Design Of Fluorescent Sensors Based On Quinoline For Phthalates And Mercury Ion

With the rapid development of society, food safety and environmental pollution are increasingly concerned in addition to economic interests. Some substances cannot be biodegraded, even in the case of trace will cause great harm to human health. The traditional detection methods require strict experimental conditions, and the accuracy is susceptible to interference from other similar substances. Therefore, establishment of sensitive, accurate, and rapid detection methods for the determination of these harmful substances is of great significance. This paper developed two new fluorescent sensor for plasticizers in wine and mercury ion in water, respectively. The detailed contents are described as follows:In Chapter One, the progresses in chemical sensor, the type of fluorescent sensor, the sensing mechanism and practical application of fluorescent sensor, and the detection methods for phthalates and mercury ion have been reviewed. Based on this, the purpose and significance of this study were raised.In Chapter Two, a novel functional monomer1-allyl-4-(4-hydroxy phenyl)vinyl)-quinolinium bromide (AHPEQB) was firstly designed and synthesized by condensation and alkylation, and its chemical structure was confirmed by NMR and MS. A series of cross-linked polymers for phthalate were prepared via free radical polymerization using AHPEQB as the functional monomer, and Trimethylolpropane Trimethacrylate (TRIM) as the cross-linker. These polymers were characterized using TG, IR, and BET. The sensing properties of these polymers for phthalate were investigated via fluorescence spectrum, and it was found CpAiTis displayed the best performance. The recognition mechanism was discussed by fluorescence spectrum and a comparison study. Based on this, a new method for plasticizing agent was established, which can be used to detect plasticizer in liquor with good efficiency and good sensitivity (limit of detection:1.1×10-5mol/L by fluorescence).In Chapter Three, a novel turn-on fluorescent sensor for Hg2+and1-allyl-8-hydroxy quinolinium bromide (AHQB) was designed and synthesized by terminal N-alklyl reaction. AHQB exhibited highly selective and sensitive recognition properties toward Hg2+over other competing transition cations and some anions in pure water, with a1:1binding stoichiometry and a limit of detection1.0×10-9mol/L by fluorescence. AHQB also displayed good reversibility. The sensing mechanism of the proposed fluorescence sensor was studied by fluorescence titration,1H NMR titration, and comparison1-methyl-8-hydroxy quinolinium iodide and1-allyl-5-hydroxy quinolinium bromide. The fluorescent sensor showed good recovery in determining the concentration of Hg2+in real wastewater samples.In Chapter Four, the main results and conclusions were summarized, and some recommendations for future work were proposed.