紫外光诱导银纳米簇的合成及几种离子检测
发布时间：2018-10-22 14:14
【摘要】：贵金属纳米簇由于量子尺寸效应表现出特异的光、电及化学性能从而成为纳米材料热门研究领域之一。由于纳米簇的小尺寸、无毒性以及光稳定性等,使其新型荧光探针在化学检测及生物标记等领域作出了突出贡献。光催化对环境中有机物的降解/转化过程起着重要的作用,紫外光既能进行催化还原反应,又能进行催化氧化反应。在有机物存在下,紫外光照射有机物和银离子混合溶液,有机物产生的超氧阴离子能还原银离子制备银纳米簇。因此,本文用光还原法制备银纳米簇并应用于无机离子和金属离子的检测。在紫外光下有机物变色酸易脱色/降解,研究发现加入微量铜离子时能抑制其脱色/降解,据此建立了紫外光照下利用变色酸检测微量铜离子的方法。主要研究内容如下:(1)本文以羧甲基葡聚糖为稳定剂和还原剂,紫外光照射[Ag(NH3)2]OH溶液合成一种新型水溶性荧光银纳米簇;并对其尺寸和形貌进行了TEM,HRTEM和荧光紫外光谱表征。基于银纳米簇与卤素离子间的特定化学反应能够生成Ag X沉淀导致银纳米簇荧光猝灭,从而成功构建了一种检测卤素离子的荧光传感器。在BR缓冲溶液中,Br-对I-的检测具有较强的干扰作用;在氨水条件下,该检测方法对I-具有很高的选择性,能够在I-和Br-共存溶液中识别I-,并且能检测到的I-浓度范围为1.0×10-10~1.0×10-7 mol/L。在BR缓冲溶液中,当I-和Br-共存时能够检测两种离子的总信号响应,因此通过分别检测BR缓冲溶液和氨水介质下的信号响应,实现混合样品中I-和Br-的同时检测。此外,该传感系统已成功地应用于检测海带样品。(2)基于Mn2+与氨水作用生成Mn(OH)2,Mn(OH)2不稳定易被氧化为成Mn O2(不仅难溶于水而且难溶于碱溶液)。紫外光照射[Ag(NH3)2]OH溶液合成一种新型水溶性强荧光银纳米簇,当银纳米簇中加入适当浓度的Mn2+可以引起荧光的减弱甚至猝灭。据此,本文建立了一种在氨水条件下以荧光银纳米簇为探针,荧光分光光度法检测Mn2+的新方法,该方法操作简单,可靠,灵敏度高,在最佳实验条件下检测Mn2+的最低浓度可达1.0×10-10 mol/L。(3)基于紫外光能够催化脱色/降解偶氮有机染料变色酸,同时偶氮型的有机物是一种很好的螯合试剂;当变色酸中加入Cu2+时,变色酸与Cu2+生成一种稳定的铜离子螯合物(Cu2+-CR)能够抑制变色酸脱色/降解,据此建立了在紫外光照下以变色酸为探针检测微量铜离子的方法。变色酸溶液的颜色和最大特征吸收峰值随着Cu2+浓度的变化而变化,且最大特征吸收峰处吸光度的改变值(?A)与Cu2+浓度在5.0?10?9~1.0?10?6 mol/L的范围内呈现良好的线性关系,并且成功的应用于头发中Cu2+含量的检测。
[Abstract]:Noble metal nanoclusters have become one of the hot research fields because of their special optical, electrical and chemical properties due to their quantum size effects. Due to their small size, nontoxicity and photostability, the novel fluorescent probes have made outstanding contributions in the fields of chemical detection and biomarker. Photocatalysis plays an important role in the degradation / transformation of organic compounds in the environment. Ultraviolet light can not only catalyze the reduction reaction but also the catalytic oxidation reaction. In the presence of organic compounds, the superoxide anion produced by organic compounds can reduce silver ions to silver nanoclusters by UV irradiation of mixed solution of organic compounds and silver ions. Therefore, silver nanoclusters were prepared by photoreduction method and applied to the detection of inorganic ions and metal ions. The decolorization / degradation of organic compounds is easy to be decolorized / degraded under ultraviolet light. It is found that the decolorization / degradation of organic compounds can be inhibited by adding trace copper ions. A method for the detection of trace copper ions by chromotropic acid under ultraviolet light has been established. The main contents are as follows: (1) in this paper, a novel water-soluble fluorescent silver nanocluster was synthesized by UV irradiation with [Ag (NH3) 2] OH solution with carboxymethyl dextran as stabilizer and reductant, and its size and morphology were characterized by TEM,HRTEM and fluorescence UV spectroscopy. Based on the specific chemical reaction between silver nanoclusters and halogen ions, a fluorescence sensor for the detection of halogen ions was successfully constructed, which resulted in the fluorescence quenching of silver nanoclusters due to the formation of Ag X precipitation. In BR buffer solution, Br- has strong interference on I- detection, and in ammonia solution, this method has high selectivity to I-, it can recognize I-in I- and Br- coexisting solution, and the concentration of I- can be detected in the range of 1.0 脳 10-10 ~ (-) 1.0 脳 10 ~ (-7) mol/L.. In BR buffer solution, the total signal response of the two ions can be detected when I- and Br- coexist, so the detection of I- and Br- in mixed samples can be realized by detecting the signal responses in BR buffer solution and ammonia solution respectively. In addition, the sensing system has been successfully applied to the detection of kelp samples. (2) based on the interaction of Mn2 and ammonia, Mn (OH) _ 2 mn (OH) _ 2 instability is easily oxidized to Mn O _ 2 (not only insoluble in water but also insoluble in alkali solution). A new type of water-soluble strongly fluorescent silver nanoclusters was synthesized by ultraviolet irradiation of [Ag (NH3) 2] OH solution. When the appropriate concentration of Mn2 was added to the silver nanoclusters, the fluorescence intensity could be weakened or even quenched. Therefore, a new method for the detection of Mn2 using fluorescent silver nanoclusters as probe in ammonia solution has been developed. The method is simple, reliable and sensitive. Under the optimum experimental conditions, the lowest concentration of Mn2 can reach 1.0 脳 10 ~ (-10) mol/L. (3) based on ultraviolet light, it can catalyze decolorization / degradation of chromotropic acid of azo organic dyes, and azo type organic matter is a good chelating reagent. When Cu2 is added to chromotropic acid, A stable copper ion chelate (Cu2-CR) from chromotropic acid and Cu2 can inhibit decolorization / degradation of chromotropic acid. A method for the detection of trace copper ion with chromotropic acid as probe under ultraviolet light was developed. The color and maximum characteristic absorption peak of chromotropic acid solution changed with the change of Cu2 concentration, and there was a good linear relationship between the change value of absorbance at the maximum characteristic absorption peak and the concentration of Cu2 in the range of 5.0 ~ 10 ~ 10 ~ (9) ~ 1.0 ~ (10) ~ 10 ~ (6) mol/L. And successfully applied to the detection of Cu2 content in hair.
