A Highly Receptive ZnO-Based Enzymatic Electrochemical Sensor for Glucose Sensing

The nano-structured Zinc Oxide (ZnO) has been synthesized by using hydrothermal method and modified via doping of Cobalt (Co), Iron (Fe), a mixture of Co and Fe (Co-Fe) for glucose sensing. The formations of pristine ZnO and doped ZnO have been confirmed by X-Ray diffraction (XRD), which suggests the incorporation of doping elements into the ZnO Matrix. The doped samples show a decrement in photoluminescence intensity in comparison to pristine ZnO, which is an indicative of the formation of competitive pathways for the recombination process. (Co-Fe) doped electrode shows better conductivity than other electrodes, which was later modified with Glucose Oxidase (GO(x)) for the application of electrochemical sensor. GOx modified (Co-Fe) doped ZnO sensor exhibits enhanced 2-fold sensitivity (32.2 mu A mM(-1)cm(-2)) in comparison to the pristine ZnO sensors following the linear range of 0-4 mM, response time 6.21 seconds and K-m(app) value of 0.054 mM. This sensor would be a potential candidate in clinical diagnosis, industry, and food science.

Automated summary

In this study, nano-structured Zinc Oxide (ZnO) was synthesized using the hydrothermal method and modified with Cobalt (Co), Iron (Fe), and a mixture of Co and Fe (Co-Fe) for glucose sensing. Doped samples showed reduced photoluminescence intensity compared to pristine ZnO, with (Co-Fe) doped electrodes demonstrating better conductivity. The GOx-modified (Co-Fe) doped ZnO sensor exhibited a 2-fold sensitivity enhancement, making it a potential candidate for clinical diagnosis, industry, and food science applications.