An Enzyme-free Glucose Sensor Based On Copper Oxide Nanomaterials

The rapid and accurate detection of glucose is very important for biomedicine,food,environmental monitoring and clinical diagnosis.Therefore,it is essential to establish a simple,fast and accurate glucose detection method.Electrochemical sensing technology is widely used in electrochemical analysis area because of its simple operation,low cost,rapid detection and high sensitivity.Enzyme-based electrochemical sensors,due to enzyme instability?affected by the environment,pH?,high prices,and complex manufacturing processes,have made their application somewhat limited.Therefore,the enzyme-free electrochemical sensing technology has emerged.Especially with the advancement of nanotechnology and nanomaterials,the enzyme-free electrochemical sensor based on the new nanomaterial has been greatly improved in selectivity and sensitivity.In this paper,the composite materials of cupric oxide,cuprous oxide and gold are used as research objects to improve the catalytic oxidation of glucose.The effects of copper oxides on the catalytic oxidation of glucose were studied in terms of structure and morphology.Therefore,Au@Cu₂O nanocomposites and feather-likeCuO nanomaterials were used to modify glassy carbon electrodes to prepare Au@Cu₂O/GCE and CuO/GCE enzyme-free glucose electrochemical sensors,and their electrochemical performances were preliminary explore as follows:Firstly,trisodium citrate was used to reduce chloroauric acid to obtain gold nanoparticles,and then Au@Cu₂O core-shell nanocomposite materials were obtained by a simple reduction method.The materials were characterized by TEM,EDS,XRD,Vis-UV,XPS,and some other techniques.The results showed that the Au@Cu₂O core-shell structure were successfully synthesized.The synthesized nanomaterials were modified on the surface of the treated glassy carbon electrode to prepare Au@Cu₂O/GC electrode.The sensor electrode can quickly and accurately detect glucose with a linear range of 0.05-2.0mM,detection limition of 0.16?M,and sensitivity of 715?A mM^-1cm^-2.At the same time,the anti-interference,stability and repeatability of the sensors were studied and used for the actual sample detection.A simple microwave method was used to synthesize feather-like copper oxide.This process was free of surfactants and environmentally friendly green synthesis.Some characterization techniques such as TEM,XRD and HRTEM were used to characterize the results.The synthesized material was modified onto the prepared glassy carbon electrode surface to prepare a CuO/GC electrode.The electrode has good catalytic oxidation ability to glucose and can quickly and accurately detect glucose,the linear range was 0.0005-2.4mM,the detection limition was 0.16?M,the sensitivity was 944.80?A mM^-11 cm^-2.The anti-interference,stability and repeatability of the sensor was tested and studied,and it was used for the actual sample detection and got better results.The experimental results showed that the structure and morphology of copper oxides will affect the catalytic oxidation of glucose.The enzyme-free electrochemical sensor constructed based on novel semiconductor nanomaterials with different structures and morphologies has high sensitivity and chemical response to glucose and has a good development prospect.