【学位授予单位】：湖南科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：O657.3;TB383.1
本文编号：2287385
[Abstract]:Noble metal nanoclusters have become one of the hot research fields because of their special optical, electrical and chemical properties due to their quantum size effects. Due to their small size, nontoxicity and photostability, the novel fluorescent probes have made outstanding contributions in the fields of chemical detection and biomarker. Photocatalysis plays an important role in the degradation / transformation of organic compounds in the environment. Ultraviolet light can not only catalyze the reduction reaction but also the catalytic oxidation reaction. In the presence of organic compounds, the superoxide anion produced by organic compounds can reduce silver ions to silver nanoclusters by UV irradiation of mixed solution of organic compounds and silver ions. Therefore, silver nanoclusters were prepared by photoreduction method and applied to the detection of inorganic ions and metal ions. The decolorization / degradation of organic compounds is easy to be decolorized / degraded under ultraviolet light. It is found that the decolorization / degradation of organic compounds can be inhibited by adding trace copper ions. A method for the detection of trace copper ions by chromotropic acid under ultraviolet light has been established. The main contents are as follows: (1) in this paper, a novel water-soluble fluorescent silver nanocluster was synthesized by UV irradiation with [Ag (NH3) 2] OH solution with carboxymethyl dextran as stabilizer and reductant, and its size and morphology were characterized by TEM,HRTEM and fluorescence UV spectroscopy. Based on the specific chemical reaction between silver nanoclusters and halogen ions, a fluorescence sensor for the detection of halogen ions was successfully constructed, which resulted in the fluorescence quenching of silver nanoclusters due to the formation of Ag X precipitation. In BR buffer solution, Br- has strong interference on I- detection, and in ammonia solution, this method has high selectivity to I-, it can recognize I-in I- and Br- coexisting solution, and the concentration of I- can be detected in the range of 1.0 脳 10-10 ~ (-) 1.0 脳 10 ~ (-7) mol/L.. In BR buffer solution, the total signal response of the two ions can be detected when I- and Br- coexist, so the detection of I- and Br- in mixed samples can be realized by detecting the signal responses in BR buffer solution and ammonia solution respectively. In addition, the sensing system has been successfully applied to the detection of kelp samples. (2) based on the interaction of Mn2 and ammonia, Mn (OH) _ 2 mn (OH) _ 2 instability is easily oxidized to Mn O _ 2 (not only insoluble in water but also insoluble in alkali solution). A new type of water-soluble strongly fluorescent silver nanoclusters was synthesized by ultraviolet irradiation of [Ag (NH3) 2] OH solution. When the appropriate concentration of Mn2 was added to the silver nanoclusters, the fluorescence intensity could be weakened or even quenched. Therefore, a new method for the detection of Mn2 using fluorescent silver nanoclusters as probe in ammonia solution has been developed. The method is simple, reliable and sensitive. Under the optimum experimental conditions, the lowest concentration of Mn2 can reach 1.0 脳 10 ~ (-10) mol/L. (3) based on ultraviolet light, it can catalyze decolorization / degradation of chromotropic acid of azo organic dyes, and azo type organic matter is a good chelating reagent. When Cu2 is added to chromotropic acid, A stable copper ion chelate (Cu2-CR) from chromotropic acid and Cu2 can inhibit decolorization / degradation of chromotropic acid. A method for the detection of trace copper ion with chromotropic acid as probe under ultraviolet light was developed. The color and maximum characteristic absorption peak of chromotropic acid solution changed with the change of Cu2 concentration, and there was a good linear relationship between the change value of absorbance at the maximum characteristic absorption peak and the concentration of Cu2 in the range of 5.0 ~ 10 ~ 10 ~ (9) ~ 1.0 ~ (10) ~ 10 ~ (6) mol/L. And successfully applied to the detection of Cu2 content in hair.
【学位授予单位】：湖南科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：O657.3;TB383.1
【参考文献】
相关期刊论文 前1条
1 墙蔷;倪红卫;幸伟;谢中;魏勇;;银的抗菌作用机理[J];武汉科技大学学报(自然科学版);2007年02期
，本文编号：2287385
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