基于Fenton反应和共振瑞利散射光谱检测食品中的三种添加物

发布时间：2019-06-18 12:12

【摘要】：苯甲酸（Benzoic acid；BA）是常用的食品添加剂，由于对食品具有保鲜防腐作用，非法超标添加BA的现象时有发生。过量食用BA影响人体健康，可能诱发癌症。BA含量的卫生检测是食品安全评价的重要内容之一，加强对BA的卫生检验十分必要。邻苯二甲酸二丁酯（Dibutyl phthalate；DBP）是一种塑料增塑剂（Plasticizer），是一种重要的环境荷尔蒙物质；我国和美国国家环保局（EPA）都将DBP列为环境优先控制有毒污染物。三聚氰胺（Melamine；MM）通常用于生产三聚氰胺/甲醛树脂。在人体内，MM容易形成难溶性盐结晶，导致尿路系统结石、膀胱上皮增生等，严重危害人体健康。DBP和MM都是重要的工业原料，是禁用的食品添加物质。由于增塑剂对一些食品产品具有特殊的功效，加入MM可虚假提高乳制品的蛋白质含量，近年来，DBP和MM都被非法用作食品添加物，引发了食品安全突发事件，引起社会强烈反响。检测食品中的DBP和MM已经成为业内和社会高度关注的食品安全工作，研究建立这三种食品添加物质新的检测方法具有重要卫生学意义。本文基于Fenton反应和共振瑞利散射光谱，研究建立了BA、DBP和MM三种有毒有害物质的荧光光谱、或共振瑞利散射光谱检测新方法，为大面积排查和检测这三种食品添加物质提供了实用的新方法。本文第二章基于Fenton反应建立了苯甲酸的荧光光谱卫生检测新方法。在pH=7.6的近中性环境中，，以EDTA-Fe2+/H2O2为Fenton试剂，用苯甲酸捕获Fenton反应产生的·OH自由基，形成荧光物质羟基苯甲酸。在λex=303nm，λem=414nm，通带宽度10nm条件下，测定待测溶液的发射荧光强度，标准曲线法定量检测食品的苯甲酸。测定7.0×10-5、1.5×10-4和5.0×10-4mol/L三种浓度水平苯甲酸的RSD=0.40%~1.40%；平行测定空白溶液的s=0.035，RSD=3.30%。线性回归方程为F=98.76c－4.12，（c,×10-4mol/L），r=0.9992。检出限DL=1.06×10-7mol/L；测定下限为3.53×10-7mol/L；测定线性范围为3.53×10-7~9.0×10-4mol/L。样品测定回收率P=96.50%~102.50%，RSD=2.66%。新方法的测定线性范围宽，检出限低，应用广泛；样品处理方法简单，操作简便，实际样品测定精密、准确，测定结果令人满意。本文第三章，Fenton反应产生羟基自由基（·OH），DBP水解产生邻苯二甲酸钠，二者反应生成荧光物质羟基邻苯二甲酸钠，据此建立了荧光光谱法间接测定样品中DBP的新方法。在优化的反应条件下，在2.8×10-7~2.3×10-4mol/L浓度范围内，荧光强度与DBP的浓度之间有良好的线性关系，其回归方程为：ΔF=18.47c－11.338（c,10-5mol/L），r=0.9970；方法检出限为8.4×10-8mol/L，相对标准偏差RSD=1.4%~2.6%；样品加标回收率96.73%~105.68%。方法准确、灵敏。本文第四章基于共振瑞利散射光谱的特点，建立了共振瑞利散射光谱测定食品中三聚氰胺的新方法。在pH=5.5的B-R缓冲溶液中，在四氢呋喃介质中，三聚氰胺与巴比妥以非共价键方式结合形成聚集体，激发产生强烈的共振瑞利散射。浓度为3.03×10-8～1.60×10-7mol/L时，体系在λ=296nm处的共振光散射强度（的无私帮助和支持。ΔI）值与三聚氰胺的浓度成线性关系，线性回归方程为ΔI=1.59c+9.70(c,10-9mol/L)，相关系数r＝0.9991，检出限为9.1×10-9mol/L。实验分别对4.0×10-8、8.0×10-8、1.2×10-7mol/L的三聚氰胺标准溶液分别进行11次平行测定，相对标准偏差分别为4.54％、3.31％、4.61％，样品加标回收率为95.0％～97.5％。方法精密度、准确度好，灵敏，操作简便，用于食品中三聚氰胺的测定，结果满意。
[Abstract]:Benzoic acid (BA) is a commonly used food additive. The excessive consumption of the BA affects the health of the human body and may induce cancer. The health detection of BA content is one of the important contents of food safety evaluation, and it is necessary to strengthen the health inspection of BA. Dibutyl phthalate (DBP) is a plastic plasticizer, an important environmental hormone substance, and China and the United States Environmental Protection Agency (EPA) have given DBP a priority for environmental priority control of toxic pollutants. Melamine; MM) is usually used to produce a melamine/ formaldehyde tree In human body, MM is easy to form hard-soluble salt crystallization, leading to urinary tract system calculus, bladder epithelial hyperplasia, and the like, and seriously harm human health. Kang. DBP and MM are important industrial raw materials and are the banned food additives. In recent years, DBP and MM have been illegally used as food additives, and food safety emergencies have been caused by the fact that the plasticizer has special effect on some food products. In recent years, both DBP and MM have been used as food additives. In response, the detection of DBP and MM in the food has become a high-priority food safety work in the industry and society, and the new detection methods for the establishment of these three kinds of food additives are of great significance. In this paper, based on the Fenton reaction and the resonance Rayleigh scattering spectrum, the fluorescence spectra of three kinds of toxic and harmful substances, such as BA, DBP and