蛋白质饲料中三聚氰胺的可视化检测
发布时间：2018-09-11 06:24
【摘要】：甲烷氧化菌是甲基菌中的一个分支,它是一种革兰氏阴性菌,直接以甲烷为能源和碳源。甲烷氧化菌素(Methanobactin,Mb)是甲烷氧化菌向周围释放出的一种荧光肽,它由两个丝氨酸、甘氨酸、色氨酸、两个半胱氨酸、蛋氨酸组成,含有与铜高度络合2个氧唑N和2个硫酰S。甲烷氧化菌素能结合和催化还原Au(Ⅲ)为Au(0)。在有对苯二酚的参与下,能够为甲烷氧化菌素还原Au(Ⅲ)提供电子供体,可以持续生成金纳米颗粒,由于金纳米颗粒具有等离子体共振效应,在用紫外可见吸收光谱扫描在500nm到600nm范围内有明显的特征吸收峰,呈现出特殊的颜色,可以用肉眼所识别的颜色变化可以完成某些物质的检测。 近几年来蛋白质饲料中添加三聚氰胺的范围几乎涵盖了整个饲料行业,牛羊饲料、禽饲料、猪饲料和水产饲料、宠物饲料都或多或少地混有“三聚氰胺”,三聚氰胺的加入明显增加了食物中的含氮量,因此迫切需要建立一种简便、有效分析蛋白质饲料和其他食品中的三聚氰胺的快速检测方法。 本论文利用甲烷氧化菌素介导纳米金合成过程可视化的检测蛋白质饲料中的三聚氰胺,方便、快捷,检测极限远远低于国家规定的三聚氰胺的1ppm标准。对蛋白质饲料中不同浓度的三聚氰胺进行了检测,考察了蛋白质饲料中几种成分对检测的干扰,计算了该方法的检测限及三聚氰胺的加标回收率。 1、甲烷氧化菌素可以以对苯二酚作为外源电子供体催化Au(Ⅲ)持续还原形成纳米金。研究了金纳米粒子的最佳合成条件,PH=5.1,甲烷氧化菌素Au(Ⅲ)的摩尔比在0.8：1,对苯二酚:Au(Ⅲ)的摩尔比在0.4：1,纳米金随着反应的继续会越来越多,待到反应结束,并对制备的纳米金溶液进行了紫外可见吸收光谱、透射电镜(TEM)分析。 2、研究了甲烷氧化菌素介导纳米金合成过程中检测三聚氰胺的机理,由于甲烷氧化菌素可以还原Au(Ⅲ)形成纳米金,溶液呈现酒红色或葡紫色,而三聚氰胺可以抑制甲烷氧化菌素还原Au(Ⅲ)形成纳米金,所以溶液没有颜色变化,通过比色法可以很直观的检测三聚氰胺,通过紫外可见吸收光谱对加入三聚氰胺和未加入三聚氰胺的样品在200nm到800nm范围内进行扫描,可以发现未加入三聚氰胺的在500nm到600nm内有明显的特征吸收峰,证明有金纳米颗粒的形成,加入三聚氰胺的则在此范围内没有吸收峰,说明没有金纳米颗粒的生成。检测三聚氰胺的最佳条件,室温下,PH=5.1,甲烷氧化菌素Au(Ⅲ)在0.7：1,对苯二酚Au(Ⅲ)在0.25：1的条件下,对不同浓度的三聚氰胺进行检测了实验,检测最低限达到了0.6ppm,远远低于国家标准的1ppm. 3、检测蛋白质饲料中的三聚氰胺原理是依据是三聚氰胺能阻止甲烷氧化菌素催化还原Au(Ⅲ)生成纳米金,通过比色法来检测三聚氰胺。实验表明,三聚氰胺的浓度与此浓度下形成的金纳米颗粒有着良好的线性关系,用紫外可见吸收光谱可以实现定量的检测,检测范围在0.05ppm到0.5ppm。用肉眼检测限度为0.6ppm,加标回收率在97-103%。通过紫外可见吸收光谱对可能存在的干扰因素检测发现只有Vb12及V。有非常小的影响。
[Abstract]:Methanobactin (Mb) is a fluorescent peptide released from methane-oxidizing bacteria. It consists of two serine, glycine, tryptophan, two cysteines, and methionine, which are high in copper. Complexing 2 Oxazoles N with 2 thionyl S. methane oxidizing bacteriocins can bind and catalyze the reduction of Au (III) to Au (0). With the participation of hydroquinone, it can provide electron donors for the reduction of Au (III) by methane oxidizing bacteriocins, and can continuously form gold nanoparticles. Because of the plasma resonance effect of gold nanoparticles, ultraviolet-visible absorption spectroscopy is used to scan the gold nanoparticles. The trace has obvious characteristic absorption peaks in the range of 500 nm to 600 nm, showing a special color, which can be used to detect certain substances by the color change recognized by the naked eye.
