Energy-Transfer Metal–Organic Nanoprobe for Ratiometric Sensing with Dual Response to Peroxynitrite and Hypochlorite

Abstract

An energy-transfer metal–organic nanoprobe is designed for ratiometric sensing with dual response to both peroxynitrite (ONOO – ) and hypochlorite (ClO – ). Here, a nanoscale metal–organic framework (NMOF) acts as the energy donor and molecular probe as the acceptor to construct a Förster resonance energy transfer (FRET) nanosystem. Biocompatible dextran conveniently binds to the NMOF surface through multiple weak coordination interactions to improve water dispersibility and cell uptake. Dextran can also coordinate with the molecular probe with arylboronic acid group, which enables the convenient grafting of molecular probes to the NMOF surface to construct energy-transfer nanoprobes. Because of efficient FRET, the bright blue fluorescence of NMOF is quenched, whereas red emission from the acceptor is enhanced. Upon reacting with ONOO – , the probe departs from NMOF and the fluorescence of NMOF is recovered because of the interruption of FRET. When reacting with ClO – , the phenothiazine moiety in the molecular probe is oxidized into phenothiazine-5-oxide, which leads to more efficient energy transfer and the fluorescence shifts from red to orange. The nanoprobes are also successfully applied to the detection of ONOO – and ClO – in living cells.

Photoluminescent sea urchin-shaped carbon-nanobranched polymers as nanoprobes for the selective and sensitive assay of hypochlorite

“…After treatment with ClO − , the electron-donating thioether moiety was converted to an electron-deficient sulfoxide moiety by oxidation. 42 Thereby, the PCT process was dramatically inhibited, leading to a high-contrast FL blue shift. As shown in Fig.…”

Nanoscale Metal-Organic Frameworks as Fluorescence Sensors for Food Safety

“…MOFs are a class of hybrid porous materials formed by organic ligand and metal ions [ 10 , 11 ]. Owing to the abundant combination of metals and organic ligands, high surface areas, and numerous adjustable pores, MOFs have been applied for a variety of fields [ 12 ], such as energy storage [ 13 ], gas storage [ 14 ], catalysis [ 15 ], biomedical imaging and drug delivery [ 16 ], separation [ 17 ], adsorption [ 18 ], sensing [ 19 , 20 , 21 , 22 , 23 ], etc. However, bulk-size MOFs for use as fluorescence sensors suffer from some shortcomings like slow signal response, poor dispersity as well as stability and that application is difficult in the liquid phase [ 24 , 25 ].…”

Coordination-Directed Assembly of Luminescent Semiconducting Oligomers and Weak Interaction-Induced Morphology Transformation

“…The modified oligomers can significantly improve the performance of various applications, many researchers introduce functional groups or special atoms which could stimulate the response to modify the functionalized oligomers, thus widening the application filed. 5−7 For example, some of the modified oligomers were introduced to the luminescent or halogen-containing functional groups and applied in light-harvesting, organic field effect transistors, and sensors. 8−13…”

“…In recent years, the functionalized organic luminescent polymers and oligomers, especially luminescent semiconducting oligomers (LSOs) have drawn increasing attention as they have presented great potentials in opto-electronics. − These kinds of evolving materials always have known chemical structures and modifiable molecular units, they can be modified by a variety of methods depending on the demand for functions. The modified oligomers can significantly improve the performance of various applications, many researchers introduce functional groups or special atoms which could stimulate the response to modify the functionalized oligomers, thus widening the application filed. − For example, some of the modified oligomers were introduced to the luminescent or halogen-containing functional groups and applied in light-harvesting, organic field effect transistors, and sensors. − …”

“…Our previous work revealed that the modification of ligands with long-alkyl chains can significantly improve the colloidal stability of coordination polymers. By proper selection of metal ions, nanowires, nanospheres, and nanodisks could be facilely prepared, which were applied in light harvesting and sensors. ,, In this work, we focus on the coordination-directed assembly and investigate how weak interactions affect the self-assembly behavior. We introduced two novel fluorescent ligands OFBB and OFBT bearing two carboxylic acid groups (Scheme a,b), which can coordinate with metal ions to form polymeric products.…”