Metal–organic framework-based dual-mode biosensors: Mechanisms and applications

To address the growing complexity of detection scenarios, biosensing technology is transitioning from single-modal to dual-mode systems. Metal-organic frameworks (MOFs), with their high surface area, tunable pore structures, and multifunctional properties, have emerged as ideal substrates for dual-mode biosensors. Their advantages include: (1) precisely engineered coordination between metal nodes and ligands enables synergistic optical-electrochemical signal outputs; (2) intrinsic enzyme-like or photo/electrocatalytic activities (when present) can amplify detection signals through substrate conversion; (3) modular design allows simultaneous integration of signal transduction and, where applicable, catalytic functions, establishing a robust sensing synergy. This technology has been successfully applied in detecting biomolecules, pathogens, biotoxins, pesticides, heavy metals, and emerging contaminants. Current research focuses on structure-activity optimization, yet challenges remain, such as matrix interference and stability issues. Future efforts require interdisciplinary collaboration to develop intelligent MOFs, micro-nano integrated systems, and practical validation. This review systematically analyzes the synthetic strategies of MOFs for dual-mode biosensors, sensing mechanisms, current challenges, and future prospects, thereby providing theoretical and technical guidance for the design of high-precision biosensing platforms.