电化学传感器论文：电化学传感器 甲基对硫磷 介孔二氧化硅 L-赖氨酸 5-氨基-2-巯基-1,3,4-噻二唑

1、【关键词】电化学传感器 甲基对硫磷 介孔二氧化硅 L-赖氨酸 5-氨基-2-巯基-1,3,4-噻二唑【英文关键词】electroanalysis Methyl-parathion Mesoporous silica oxide L-lysine 5-amino-2-mercapto-1,3,4-thiadiazde电化学传感器论文：甲基对硫磷电化学传感器的研究【中文摘要】化学修饰电极是目前电分析化学中最活跃的一个研究领域。其特色在于能在基体电极表面进行分子设计，使电极达到预定功能，从而有望成为集富集、分离和选择性于一体的新型检测体系，这种方法在电化学和电分析化学显现出诱人的发展前景。基于此，我

2、们构建了几种新型甲基对硫磷电化学传感器，主要研究工作如下：1、本文以十六烷基三甲基溴化铵（CTAB）为模板，在NaOH形成的碱性氛围下合成出了介孔二氧化硅纳米材料。并基于介孔二氧化硅纳米材料制成修饰碳糊电极，以K3为探针，考察了介孔二氧化硅纳米材料修饰碳糊电极的电化学性质，发现其氧化-【英文摘要】Chemically modified electrode is an active research area in electroanalytical chemistry. The attractive characteristic of the modified electrode is tha

3、t its function can be achieved by modified the electrode surface at molecular level.The modification makes the electrode possess many functions such as enrichment, separation and selectivity for the determination. Thus, chemically modified electrode attracted much attention and possesses attractive

4、prospects in analytical chemistry. In this work, we developed several electrochemical sensors for parathion-methyl. The main contents of this work were proposed as following:1. Mesoporous silica (Meso-SiO2) was synthesized using cetyltrimethylammonium bromide (CTAB) as the template under alkaline at

5、mosphere. After that, a mesoporous SiO2-modified carbon paste electrode was fabricated, the electrochemical properties of the modified electrode were characterized using K3Fe(CN)6 as electrochemical probes. Compared to the unmodified electrode, it was found that the redox peak current of K3Fe(CN)6 w

6、as significantly enhanced at the modified electrode. Electrochemical behaviors of methyl-parathion at the modified electrodes were investigated by cyclic voltammetry and square wave voltammetry. The results indicate that the modified electrode can improve the current response of methyl parathion. Th

7、e effects of the electrolyte, preconcentration time, accumulation potential, pH value, mesoporous silica dosage, scanning rate and other conditions on the oxidation peak current was investigated. Under the optimal conditions, a good linear relationship between the current response and methyl-parathi

8、on concentration was obtained from1.0×10-5mol·L-1to1.0×10-7mol·L-1with the equation of Ip (A)=1.885c(mol·L-1)+0.1247(R=0.991) and a detection limit of6.0×10-8mol·L-1(S/N=3).2. A novel electrochemical sensor was fabricated with electrochemical polymerization of L-ly

9、sine onto the glassy carbon electrode (GCE) surface. The electrochemical properties of poly-L-lysine modified electrode was investigated using K3Fe(CN)6 as probes. The results indicates that the redox peak current at the L-lysine modified glassy carbon electrode was significantly enhanced. Electroch

10、emical behaviors of methyl-parathion on the modified electrodes were investigated thoroughly. The results indicated that poly-L-lysine film modified glass carbon electrodes can improve the current response of methyl-parathion. The effects of electrolyte, accumulation time, accumulation potential, pH

11、 value and scan rate were optimized. Under the optimal conditions, the oxidation peak current of methyl-parathion is linearly releated to its concentration in the range from1.0×10-6mol·L-1to1.0×10-4mol·L-1, the linear equation is Ip(A)=0.4796c(mol·L-1)+39.313(R=0.993) and th

12、e detection limit is4.0×10-7mol·L-1(S/N=3). Finally, the modified film electrode was successfully applied to determine methyl parathion in real samples.3. A poly-2-Mercapto-5-methyl-1,3,4-thiadiazde film modified glassy carbon electrode (p-AMT/GCE) was fabricated by using cyclic voltammetr

13、ic scanning in the potential range from-0.2V to+1.7V. Electrochemical behaviors of methyl-parathion at the modified electrodes were investigated with cyclic voltammetry and square wave voltammetry, the results indicate that the modified electrode shows catalytic effect on the electrochemical reactio

14、n of methyl parathion. Compared to the unmodified glassy carbon electrode, the oxidation peak potential of methyl-parathion shifted negatively about40mV and the oxidation peak current significantly increased. Under the optimal conditions, the oxidation peak current is proportional to methyl-parathio

15、n concentration in the range from7.0×10-8mol·L-1tol.0×10-5mol·L-1with a equation of Ip (A)=3.918c(mol·L-1)+4.4550(R=0.994) and a detection limit of4.8×10-8mol·L-1.【目录】甲基对硫磷电化学传感器的研究摘要3-5Abstract5-6第一章 前言11-231 甲基对硫磷的理化性质、农业应用及危害111.1 甲基对硫磷的结构及其理化性质111.2 甲基对硫磷在生物体内的

16、毒理学原理及其对环境的危害112 甲基对硫磷分离分析检测方法的研究现状11-162.1 色谱法12-142.2 免疫测定法142.3 电分析化学法14-163 化学修饰电极的定义、发展历史及其研究现状16-173.1 化学修饰电极的定义163.2 化学修饰电极的历史16-173.3 化学修饰电极的研究现状174 化学修饰电极的分类、修饰方法17-214.1 化学修饰电极的分类17-184.2 化学修饰电极的修饰方法及特征18-204.3 化学修饰的基体电极20-215 课题研究创新点及其研究内容21-226 本论文的研究目的与意义22-23第二章 甲基对硫磷在介孔二氧化硅修饰碳糊电极上的电化学

17、行为研究23-311 引言232 实验部分23-252.1 主要试剂和仪器23-242.2 介孔SiO_2材料的合成242.3 介孔SiO_2修饰碳糊电极的制备242.4 测试方法24-253 结果与讨论25-303.1 介孔二氧化硅修饰碳糊电极的电化学传感特性253.2 介孔二氧化硅的表面形貌表征25-263.3 最佳支持电解质溶液的筛选263.4 富集时间和富集电位对峰电流的影响26-283.5 介孔二氧化硅用量对氧化峰峰电流的影响283.6 扫描速率的影响28-293.7 重现性、线性范围及其检出限293.8 干扰测定29-304 结论30-31第三章 甲基对硫磷在聚L赖氨酸纳米膜修饰玻

18、碳电极上的电化学行为研究31-401 引言312 实验部分31-322.1 主要试剂和仪器31-322.2 聚L赖氨酸修饰玻碳电极的制备322.3 实验方法322.4 分析程序323 结果与讨论32-393.1 聚L赖氨酸膜的结构表征32-333.2 电化学聚合条件的选择333.3 聚L赖氨酸膜的电化学性能研究33-353.4 最佳支持电解质溶液的选择353.5 pH值对甲基对硫磷氧化峰峰电流的影响35-363.6 富集时间对甲基对硫磷氧化峰电流的响应情况36-373.7 线性范围及其最低检出限37-383.8 干扰离子、重现性及稳定性测试383.9 实际样品的测定38-394 结论39-40第四章 聚5氨基2巯基1,3,4噻二唑纳米膜修饰电极的电聚合制备及在甲基对