Recent advances in electrochemical biosensors for the determination of biomolecules on modified and unmodified electrodes

Electrochemical sensors are a class of sensors in which the electrode is the transducer element. In this type of sensor, an electrode is a critical component employed as a solid support for immobilizing biomolecules and electron movement. The material, fabrication approach, and design affect the electrode’s structure and properties, which ultimately determine the biosensor’s performance, including sensitivity, selectivity, limit of detection, and dynamic range. They also influence the biosensor’s cost, manufacturability, disposability, and measurement capabilities. This review article describes recent advances in using non-modified and modified electrodes as support in electrochemical biosensors for the determination of biomolecules. It summarizes recent work on modifying electrodes using carbonaceous materials, conducting polymers, MXenes, and transition metal oxide nanomaterials. It also focuses on current techniques, types of materials, designs, simulation studies, and fabrication methods on unmodified and modified electrodes. Lastly, challenges in electrochemical sensors were identified, and future directions were presented comprehensively.