A Novel Two-Electrode Microchip-Based Electrochemiluminescence Point-of-Care Testing System for Rapid and Highly Sensitive Multiple Biomarkers Analysis

Point-of-care testing (PoCT) method is suitable for rapid detection and daily monitoring of various acute diseases, which can effectively improve patients' survival rates. Current lateral flow assay (LFA)-based PoCT systems, with insufficient sensitivity, cannot meet the simultaneous detection requirements of rare multiple biomarkers. Therefore, we developed an electrochemiluminescence (ECL) microchip-based PoCT system, realizing rapid and highly sensitive detection of multiple biomarkers. This microchip incorporated specific aptamer probes assembled working electrode (WE) array and a shared counting electrode; thus forming a two-electrode-based detection unit for initiating Ru(bpy)(3)(2+) tripropylamine (TPrA)-based ECL reaction. Integrated with photomultiplier tube (PMT) and a constant transient potential (TP) model, the PoCT system was capable of sensitively detecting three acute myocardial infarction (AMI) biomarkers-cardiac troponin I (cTnI), myoglobin (Myo), and creatine kinase MB (CK-MB)-on a single microchip within just 20 min. The system exhibited an excellent detection limit of 0.25, 0.05, and 5 pg/mL for cTnI, Myo, and CK-MB, in a wide linear range of 1- 1 mu g/mL, 0.1-10 ng/mL, and 10- 1 mu g/mL, respectively. Furthermore, the analysis of AMI biomarkers in mixture and serum samples was conducted with high sensitivity and specificity, as well as low crosstalk. The platform synergized high sensitivity of ECL with the multiplexing of microchip, thereby holding tremendous potential for application in PoCT.