A ratiometric fluorescent nanoprobe for adenosine triphosphate sensing in living cells, based on silica nanoparticles and a DNA-functionalized hybrid hydrogel.

No abstract

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.

A novel surface-enhanced Raman scattering (SERS) assay is demonstrated by developing a cross strand-displacement amplification (CSDA) method to enhance the SERS signals. Highly sensitive and selective detection of any single-stranded DNA is achieved and an aptasensor for proteins is constructed.