Dynamic-static coupled sensing of trace biomarkers by molecularly imprinted metal-organic frameworks

Accommodating target analytes within the pores of metal-organic frameworks (MOFs) to improve the sensing performance is an important but challenging task. Here, we report a novel molecular imprinting strategy to create target recognition sites in a tailored multicomponent MOF with the inter-ligand synergistic antenna effect to lanthanide ions, enabling selective recognition of trace biomarkers, which is critical to the early diagnosis of age-related diseases in blood samples with high sensitivity and ultralow limit of detection (LOD) of 69 nmol L−1. Compared with MOF-based sensors without imprinted recognition sites, the significantly enhanced sensing performance (both sensitivity and LOD) was attributed to a dynamic-static coupled sensing mechanism: the dynamic interactions involve concentrating the trace biomarkers at the imprinted recognition sites to enhance the sensing performance at ultralow concentration, and the static interactions are derived from electron/energy exchange between the molecularly imprinted MOF and the biomarker to govern the sensing performance. This work establishes a new molecular imprinting strategy to attain advanced materials for sensing trace bio-analytes.