A Point-of-Care High-Throughput Biosensing System of Home Monitoring for CRC Postoperative Recurrence by Detecting CEA, MicroRNA-21, and IL-6

Objective Approximately 30% of stage II and 70% of stage III colorectal cancer (CRC) patients suffer postoperative recurrence owing to delayed diagnosis. However, existing diagnostic approaches, particularly electrochemical biosensors, face challenges including poor diagnostic accuracy in single-biomarker analysis, cross-reactivity in multiplex detection, and the absence of long-term home monitoring device.Methods This study introduced a portable point-of-care testing (POCT) biosensing system integrating a 256-channel microelectrode array (MEA) sensor for at-home detection of CRC recurrence biomarkers-carcinoembryonic antigen (CEA), microRNA-21 (miR-21), and interleukin-6 (IL-6).Results These sensors exhibited ultra-high sensitivity of 21.47 nA/lg(ng/mL), 26.50 nA/lg(pM), 15.72 nA/lg(ng/mL) for CEA, miR-21, and IL-6. Clinical validation showed strong concordance with conventional assays (ELISA and RT-qPCR), with correlation coefficients of 0.9809, 0.9998, and 0.9950.