A biosensor is an analytical device that contains a biological component with a selective response to an analyte, upon which a signal proportional to the analyte concentration in the sample is generated on the transducer. For the determination of glucose in various samples, electrochemical biosensors based on the enzyme glucose oxidase (GOx) are most commonly used. GOx catalyzes the oxidation of glucose to gluconolactone and hydrogen peroxide. During the reaction, an electron flow occurs, leading to a change in electric current that is detected by the electrode. Proper functioning of the biosensor with adequate repeatability, sensitivity, and durability is crucial, and appropriate enzyme immobilization plays a significant role. In my thesis, I conducted a literature review and presented various immobilization techniques and materials in glucose biosensors with GOx. The most widely used techniques for immobilizing GOx are covalent binding to the electrode surface, which is strong and durable but can affect the enzyme's structure and activity, and entrapment or encapsulation in polymeric matrices, which protect the enzyme from external influences but may lead to permeability issues. The most commonly used materials for electrodes in biosensors are inert metals and carbon-based materials, and electrodes are often modified with nanomaterials or polymeric films to enhance sensor performance. The main directions for the further development of glucose biosensors are aimed at improving enzyme stability, biosensor lifespan, and reducing the impact of interferences.
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