RESUMO
Bisphenol A is a fluorophoric platform that is used to develop chemosensors for various species. Herein, we report a bisphenol A based Schiff-base molecule, 4,4'-(propane-2,2-diyl)bis(2-((E)-((2-hydroxy-5-methylphenyl)imino)methyl)phenol) (Me-H4L), as a selective chemosensor for Al3+. Among the several metal ions, it shows a significant increment in its fluorescence intensity (50 fold) at 535 nm in the presence of Al3+ ions. The enhanced fluorescence was attributed to the CHEFF mechanism and inhibition of CîN isomerization. The limit of detection value of Me-H4L for Al3+ was determined to be 9.65 µM. Its quantum yield and lifetime increased considerably in the presence of the cation. Some theoretical calculations were performed to explain the interaction between Al3+ and the probe. Furthermore, Me-H4L was applied in cell imaging studies using animal cells and plant roots.
Assuntos
Alumínio , Compostos Benzidrílicos , Corantes Fluorescentes , Fenóis , Raízes de Plantas , Fenóis/química , Fenóis/análise , Compostos Benzidrílicos/química , Compostos Benzidrílicos/análise , Alumínio/análise , Alumínio/química , Raízes de Plantas/química , Corantes Fluorescentes/química , Animais , Bases de Schiff/química , Humanos , Imagem Óptica/métodos , Espectrometria de Fluorescência/métodos , Limite de DetecçãoRESUMO
A chemosensor with two binding pockets facilitates binding of one metal ion in either of the pockets providing a better chance for the interaction and hence recognition of the cation. We report here a chemosensor, namely 2,2'-(1E)-(5,5'-sulfonylbis(2-hydroxy-5,1-phenylene))bis(azan-1-yl-1-ylidene)bis(methan-1-yl-1-ylidene)dinaphthalen-1-ol (H4L-naph), for selective sensing of Al3+ in DMF- HEPES buffer (1:4, v/v, pH 7.4). It shows almost 100-fold fluorescence enhancement at 532 nm (λex = 482 nm) in the presence of Al3+. Its quantum yield and excited state lifetime enhances significantly with the cations. H4L-naph forms a 1:2 complex with Al3+ with an association constant value of 2.18 × 104 M-2. Fluorescence enhancement may be attributed to CHEFF mechanism and restriction of >CN isomerization. Effect of the presence of naphthyl rings instead phenyl ring of a previously reported probe has resulted shifting of excitation/emission peak towards longer wavelength. The probe has been applied to image Al3+ in L6 cells with no significant cytotoxicity.