask (UTAM) based on the imprinted anodic aluminum oxide (AAO) template and the direct current (DC) sputtering method was able to produce a very well-ordered nanosquare arrangement with a side size of 300 nm and a thickness of 100 nm. Tests were done to evaluate the performance of the electrode by means of cyclic voltammetry (CV) which showed that the addition of glucose oxidase (GOx) increased the sensitivity of the electrode up to 1180 ± 116 μA mM−1cm−2, compared with its sensitivity prior to the addition of GOx of 188.34 ± 18.70 mA mM−1 cm−2. A iox/ired ratio equal to ~1 between the peaks of redox reactions was obtained for high (hyperglycemia), normal, and low (hypoglycemia) levels of glucose. The ZnO/Au nanosquare-array electrode was 7.54% more sensitive than the ZnO/Au thin-film electrode. Furthermore, finite-difference time-domain (FDTD) simulations and theoretical calculations of the energy density of the electric and magnetic fields produced by the ZnO/Au electrode were carried out and compared to the results of CV. From the results of CV, FDTD simulation, and theoretical calculations, it was confirmed that the ZnO/Au nanosquare array possessed a significant optical absorption and that the quantum effect from the nanosquare array resulted in a higher sensitivity than the thin film.

Desarrollo y repercusión de las películas delgadas en la actualidad

“…Las películas delgadas son la base de la eficiencia tecnológica de gran parte de los dispositivos electrónicos que, como se pueden depositar en diversas superficies, pueden ser utilizadas no sólo en el área de electrónica, sino también en la fabricación de luces LED (figura 1b), celdas solares (figura 1c), televisiones de película delgada (figura 1d) y en superficies antibacteriales, recubrimientos autolimpiantes, o en herramientas para proporcionar dureza en piezas mecánicas (Aida, et al, 2018, Wang, et al, 2021. Como ejemplo encontramos que los óxidos semiconductores de zinc (Zn), estaño (Sn), magnesio (Mg), entre otros, han sido utilizados en el desarrollo de sensores (Zulfa et al, 2023), transistores (Yan et al, 2022), detectores UV (Morari et al, 2022), etcétera. Mientras que las películas de sulfuro de cadmio (CdS) han sido utilizados en aplicaciones de almacenamiento de energía, principalmente en celdas solares (Nowsherwan et al, 2023).…”

Self-Supported 3D PtPdCu Nanowires Networks for Superior Glucose Electro-Oxidation Performance

“…Due to the synergistic action of the two materials, the bimetallic system can significantly increase the electrooxidation of glucose and reduce the influence of interference and toxic substances on the electrode. In addition, most bimetallic systems have received much attention due to their ability to operate in endosomatic pH environment, for instance, PtPb, PtRu, PtNi, PtPd, PtAu, AuCu, NiCu, etc., which have good catalytic performance for the electro-oxidation of small molecular [9][10][11][12][13][14][15][16][17][18]. However, the enzyme-free glucose sensor still faces some key problems, such as low sensitivity and unsatisfactory stability.…”

An efficient biosensor using a functionalized microneedle of Cu2O-based CoCu-LDH for glucose detection

“…14,15 Hence, non-enzymatic glucose electrochemical sensors opened up a new track by using direct redox reactions between glucose and electrodes. 16 Among the reported electrochemical sensors, modied electrodes with transition metal oxides (TMOs) such as ZnO, 17,18 NiO, 19 CuO, 20 Cu 2 O, 21,22 Co 3 N 23 and Co 3 O 4 (ref. 24) exhibit various advantages even beyond other noble metal or graphene sensors, especially the unique dorbital properties that enhance their electrocatalytic activity.…”