Fluorescence electrochemical studies

Poliak KW, Leon JW, Frechet JMJ, Maskus M, Abruria HD (1998) Effects of dendrimer generation on site isolation of core moieties electrochemical and fluorescence quenching studies with metalloporphyrin core dendrimers. Chem Matia-10 30... 

Kim, J., A. Izadyar, M. Shen, R. Ishimatsu, and S. Amemiya, Ion permeability and ion-induced permeabihzation of the nuclear pore complex Scanning electrochemical and fluorescence microsocpy studies. Ana/. Chem., Vol. 86, 2014 pp. 2090-2098. 

Emission spectra have been recorded for four aryl-substituted isoindoles rmder conditions of electrochemical stimulation. Electrochemiluminescence, which was easily visible in daylight, was measured at a concentration of 2-10 mM of emitter in V jV-dimethylformamide with platinum electrodes. Emission spectra due to electrochemi-luminescence and to fluorescence were found to be identical, and quantum yields for fluorescence were obtained by irradiation with a calibrated Hght source. Values are given in Table X. As with peak potentials determined by cyclic voltammetry, the results of luminescence studies are interpreted in terms of radical ion intermediates. ... 

Currently, a large spectrum of microbial biosensors have been developed that enable the monitoring of pollutants by measuring light, fluorescence, colour or electric current and electrochemical signal [60]. A recent study [19] shows that whole-cell biosensors based on the detection of changes in gene... 

Frechet and co-workers [32] studied the ability of the dendrimer shell to provide site isolation of the core porphyrin moiety, using benzene-terminated dendrimers Zn[G-n]4P (i.e. 6). From the cyclic voltammograms in CH2C12, the interfacial electron transfer rate between the porphyrin core and the electrode surface decreased with increasing dendrimer generation. However, small molecules like benzyl viologen could still penetrate the shell of 6 to access the porphyrin core as observed from the quenching of porphyrin fluorescence. Their results also revealed that the dendritic shell did not interfere electrochemically or photochemically with the porphyrin core moiety. 

Nearly all the nonfluorescent emission bands reported in these studies have been found at longer wavelengths than the expected fluorescence. They have been variously ascribed to eximers6,15 or to phosphorescence1315 of the electroactive substance. Some apparently do not arise from the electroactive compound itself.16 On oxidation of the pyrene anion radical with Wurster s blue perchlorate, an emission band was obtained which corresponded closely to the known pyrene eximer emission.15 Several spectra obtained from polycyclic aromatic hydrocarbons by electrochemical treatment at constant applied voltage have... 

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