An Amide-Containing Metal–Organic Tetrahedron Responding to a Spin-Trapping Reaction in a Fluorescent Enhancement Manner for Biological Imaging of NO in Living Cells

Abstract

Metal-organic polyhedra represent a unique class of functional molecular containers that display interesting molecular recognition properties and fascinating reactivity reminiscent of the natural enzymes. By incorporating a triphenylamine moiety as a bright blue emitter, a robust cerium-based tetrahedron was developed as a luminescent detector of nitronyl nitroxide (PTIO), a specific spin-labeling nitric oxide (NO) trapper. The tetrahedron encapsulates molecules of NO and PTIO within the cavity to prompt the spin-trapping reaction and transforms the normal EPR responses into a more sensitively luminescent signaling system with the limit of detection improved to 5 nM. Twelve-fold amide groups are also functionalized within the tetrahedron to modify the hydrophilic/lipophilic environment, ensuring the successful application of biological imaging in living cells.

Controllable Coordination Self‐Assembly Based on Flexible Tripodal Ligands: From Finite Metallocages to Infinite Polycatenanes Step by Step

“…[55,56] As shown in Figure 22a, 4 ] 121 can recognize different guest molecules. As described above, due to the highly changeable nature of flexible tripodal ligands, many different types of metallocages such as M 3 L 2 , M 6 L 8 , M 6 L 4 and M 4 L 4 can be assembled from them and different metal species.…”

Highly selective visual detection of Fe3+ at ppm level

“…However, the reaction schemes for the synthesis of such reported sensors are very complex, require extreme reaction conditions and are also expensive. On the other hand phenol-based Schiff bases are known as good -conjugated ligands for metal ions [42][43][44][45][46][47][48]. This work is ongoing part of our research interest [49][50][51][52].…”

A Metal–Organic Tetrahedron as a Redox Vehicle to Encapsulate Organic Dyes for Photocatalytic Proton Reduction

“…16 The intrinsic difficulties of mimicking natural systems thus include the feasibility of the processes occurring in aqueous solution and the presence of a well-defined pocket to force the proton reduction center and photosensitizer into close proximity. 17,18 Most importantly, to construct highly efficient and easily operated systems for photocatalytic hydrogen evolution from water, the supramolecular vessels should be designed such that at least one of the two essential components exhibit redox activity and/or light-harvesting ability. 19,20 The supramolecular assembly of predesigned inorganic and organic building blocks is an excellent tool for constructing well-defined, nanosized molecular vessels that catalyze special chemical transformations.…”