| Metal-organic polyhedra and macrocycles represent a unique class of functional molecular containers that display interesting molecular recognition properties and fascinating reactivity reminiscent of the natural enzymes, show promise in catalysis, recognition, separation, stabilizing intermediate and so on. However, the special metal-organic supramolecular structures applied to the identification and catalytic system requires the introduction of the targeted active units, effective cooperation of weak interactions, besides exhibits the intuitive and simple signal output. Based on the above problems, this paper includes three aspects of the design,1) introducing amide groups to improve biological compatibility, construct hydrophilic/hydrophobic environment and work as hydrogen bonding sites,2) choosing excellent fluorescent units as the linkers of metal-organic supramolecular system to build fluorescent MOP with cavities and work as potential aromatic stacking sites, which will make our metal-organic supramolecular system applied in the field of biological, energy and so on.Confined metal-organic tetrahedron Ce-TTS encapsulates molecules of2-phenyl-4,4,5,5-tetra-methylimidazolineyloxyl-3-oxide (PTIO), and NO within the cavity to prompt the spin-trapping reaction and transforms the normal EPR responses into a more sensitive luminescent signaling system with the limit of detection improved to5nM. The experiments proved that our system could be used for monitoring intracellular NO, and compound Ce-TTS is the first example of metal-organic polyhedra successfully used for biological imaging in living cells. Meanwhile, a naphthalimide o-phenylenediamine derivative performed a more sensitive ratiometric signalling response towards NO through efficient FRET process from blue triphenylamine emitter to green naphthalimide emitter. Ce-TTS having size restrictions and integrating multiple weak interactions, such as hydrogen bonding, p-stacking and hydrophilic/lipophilic interactions in a controllable way within it’s cavity, was used to selectively recognize tryptophan over other natural amino acids and Trp-containing peptides, which realized fluorescent imaging in living cells and quantificational detection of Trp in serum samples. The methods for detecting Trp were more simple, convenient and high sensitive. On the other hand,1H NMR and luminescent reaction tracing of the cyanosilylation reactions were investigated within Ce-TTS and triphenylamine emitter endowed the intrinsic character of a smart molecular flask with a size-selectively enzyme-like catalysis behaviors. The enzymatic-like catalysis behavior of the catalysis reactions could be luminescently tracked and extended to catalysis of other oxidation reaction.Two trinuclear Zn-based cyclohelicates Zn-PDB and Zn-PMB were self-assembled for host-guest behaviour towards Glutathione (GSH) and its’component amino acids. Uv-vis absorption titration and NMR titrations of Zn-PDB and Zn-PMB upon addition of the above mentioned guests suggested that the Glu residue of GSH was positioned within the cavity, thereinto the COO-groups interacted with metal ions through static interactions and the Cys moiety of GSH interacted with the amide groups sited in host molecules through hydrogen bonding interactions to produce measurable spectral changes. A photoactive metal-organic cyclohelicate Co-TMB with triphenylamine photosensitizer for light-driven H2production was constructed with a TON value about47. The system exhibited enzymatic behaviour and its activity was inhibited by the encapsulation of ATP. Another system Co-QDB supramolecular complex has been developed for H2generation. The efficiencies of hydrogen production relied on host-guest behaviors between Co-QDB and the dyes, indicating that the supramolecular host-guest interactions play important roles for H2production. And this system exhibited high stability and efficiency for hydrogen production with the TON up to550, with the turnover frequency (TOF) about126h-1. This supramolecular system provided a new platform for H2production. |
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