A novel Schiff-base fluorescent probe 6,6’-((1E,1’E)-(ethane-1,2-diylbis(azaneylylidene))bis-(methaneylylidene))bis(3-(diethylamino)phenol)(L) was derived from the 2:1 M condensation of 4-(diethylamino)-2-hydroxybenzaldehyde with ethylenediamine and characterized by 1H NMR,13C NMR and FT-IR spectroscopies.The results of spectral analysis showed that the probe L is selective and sensitive to Cu2+.The detection limit of L is found to be 19 nmol·L-1.There... 相似文献
Fluorescence imaging is a powerful technique for continuous observation of dynamic intracellular processes of living cells. Fluorescent probes bearing a fluorescence switching property associated with a specific recognition or reaction of target biomolecule, that is, stimuli-responsibility, are important for fluorescence imaging. Thus, fluorescent probes continue to be developed to support approaches with different design strategies. When compared with simple intensity-changing fluorescent probes, ratiometric fluorescent probes typically offer the advantage of less sensitivity to errors associated with probe concentration, photobleaching, and environmental effects. For intracellular usage, ratiometric fluorescent probes based on small molecules must be loaded into the cells. Thus, probes having intrinsic fluorescence may obscure a change in intracellular signal if the background fluorescence of the remaining extracellular probes is high. To overcome such disadvantages, it is necessary to minimize the extracellular background fluorescence of fluorescent probes. Here, the design strategy of the latent ratiometric fluorescent probe for wash-free ratiometric imaging using a xanthene dye seminapthorhodafluor (SNARF) as the scaffold of fluorophore is discussed. 相似文献
Reactive oxygen species (ROS),such as superoxide radical (O2-)and hydroxyl radical (OH), are thought to be involved in the action of many toxins and several human diseases. Among the various radicals,the hydroxyl radical is presumed to play a central role due to its strong activity. Several methods have been developed to detect hydroxyl radicals. Among them, one of the most commonly used is ESR method. Because of a high-cost instrument, this method is not suitable for routine analysis. Another method is aromatic hydroxylation. Though this method is highly sensitive, the multiple hydroxylation products make the quantitative detection of hydroxyl radical complex. 相似文献
A new non-ionic water-soluble polyfluorene that contains two benzo-18-crown-6 side chains per repeat unit (PFDC) is synthesized and characterized. Upon addition of Pb2+ ions to a solution of PFDC, the PFDC fluorescence is strongly quenched. The minor interference from other metal ions, especial from Cu2+ and Hg2+ions, clearly shows that the PFDC can be used to detect Pb2+ ions with high selectivity. The fluorescence quenching of PFDC in solution originates from the multivalent coordination of the crown-ether moieties to Pb2+ ions followed by precipitation. In comparison to ionic conjugated polymers, the pH of the medium shows less effect on the binding of non-ionic PFDC to Pb2+ ions.
