Studies On Fluorescent Chemosensors Of Ions Based On Quinoline And Naphthalimide

Fluorescent chemosensors have attracted the extensive research of chemical workers, due to simple synthesis, high selectivity and sensitivity towards metal ions and aninons. Quinoline and naphthalimide are fluorophores which possess good coordination property and photophysical property. Fluorescent chemosensors based on quinoline and naphthalimides may possess good properties. Silica coated magnetic nanoparticles with magnetic and good biocompatibility, which applied to fluorescent chemosensors can improve the application value. We have designed and synthesized a series of fluorescent chemosensors based on quinoline and naphthalimide, and studied the fluorescent response towards metal ions and aninons. In addition, we synthesized a fluorescent chemosensor loaded on silica coated magnetic nanoparticles. The main content can be described as followed:In chapter 1, the design principle and mechanism of fluorescent chemosensors, have been expounded. Fluorescent chemosensors based on quinolone, naphthalimide and functionalized nanoparticles have also been discussed.In chapter 2, a series of fluorescent chemosensors for Hg2+ based on 8-hydroxyquinoline derivatives have been designed and synthesized. The two of them display highly sensitive and selective response to Hg2+with remarkably fluorescence intensity enhanced in aqueous solution containing 0.2% organic cosolvent. Moreover, the two resumable chemosensors can remove Hg2+ from water by forming mercury-containing compounds, which could be restored to chemosensors by the addition of NaBHH4. Furthermore, the two sensors possess good two-photon fluorescent property, and have been successfully applied for Hg2+ detection in drinking water by both one-and two-photon excited fluorescence with low detection limits (< 2 ppb).In chapter 3, a Schiff base fluorescent chemosensor based on 8-hydroxyquinoline for Zn2+has been designed and synthesized. The sensor displays a highly sensitive and selective response to Zn2+ in HEPES buffer solution with enhanced fluorescence. The chemosensor can distinguish Zn2+ from Cd2+, and the selective response to Zn2+ are unaffected by other metal ions and anions, in addition to the quenching effect ions. Moreover, the sensor has been successfully applied for Zn2+detection in water sample with low detection limit (3.12 ppb).In chapter 4, a colorimetric and ratiometric fluorescent chemosensor based on 1, 8-naphthalimide for Hg2+ has been developed based on mercury ion-promoted hydrolysis of aryl vinyl ether. The chemosensor displays a highly sensitive and selective response with significant changes in both color (from colorless to jade-yellow) and fluorescence (from blue to green) in aqueous solution. The chemosensor exhibits ratiometric fluorescent response towards Hg2+ with a very low detection limit (0.72 ppb), which can be used to detect Hg2+ ions in drinking water. Furthermore, the chemosensor has been successfully applied to image of Hg2+ ions in living cells with emission change from blue to green.In chapter 5, functionalized magnetic nanoparticles based on 1,8-naphthalimide as fluorescent chemosensor for Cu2+ and S2- have been designed and synthesized. The sensor can selectively respond to Cu2+ and efficiently separate Cu2+; the consequent product of the sensor and Cu2+ is an excellent indicator for S2-, and can quantitatively detect S2". Furthermore, two-photon confocal fluorescence imaging has showed that the chemosensor could be applied in living cells for monitoring Cu2+ and S2-,...