Electrochemical biosensors: a novel approach for rapid and cost-effective hCG monitoring in gestational trophoblastic tumours.

Human chorionic gonadotropin (β-hCG) is a key biomarker for the diagnosis and monitoring of gestational trophoblastic disease (GTD). Current gold standard methods, such as chemiluminescent immunoassays and ELISA, are limited by high operational costs, long analysis times, and the requirements for centralized laboratory facilities, which restrict their accessibility, especially in resource-limited settings. As a promising alternative, electrochemical biosensors offer rapid, sensitive, selective, and cost-effective β-hCG detection, suitable for point-of-care applications. This review summarizes recent advances in the development of electrochemical β-hCG biosensors, with an emphasis on innovations in electrode engineering, interface design, biological recognition elements, and signal amplification strategies that significantly improve analytical performance, including detection limits and linear dynamic range. Considerable focus is assigned to biosensors that are capable of accurately measuring β-hCG at high concentrations, as required for effective clinical management of GTD. The review also discusses major challenges, such as prolonged stability, selectivity in complex biological matrices, reproducibility, and consistent measurement performance at clinically relevant high β-hCG levels. Finally, emerging trends such as miniaturization, microfluidic integration, and multiple detection are highlighted as promising directions to support real-time GTD monitoring.