A Green-Emission Metal–Organic Framework-Based Nanoprobe for Imaging Dual Tumor Biomarkers in Living Cells

The
modular nature of metal–organic frameworks (MOFs) permits
their tunable structure and function for target application, such
as in biomedicine. Herein, a green-emission Zr­(IV)-MOF (BUT-88) was
constructed from a customized luminescent carbazolyl ligand. BUT-88
represents the first bcu-type MOF with both organic linker and metal
node in eight connections and shows medium-sized pores, rich accessible
linking sites, and good water stability and biocompatibility. In virtue
of these merits, BUT-88 was then fabricated into a MOF-based fluorescent
nanoprobe, drDNA-BUT-88. Using it, the live-cell imaging of dual tumor
biomarkers was achieved for the first time upon a MOF-based probe,
offering enhanced detection precision in early cancer diagnosis. Particularly,
the probe showed efficient ratiometric fluorescent sensing toward
the cytoplasmic biomarker microRNA-21, further improving the detection
accuracy at the cellular level. In this work, the elaborate combination
of MOF engineering and the fluorescent detection technique has contributed
a facile biosensing platform, unlocking more possibilities of MOF
chemistry.