Study On Syntheses,Properties And Applications Of Salamo-like Fluorescent Chemosensor Based On Naphthalene-and Benzene-dicarboxaldehyde

In this thesis,four Salamo-like fluorescence chemosensors based on2,3-dimethoxy-1,4-benzenedialdehyde or 2,3-dihydroxy-1,4-naphthalenedialdehyde as the materials and the phenyl or naphthyl as modified group were synthesized.The structures,properties and identification mechanisms of the four sensors were determined by means of UV-vis absorption spectra,fluorescence spectra,nuclear magnetic resonance spectra,high-resolution mass spectrometryet al.Beyond that,in order to broaden the application of the Salamo-type fluorescent sensors,the application of four sensors in environmental water sample detection and fluorescent bio-imaging was studied.The content was mainly consists of the following four parts:1.The current development of fluorescent chemosensor,colorimetric chemosensor and Salamo-like fluorescent chemosensor was mainly introduced.2.The chemosensor HL based on 2,3-dimethoxy-1,4-benzenedialdehyde and2-[O-（1-ethoxyamide）]oxime-6-methoxyphenol was synthesized through Schiff base reaction,and HL could continuously identify Cu²⁺and CN^-ions in ethanol/water（v/v=1/1）system.According to the coordination mechanism,the detection of Cu²⁺ ions could be achieved in the absorption spectra and the fluorescence spectra,but Al³⁺ ions and Cr³⁺ ions could interfere for the recognition.We considered adding F^-ions or hydrogen peroxide as masking agents to remove the interferences of the two kinds of ions.The complex L-Cu²⁺ formed by HL and Cu²⁺ ions could identify CN^-ions by UV-vis absorption spectra and visual observation.A strong absorption peak appears at 500 nm in the visible region and the color of the solution changed significantly.The RGB analysis method was developed according to the color changes and device-free detection was realized.Beyond that,in terms of applications,five kinds of water samples in life were collected separately,and the CN^-ions concentration was detected after pretreatment.Good recovery rates and relative standard deviations were obtained,which further expanded the application of the Salamo-based fluorescent chemosensor in the environment.3.Thechemosensor H₅L basedon 3,9’,10’-trimethoxy-8’-aldehyde-2-[ethylenedioxybis（nitrosomethyldiyne）]phenol and 2-[O-（1-ethoxyamide）]oxime-1-naphthol was synthesized through two-step reactions.H₅L could continuously identify Cu²⁺ ions and Al³⁺ ions/lysine in ethanol/water（v/v=1/1）system.The sensor could detect Cu²⁺ ions by UV-vis absorption spectra and naked eye observation.The sensor could detect Cu²⁺ ions through UV-vis absorption spectra and naked eye observation.Through the significant change of the color of the solution,the RGB analysis method for detection of Cu²⁺ ions in water samples was developed,which could realize fast and simple real-time monitoring.The complex L-Cu²⁺formed by H₅L and Cu²⁺ions could recognize Al³⁺ions and lysine in the fluorescence spectra under different conditions.According to the coordination mechanism,Al³⁺ions could replace Cu²⁺ ions in L-Cu²⁺,and lysine could coordinated with Cu²⁺ ions from L-Cu²⁺complexes,releasing H₅L,both of which result in enhanced fluorescence.In terms of application,confocal fluorescence bioimaging for Al³⁺ ions and lysine by L-Cu²⁺ complex in HeLa cells was completed,which was the further exploration for expanding the application of Salamo-based fluorescent chemosensors in vivo.4.The chemosensor H₆L formed via 2,3-dimethoxy-1,4-benzenedialdehyde and methoxy mono-condensation compound was synthesized through two-step reactions.H₆L could recognize B₄O₇^2- ions in ethanol/water（v/v=9/1）system.In the presence of other anions,the sensor can show highly selectivity to B₄O₇^2- ions and achieve naked eye detection under UV light.Beyond that,H₆L cells have almost no cytotoxicity and used to exogenous bio-imagine detection in zebrafish for the first time was gain successfully.To the best of our knowledge,this was the first time that bis（Salamo）-based fluorescent chemosensor applied to exogenous detection in zebrafish,which expands the application of the Salamo-type fluorescent sensor in the biology.The copper（Ⅱ） complex L-Cu²⁺fluorescence sensor from H₆L was prepared,which shows specific recognition for Al³⁺ ions.The detection mechanism is coordination and chelation fluorescence enhancement effect.