MM, or the new method for detecting the resonance Rayleigh scattering spectrum, are established. In the second chapter, the fluorescence spectrum of benzoic acid is established based on the Fenton reaction. In the near-neutral environment with pH = 7.6, a Fenton reagent with EDTA-Fe2 +/ H2O2 was used to capture the 路 OH radical produced by Fenton reaction with benzoic acid to form a fluorescent substance. Determination of the emission fluorescence intensity of the solution to be tested, the legal amount of the standard curve and the detection of the food at the condition of bex = 303 nm, hem = 414nm, and the pass band width of 10 nm. The RSD of three concentrations of benzoic acid at the concentrations of 7.0,10-5, 1.5,10-4 and 5.0-10-4 mol/ L was 0.40%-1.40%; s = 0.035, RSD = 3.30%. The linear regression equation is F = 98.76 c-4.12, (c,10-4 mol/ L), r = 0 .9992. Detection limit DL = 1.06-10-7 mol/ L; the lower limit of determination is 3.53-10-7 mol/ L; the linear range is determined to be 3.53-10-7-9.0-10-4 mol/ L. The recovery rate of the sample was 96.50% ~ 102.50%, RSD = 2.66%. The new method has a wide range of linear range, low detection limit and wide application; the sample processing method is simple, the operation is simple and convenient, the actual sample is accurate, accurate, and the junction is determined. The results are satisfactory. In the third chapter, the Fenton reaction produces hydroxyl radical (路 OH), DBP is hydrolyzed to produce sodium phthalate, and the reaction of the two produces the sodium phthalate of the fluorescent substance, and the indirect measurement of the sample by the fluorescence spectrometry is established. Under the optimized reaction conditions, there is a good linear relationship between the fluorescence intensity and the concentration of DBP in the range of 2.8 to 10-7-2.3 and 10-4 mol/ L. The regression equation is as follows: (F = 18.47 c-11.338 (c,10-5 mol/ L), r = 0.9970; the detection limit of the method is 8.4-10-8mol/ L, RSD of relative standard deviation is 1.4-2.6%; and the recovery rate of the sample is 96.73%- 105.68%. The method is accurate and sensitive. In the fourth chapter, the resonance Rayleigh scattering spectrum is established based on the characteristics of the resonance Rayleigh scattering spectrum. In the solution of B-R buffer solution with pH = 5.5, the melamine and barbituric acid form aggregates in a non-covalent manner in the solution of B-R buffer solution with pH = 5.5 to excite the production of melamine. Strong resonance Rayleigh scattering. The resonance light scattering intensity at a concentration of 3.03-10-8-1.60-10-7 mol/ L (Unselfish help and support. The value of "I") is linear with the concentration of melamine. The linear regression equation is" I = 1.59c + 9.70 (c,10-9 mol/ L), the correlation coefficient r = 0.9991, and the detection limit is 9.1%. 10-9 mol/ L of melamine standard solution of 4.0-10-8, 8.0-10-8, 1.2-10-7 mol/ L were tested in parallel, and the relative standard deviation was 4.54%, 3.31% and 4.61%, respectively, and the recovery of the sample was 95%. and the method has the advantages of high precision, good accuracy, sensitive and convenient operation,
【学位授予单位】：南华大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：R155.5

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