Xifeng Dou, Wenqing Geng, Rong Tan, Hao Peng, Yifeng Tu
An electrochemiluminescent (ECL) immunosensing strategy developed based on a gold nanoparticle-decorated UiO-66 composite (AuNPs@UiO-66) for the sensitive detection of proteins is reported. Benefiting from the synergistic effect between UiO-66 and AuNPs, the nanocomposite exhibits amplified luminol ECL due to specific surface area, fast electron-transfer, and catalytic activity toward the yielding of reactive oxygen species (ROSs). Meanwhile, the AuNPs provide favorable conditions for antibody immobilization to realize the specific sensing performance. The formation of immune-complexes leads to increasing steric hindrance of probe and interfacial electron-transfer resistance, resulting in decreased ECL emission. Under optimized conditions, the immunosensor for Talin-1 exhibits a linear range of 5-1000 pg·mL-1 with a detection limit of 1.25 pg·mL-1, while that for Talin-2 shows a linear range of 1-800 pg·mL-1 with a detection limit of 0.628 pg·mL-1. The proposed sensors have been successfully applied to human serum sample detection with satisfactory recoveries, indicating its reliability in complex biological matrices.