Aptamer‐Based Electrochemical Point‐of‐Care Tests: Signal Design to Clinical Readiness

Aptamer‐based electrochemical biosensors have emerged as powerful platforms for point‐of‐care diagnostics by combining the molecular recognition precision of nucleic acid aptamers with the rapid and portable nature of electrochemical detection. This review critically examines how electrochemical signal‐transduction strategies translate aptamer–target interactions into measurable outputs and assesses their readiness for clinical implementation. Diverse signal designs are analyzed with respect to sensitivity, reproducibility, and suitability for miniaturized, reagent‐free testing. Representative applications in infectious‐disease diagnosis, cancer biomarker detection, cardiac and metabolic monitoring, and therapeutic drug measurement demonstrate that aptamer sensors can match or surpass current laboratory assays in analytical performance. Nevertheless, challenges remain in achieving stability in biological matrices, mitigating surface fouling, and ensuring large‐scale manufacturing and regulatory validation. Advances in chemical modifications, antifouling surface engineering, and flexible device architectures, including wearable and implantable formats, are progressively overcoming these barriers. The review also contrasts aptamers with antibodies to highlight niches where aptamer sensors provide unique advantages, such as continuous in vivo monitoring and rapid adaptation to emerging biomarkers. Overall, electrochemical aptamer sensors are approaching a transformative threshold from laboratory innovation to practical clinical diagnostics, marking a critical intersection between biotechnology and electronic sensing that may redefine the future of personalized and decentralized healthcare.