In recent years, the range of melamine added to protein feed has covered almost all the feed industry, * cattle and sheep feed, poultry feed, pig feed and aquatic feed, and pet feed mixed with melamine more or less. The addition of melamine significantly increased the nitrogen content in food. Therefore, it is urgent to establish a simple and effective method. A rapid method for the determination of melamine in protein feed and other foods.
Melamine in protein feed was detected visually by methane oxidizing bacteriocin-mediated synthesis of gold nanoparticles in this paper. It was convenient, rapid and the detection limit was far lower than the 1 ppm standard of melamine stipulated by the state. The detection limit and the recovery rate of melamine were calculated.
1. Hydroquinone can be used as an external electron donor to catalyze the continuous reduction of Au (III) to form gold nanoparticles. The optimum conditions for the synthesis of gold nanoparticles were studied. The molar ratio of Au (III) to methane oxidizing bacteriocin was 0.8:1, and the molar ratio of hydroquinone to Au (III) was 0.4:1. At the end of the reaction, ultraviolet-visible absorption spectra and transmission electron microscopy (TEM) were used to analyze the gold nanoparticles.
2. The mechanism of detecting melamine in the process of synthesizing Gold Nanoparticles Mediated by methane oxidizing bacteriocin was studied. Because methane oxidizing bacteriocin can reduce Au (III) to form gold nanoparticles, the solution appears wine red or purple, while melamine can inhibit the reduction of Au (III) to form gold nanoparticles by methane oxidizing bacteriocin, so the solution has no color change through colorimetry. The method can be used to detect melamine directly. The samples with and without melamine were scanned in the range of 200 nm to 800 nm by UV-Vis absorption spectroscopy. It was found that there were obvious characteristic absorption peaks in the range of 500 nm to 600 nm without melamine. It was proved that gold nanoparticles were formed and melamine was added. At room temperature, PH = 5.1, methane oxidizing bacteriocin Au (III) at 0.7:1, hydroquinone Au (III) at 0.25:1, the detection limit of different concentrations of melamine reached 0.6 ppm, far below. National standard 1ppm.
3. The principle of detecting melamine in protein feed is based on the fact that melamine can prevent the catalytic reduction of Au (III) by methane oxidizing bacteriocin to form gold nanoparticles. Melamine is detected by colorimetric method. The experimental results show that the concentration of melamine has a good linear relationship with the gold nanoparticles formed at this concentration. The UV-Vis absorption spectrum is used. Quantitative detection can be achieved with a detection range of 0.05 ppm to 0.5 ppm. The detection limit is 0.6 ppm with the naked eye, and the recovery rate is 97-103%. Only Vb12 and V. have very small influence on the possible interference factors detected by UV-Vis absorption spectroscopy.
【学位授予单位】：哈尔滨商业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：O657.32;S816.4
本文编号：2235872
[Abstract]:Methanobactin (Mb) is a fluorescent peptide released from methane-oxidizing bacteria. It consists of two serine, glycine, tryptophan, two cysteines, and methionine, which are high in copper. Complexing 2 Oxazoles N with 2 thionyl S. methane oxidizing bacteriocins can bind and catalyze the reduction of Au (III) to Au (0). With the participation of hydroquinone, it can provide electron donors for the reduction of Au (III) by methane oxidizing bacteriocins, and can continuously form gold nanoparticles. Because of the plasma resonance effect of gold nanoparticles, ultraviolet-visible absorption spectroscopy is used to scan the gold nanoparticles. The trace has obvious characteristic absorption peaks in the range of 500 nm to 600 nm, showing a special color, which can be used to detect certain substances by the color change recognized by the naked eye.
