摘要
Developing highly sensitive, non-invasive point-of-care (POC) devices for bladder cancer screening remains a critical challenge due to the high costs and low sensitivity of current clinical diagnostic methods. To overcome these limitations, this study reports the first-ever development of an ultra-sensitive electrochemical biosensor utilizing a screen-printed carbon electrode (SPCE) modified with a novel silver metal-organic framework integrated with a multilayer Niobium MXene composite (Ag-MOF@multilayer Nb-MXene). The key novelty lies in the synergistic interface of the Ag-MOF@multilayer Nb-MXene composite, which provides an exceptionally stable matrix and vastly accelerated charge-transfer capabilities for the high-density immobilization of cytokeratin-20 (CK-20) antibodies. Benefiting from this unique nano-architecture, the engineered biosensor demonstrated extraordinary analytical performance toward the target biomarker, exhibiting an exceptionally wide linear range from 10 fg/mL to 100 ng/mL and an unprecedentedly low limit of detection (LOD) of 0.001 pg/mL. Finally, the practical utility of this novel platform was successfully validated through the quantitative assessment of CK-20 expression levels in clinical human urine samples. This work introduces a powerful, high-performance strategy for non-invasive, early-stage bladder cancer diagnostics. © 2026 Elsevier Ltd.