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Copper is a micronutrient essential to human health, and plays a vital role in organisms metabolism, growth and immune system development process. However, excessive intake of copper ions make protein denaturation, loss of physiological activity, so as to endanger the health of the organism, studies have shown that the ratio of copper and zinc by the human body, and the occurrence of certain tumors related. And when the copper content in water to lmg / L, can the fish all died. In addition, seaweed and molluscs are particularly sensitive to copper their drinking water safe concentrations below 10 μg / L,. Currently, copper ion pollution comes mainly from metallurgy, electroplating and chemical industries, the humanity of its long-term excessive use, copper has become an important environmental pollutants. Therefore, the development of high sensitivity rapid detection of trace amounts of copper ions is becoming a hot research. The past 20 years, the detection of copper ions emerging, such as atomic absorption and emission spectrometry, atomic fluorescence spectrometry, and electrochemical methods. However, these methods are expensive equipment or complex sample preparation process defects. Unlike these techniques, fluorescence sensor has a simple preparation, high sensitivity, fast response, good selectivity and does not require external power supply and requires less sample, etc., has gradually become a powerful tool in the detection and quantification of heavy metal ions in biological testing and environmental testing in a wide range of application, been hot research scholars. Since the 1990s, nanotechnology rapid development, with high resolution, response time and easy preparation advantages of fluorescent nanoparticle sensors have been applied in many fields of environmental science, biomedical, and food science. In this thesis, the organic / inorganic nanocomposite lipid and phospholipid (DMPE) was prepared from organic / inorganic nanocomposite liposomes, hydrophobic fluorescent dye Nile red (Nile red, NR) is embedded into the compound liposome hydrophobic lipid qualitative bilayer, its surface is covered a layer of only the crosslinked silicone mesh molecular thickness, i.e. Si-O-Si network structure. Studies have shown that this organic / inorganic nano-composite liposomes not only retains the essential characteristics of the traditional liposome lipid bilayer and hydrophilic cavity surface hydrophilic, biocompatible and water-soluble , etc., and stability is also significantly improved, to maintain the integrity of its dimensional vesicle structure of the novel composite liposome on a solid substrate, and is not broken in the case of the presence of a surfactant, thus avoiding the entrapped fluorescent dye leaks . Moreover, the composite liposome uniform particle size, surface significantly electropositive. Novel Composite liposome solution is clear and transparent, having many Si-OH group can be modified due to the particle surface, rich in physical and chemical properties and therefore can use the composite liposomes and a polyelectrolyte of opposite charge as the raw material, the use of layers from assembled Nanostructured ultrathin films. DMPE composite liposomes can be combined with copper ions, copper ions, as the energy acceptor to accept the energy from the energy donor nile red molecule, so that the fluorescence of the Nile red molecules quenching occurs, therefore, according to the fluorescent nanoparticles dispersed The fluid system in the fluorescence quenching phenomenon can be realized the detection of the copper ions in the water. The research shows that the impact DMPE in the composite liposome The percentage of the sensitivity of fluorescent nanoparticles stability and copper ions. Experimental results show that when the complex lipid / DMPE molar ratio of 5:2, the fluorescent nano Preferably, the stability of the particles, and the comparison with the parallel sample of copper ions having the highest sensitivity, undiluted fluorescent nanoparticle dispersion liquid system The detection limit of the copper ions 0.2μM, and when the addition of 100μM of copper ions, the fluorescence quenching efficiency reached 92%. The fluorescent nanoparticles dispersed liquid system for the detection effect of copper ions from the influence of the concentration of salt ions and other coexisting anions and cations, that this new composite liposome good selectivity for copper ions, copper ions fast and high The sensitivity for the detection of an ideal material.
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