In recent years, the range of melamine added to protein feed has covered almost all the feed industry, * cattle and sheep feed, poultry feed, pig feed and aquatic feed, and pet feed mixed with melamine more or less. The addition of melamine significantly increased the nitrogen content in food. Therefore, it is urgent to establish a simple and effective method. A rapid method for the determination of melamine in protein feed and other foods.
Melamine in protein feed was detected visually by methane oxidizing bacteriocin-mediated synthesis of gold nanoparticles in this paper. It was convenient, rapid and the detection limit was far lower than the 1 ppm standard of melamine stipulated by the state. The detection limit and the recovery rate of melamine were calculated.
1. Hydroquinone can be used as an external electron donor to catalyze the continuous reduction of Au (III) to form gold nanoparticles. The optimum conditions for the synthesis of gold nanoparticles were studied. The molar ratio of Au (III) to methane oxidizing bacteriocin was 0.8:1, and the molar ratio of hydroquinone to Au (III) was 0.4:1. At the end of the reaction, ultraviolet-visible absorption spectra and transmission electron microscopy (TEM) were used to analyze the gold nanoparticles.
2. The mechanism of detecting melamine in the process of synthesizing Gold Nanoparticles Mediated by methane oxidizing bacteriocin was studied. Because methane oxidizing bacteriocin can reduce Au (III) to form gold nanoparticles, the solution appears wine red or purple, while melamine can inhibit the reduction of Au (III) to form gold nanoparticles by methane oxidizing bacteriocin, so the solution has no color change through colorimetry. The method can be used to detect melamine directly. The samples with and without melamine were scanned in the range of 200 nm to 800 nm by UV-Vis absorption spectroscopy. It was found that there were obvious characteristic absorption peaks in the range of 500 nm to 600 nm without melamine. It was proved that gold nanoparticles were formed and melamine was added. At room temperature, PH = 5.1, methane oxidizing bacteriocin Au (III) at 0.7:1, hydroquinone Au (III) at 0.25:1, the detection limit of different concentrations of melamine reached 0.6 ppm, far below. National standard 1ppm.
3. The principle of detecting melamine in protein feed is based on the fact that melamine can prevent the catalytic reduction of Au (III) by methane oxidizing bacteriocin to form gold nanoparticles. Melamine is detected by colorimetric method. The experimental results show that the concentration of melamine has a good linear relationship with the gold nanoparticles formed at this concentration. The UV-Vis absorption spectrum is used. Quantitative detection can be achieved with a detection range of 0.05 ppm to 0.5 ppm. The detection limit is 0.6 ppm with the naked eye, and the recovery rate is 97-103%. Only Vb12 and V. have very small influence on the possible interference factors detected by UV-Vis absorption spectroscopy.
【学位授予单位】：哈尔滨商业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：O657.32;S816.4
【参考文献】
相关期刊论文 前4条
1 田强兵;;分析化学中检出限和测定下限的探讨[J];化学分析计量;2007年03期
2 吕涛;冯奇;史利涛;王新;;分析方法检出限的确定[J];漯河职业技术学院学报;2007年04期
3 黄春丽;黄和;刘文侠;高平;黄国方;李志清;陈宏;罗林;;三聚氰胺的毒性残留及检测方法研究进展[J];南方水产科学;2011年03期
4 石利利;单正军;蔡道基;;三唑磷农药在土壤中的降解与吸附特性研究[J];农业环境科学学报;2006年03期
相关博士学位论文 前1条
1 刘雪平;基于纳米金信号转换和信号放大的新型生物传感技术研究[D];湖南大学;2009年
，本文编号：2235872
本文链接：https://www.wllwen.com/yixuelunwen/dongwuyixue/2235872.html
