| Environmental Estrogens?EEs?are a kind of substances with estrogen-like activity in the body,and they are stable,not easy to be destroyed,and have a long half-life.It can disrupt endocrine activity in the body and threaten human health.In addition,it is easy for EEs to enrich in an ecological environment.Therefore,the development and improvement of EEs detection technology is of great significance for ensuring environmental and drinking water safety,protecting human health and maintaining ecological balance.The analysis methods of EEs based on chromatographic mass spectrometry and immunoassay are accurate and reliable,but they rely on expensive instruments,professional operations,etc.Hence,it is necessary to establish and improve a new detection technique for rapid and sensitive analysis of EEs.In this paper,from the perspective of developing a new sensing platform for detecting EEs,novel sensing platforms were established to detect 17?-estradiol?17?-E2?and bisphenol A?BPA?by electrochemiluminescence?ECL?technique and based on tripyridyl ruthenium(Ru?bpy?32+)and carbon quantum dots?CDs?.And the degradation of BPA in water environment was further investigated.The work of this thesis mainly includes the following three parts:?1?Based on the carboxylated terpyridine pyridinium(Ru?dcbpy?32+)and nitrogen-doped carbon quantum dots?NCDs?system,using the quenching effect of17?-E2 on the system,a simple and rapid ECL sensor was prepared for the detection of 17?-E2 in water sample.Using the mechanism of NCDs as co-reactant of Ru?dcbpy?32+to enhance Ru?dcbpy?32+ECL signal effectively,the effect of experimental conditions on the analysis performance of 17?-E2 was systematically investigated.Under the optimal experimental conditions,the linear response range of the sensor for 17?-E2 is from 1.0×10-9 mol L-1 to 2.0×10-6 mol L-1,and the detection limit is 5.0×10-11 mol L-1.The sensor has been successfully applied to the detection of17?-E2 in water samples,and the recovery rate is between 95.5%and 104%.?2?On the basis of the above work,the aptamer was introduced to improve the selectivity of the sensor.Combining with the advantage of aptamer and the system of tripyridyl ruthenium nanoparticles?RuNSs?and poly?ethyleneimine?functionalized nitrogen-doped carbon quantum dots?NCDs@PEI?,a sensitive and selective ECL aptasensor for the determination of BPA in water was constructed.The sensor exhibitsan excellent ECL performance,and the ECLsignal of RuNSs-NCDs@PEI-rGO is 84-time higher than that of the individual RuNSs.The introduction of the aptamer greatly improves the anti-interference ability of the ECL aptansensor.The linear response range of the aptasensor for BPA is from 1.0×10-10 to1.0×10-4 mol L-1,and the detection limit is 3.3×10-11 mol L-1.When the ECL aptamer sensor is used for BPA analysis in water samples,the results obtained are basically consistent with those obtained by high performance liquid chromatography-ultraviolet spectroscopy?HPLC-UV?method,which verifies its good accuracy.?3?Basd on the constructed RuNSs-NCDs@PEI electrochemiluminescent aptamer sensor,the degradation of BPA in tap water and Yangtze River water was systematically studied using five kinds of water treatment methods such as ultrasound,boiling,activated carbon adsorption,ultraviolet disinfection and chlorination degradation.By comparing the degradation laws of different water quality under the same water treatment method,it can be found that the degradation rate of BPA in the Yangtze River water is higher than that in tap water,which is attributed to the fact that microorganisms in the water environment will affect the degradation rate of BPA.It can be found that the BPA degradation rate is basically consistent in both tap water and Yangtze River water by comparing the degradation rules of the same water quality under different water treatment methods.The degradation process of BPA in water shows that when the concentration of BPA is less than 1.0×10-6 mol L-1,the concentration of BPA can be degraded below the national limit?GB 5749-2006?after chlorination and activated carbon adsorption. |
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