Study On Detection Of Persistent Organic Pollutants By Electrochemiluminescence And Fluorimetric Method

Persistent Organic Pollutants possess the properties of chronicity, cumulative, semi-volatile and highly toxic. They can move by long distance through different kinds of environmental medium such as air, water, biosome and so on, and there are serious harm on human health and environment. The harm of Persistent Organic Pollutants (POPs) is the reason why the government of every country, administration section, academic circle, industry and agriculture, and the public widely pay close attention to them. And now, POPs have become one of worldwide environmental problem which have much attention.Now the main method of detection of POPs is chromatography and mass spectrometry which need precise instrument, good environment for experiment, bridle-wise people and high cost, these made it not suitable for large sample analysis and field analysis. So development quick screening and biological analysis method is of great significance.Electrochemiluminescence (ECL) and fluorescence method are all good methods for detection which have high sensitivity, and regarded as the methods which have larger potential on detection. ECL has the Features of fluorescence method, electrochemistry and chemiluminescence which have high sensitivity, wide linearity range, simple instrument, fast analysis, and good control. The highlighted merit of fluorescence are high sensitivity and high selectivity, simple and direct, good repeatability, light sample, and simple instrument, so fluorescence is regarded as one of the most sensitive detecting methods.Based on above, we developed three works as below in this article:1. pentachlorophenol (PCP) doesn’t have the property of fluorescence, it is a great challenge to establish fluorescence analysis of pentachlorophenol. Under the illumination of ultraviolet and hydrophobic solution, there are chlorine radical on the process of photolysis of PCP, and then react with anthracene (ANT) that the fluorescence intensity of ANT reduce for the effect of electron-withdrawing of chlorine. Based on that, we develop a kind of method by indirect fluorescence to detect PCP. This method doesn’t have complex fluorescent marker reaction. The linear range is from5.0x10-3to 1.0x10-7M, and the detection limit is8.0x10-8M.2. Under the illumination of ultraviolet and aqueous solution, PCP can also be easy to photolysis, but the pH of the solution would be changed. Here is fluorescein which is sensitive to the change of the pH. So we can analysis PCP by monitor the fluorescence of ANT. The linear range is from5.0×104to5.0×10-9M, and the detection limit is2.0×10-9M.3. We study the electrochemical luminescence using titanium dioxide nanotubes (TiO2NTs) as a working electrode and potassium sulfate as altogether reaction agent. Based on the quencher role of polyaromatic hydrocarbon(PAH) to the ECL of TiO2NTs, we develop a ECL method to detect PAH. The height of the uniform structure of TiO2make the electrochemical luminescence intensity stable and strong. Silver nanoparticles electrodeposition on TiO2NTs further enhance the luminous intensity, and provide security to achieve high sensitivity. The linear range is from1.0×10-9to3.0×10-12M, and the detection limit is1.0×10-12M.