Advances in Electrochemical Biosensors for COVID-19 Detection: Progress, Challenges, and Future Perspectives: A Review

The COVID-19 pandemic has led to over 770 million confirmed cases and nearly 7 million deaths globally as of early 2024, highlighting the urgent need for rapid, scalable, and accurate diagnostic tools. Electrochemical biosensors have gained increasing attention due to their miniaturization, affordability, and rapid response time. This review presents a structured and critical summary of electrochemical biosensing strategies applied to COVID-19 diagnostics, with an emphasis on genosensors, immunosensors, and label-free detection techniques. Key electrochemical methods—including voltammetry, amperometry, potentiometry, and electrochemical impedance spectroscopy—are discussed in the context of detecting viral proteins, nucleic acids, and antibodies. Notably, over 250 studies published since 2020 have demonstrated biosensors with detection limits as low as 1 fg/mL and response times under 10 min. The integration of nanomaterials such as graphene, carbon nanotubes, and transition metal dichalcogenides is reviewed for their role in enhancing signal output and biorecognition specificity. A bibliometric analysis of 779 articles (1985–2024) highlights global research trends and emerging areas. By consolidating these advancements and limitations, this review aims to guide researchers developing next-generation diagnostic tools for pandemic preparedness and infectious disease control.