Research On The Construction And Properties Of Glucose Sensors Under Oxygen-restrictive Condition

Glucose detection plays an important role in monitoring and controlling diabetes.The first-generation enzyme glucose sensor has been widely used in the detection of blood glucose due to its high selectivity,good biocompatibility and easy miniaturization.However,the problem of its high dependence on oxygen as the electron acceptor is very prominent.Designing new types of detection electrode,increasing the oxygen/substrate permeability ratio through the diffusion membrane,and optimizing the loading of enzymes are all effective solutions.Among them,using"oxygen-enriched"materials as the internal oxygen supply source can provide better optimization results.In this article,CeO₂ is selected as the"oxygen-enriched"material,relying on its special oxygen vacancy structure and through compounding other materials to improve the electrocatalytic activity of the system,in order to solve the oxygen dependence problem.Based on the above background,this article mainly has carried out specific work from the following aspects:1.The PVP stabilized Pt particles have been loaded into the synthesized CeO₂through adsorption method.The decorated sensor has a good linear response in the range of 0.1-1.6 m M glucose concentration under oxygen-rich conditions.The detection limit is 86μM,the sensitivity is 0.419μA m M^-1,and the sensor can also achieve a good detection effect for glucose in the concentration range of 0.1-1.0 m M under oxygen-restrictive condition.2.The CeO₂-Ce PO₄composites have been successfully synthesized by one-step reaction method.After combined with Ti O₂ nanoparticles,it can sensitively detect the corresponding concentration of glucose under oxygen-restrictive condition.The linear range is 0.1-1.7 m M,the detection limit is 17.1μM,and the sensitivity is 1.225μA m M^-1.At the same time,it can achieve a 0.1-1.0 m M glucose linear response under hypoxic conditions.The mechanism of the reaction system was verified through exploratory experiments and explained by solid-state electrochemical theory.3.The hexagonal flake-shaped Co（OH）₂materials have been synthesized through hydrothermal method,and then CeO₂ particles been loaded onto the Co（OH）₂ surface to prepare Co（OH）₂/CeO₂system.The modified sensor can achieve a good glucose response in the concentration range of 0.1-1.5 m M under oxygen-rich condition,with a detection limit of 92.1μM and a sensitivity of 0.25μA m M^-1.The detection effect under oxygen-restrictive condition remains to be promoted.