RESUMO
The development of chemosensors to detect analytes in biologically relevant solutions is a challenging task. We report the synthesis of a fluorescent receptor that combines vibration-induced emission (VIE) and dynamic covalent chemistry for the detection of glucose in aqueous media. We show that the bis-2-(N-methylaminomethyl)phenylboronic acid-decorated N,N'-diphenyl-dihydrodibenzo[a,c]phenazine (DPAC) receptor 1 can detect glucose and discriminate between closely related monosaccharides including those commonly found in blood. Preliminary studies suggest monosaccharides bind to the DPAC-receptor with a 1:1 stoichiometry to produce pseudomacrocyclic complexes, which in turn leads to distinct optical changes in the fluorescent emission of the receptor for each host. Moreover, the complexation-induced change in emission can be detected visually and quantified in a ratiometric way. Our results highlight the potential of VIE-type receptors for the quantitative determination of saccharides in biological samples.
Assuntos
Corantes Fluorescentes/química , Glucose/análise , Corantes Fluorescentes/síntese química , Estrutura Molecular , Espectrometria de Fluorescência , VibraçãoRESUMO
Most of the halogen bonding receptors for anions described use halogen bonding binding sites solely in the anion recognition process; only a few examples report the study of anion receptors in which the halogen bonding interaction has been used in combination with any other non-covalent interaction. With the aims to extend the knowledge in the behaviour of this kind of mixed receptors, we report here the synthesis and the anion recognition and sensing properties of a new halogen- and hydrogen- bonding receptor which binds anions by the cooperation of both non-covalent interactions. Fluorescence studies showed that the behaviour observed in the anion recognition sensing is similar to the one previously described for the halogen analogue and is quite different to the hydrogen one. On the other hand, the association constants obtained by ¹H-NMR data demonstrate that the mixed halogen- and hydrogen-bonding receptor is more selective for SO42- anion than the halogen or hydrogen analogues.
Assuntos
Halogênios/química , Hidrogênio/química , Imidazóis/química , Receptores Artificiais/química , Ânions/química , Ligação de Hidrogênio , Receptores Artificiais/síntese química , Eletricidade Estática , TermodinâmicaRESUMO
The binuclear title complex, di-µ-iodido-bis(-{2-[(benzylamino-κN)meth-yl]phenyl-κC1}palladium(II)), [Pd2I2(C14H14N)2], was prepared by reaction of [Pd{C6H4(CH2NHCH2Ph)-2}(µ-OAc)]2 with NaI. It crystallizes with one discrete mol-ecule in the asymmetric unit. The mol-ecule presents an iodide-bridged dimeric structure with a cisoid arrangement with respect to the C,N-cyclo-palladated ligands. Both PdII atoms have a slightly distorted square-planar coordination environment. Weak inter-molecular contacts of the type C-Hâ¯Pd seem to have a significant influence on the arrangement of the mol-ecules along the b axis in the crystal.