【作者】 刘绍从；

【导师】 李淑芬；

【作者基本信息】 天津大学 ， 化学工艺， 2007， 博士

【摘要】 食品安全问题已成为社会各界广泛关注的热点问题。为防止食品污染和有害因素对人体的危害,保障人民身体健康,开展食品,食品添加剂,包装材料和有关环境中有害化学物质残留的检测技术研究具有积极作用和重要意义。本文结合食品安全中亟待解决的重点和难点,对四类有机有害化学物残留量的检测技术进行了研究。首先对糖精钠,柠檬酸、苯甲酸钠等食品添加剂中有害有机挥发杂质—二氯甲烷、三氯甲烷、苯、三氯乙烯和1、4-二噁烷的固相微萃取/气相色谱联用(SPME/GC)检测技术进行了研究。以聚二甲基硅氧烷(PDMS)涂层的萃取纤维萃取糖精钠,柠檬酸、苯甲酸钠溶液中的待测组分,以HP-5毛细管柱为分离柱,火焰离子化检测器(FID)定量测定。优化了固相微萃取条件,进行了方法的检出限、精密度、回收率试验。五种组分的回收率在97.3%～103.9%之间。开展了食用酒精和酿酒发酵产品中微量丁二酮和苯乙烯残留气相色谱/质谱联用(GC/MS)检测技术研究。选用新型的HP-PLOT U毛细管色谱柱,优化了色谱质谱条件,实现了丁二酮和乙醇的基线分离,在25 min内一次完成对食用酒精和酿酒发酵产品中微量丁二酮和苯乙烯含量的分离测定。方法平均加标回收率为94.0%～105.0%。分别建立了气相色谱/质谱联用(GC/MS)技术和液相色谱-质谱/质谱联用(LC-MS/MS)技术测定包装材料中痕量的全氟辛酸(PFOA)及其盐类物质。以快速溶剂萃取(ASE)技术萃取包装材料中的PFOA及其盐类物质,萃取液经过滤、浓缩后进行LC-MS/MS分析,外标法进行定量测定;或与乙酰氯衍生化试剂衍生化反应后进行GC/MS分析,以全氟癸酸(PFDA)为内标物,内标标准曲线法定量。利用建立的方法首次分别测定了14种包装材料,测试结果表明,聚四氟乙烯包装材料中含有约0.13ng/g的PFOA及其盐类物质。本研究建立了超临界流体萃取-固相微萃取/气相色谱/质谱联用(SFE-HS-SPME/GC/MS)测定海带、海蛤及天津海河水中六种不同形态有机锡含量的检测技术。优化了超临界流体萃取和顶空固相微萃取条件,海蛤样品经超临界流体萃取后,用浓度为2.0%的四乙基硼化钠(NaBEt4)进行衍生化处理,用固相微萃取富集后,进行GC/MS分析。方法的精密度、回收率、最低检出限和线性范围满足海带、海蛤和环境水样品中五种痕量有机锡检测的要求。本文还以CH2Cl2、CHCl3、C6H6、C2H4Cl3和C4H8O2五种挥发性有机物质的水溶液作为研究对象,对Jiu Ai提出的非平衡态SPME萃取方程的适用性进行进行了实验与理论研究。结果表明,在SPME吸附平衡达到之前,吸附量和样品在基质中初始浓度具有良好的线性关系;但该线性范围与所选物系的初始浓度范围和萃取时间有明显的关系。更多还原

【Abstract】 Food safety has become a major concern of the society in recent years. In order to make improvement in human health and environment protection, it is quite necessary and of great significance to do the research on determination of harmful residues in foods, food additives, packaging materials and aquatic environment for protection of human health and prevention of food contamination.In this thesis determination of four kinds of hazardous organic substances in foods and related materials were investigated, which are considered as very important parts of food safety project.First, research on determination of volatile impurities such as dichloromethane, chloroform, benzene, trichloroethylene, and 1,4-dioxane in saccharin sodium, benzoate sodium and citric acid food additive using solid phase microextraction technique was studied. The polydimethylsilicane (PDMS) fiber was used to extract the target components. The analytical column was HP-5 and the detector was flame ionized detector (FID). The conditions of SPME were optimized and the recoveries of the five harmful impurities were in the ranges between 97.3%～103.9.Second, trace amounts of 2, 3-butanedione and styrene in the edible alcohol and brewed products were determined by gas chromatography/mass spectrometry (GC/MS) technique. A new type of HP-PLOT U capillary column was used for the separation of 2, 3-butanedione and styrene. The results show that 2,3-butanedione styrene and alcohol can be baseline separated. The recoveries of the method were between 94.0%～105.0%.Third, two test methods using gas chromatograph/mass (GC/MS) or liquid chromatograph-mass/mass (LC-MS/MS) for the determination of perflurooctanoic acid (PFOA) and its salts in packaging materials were established. Accelerated solvent extraction (ASE) technique was used to extract perflurooctanoic acid (PFOA) and its salts from packaging materials. After filtration and concentration, the extract could be directly quantified by liquid chromatography-mass/mass (LC-MS-MS) method. When GC/MS was used, the derivation of the extract with NaBEt4 was needed before the sample was analyzed, and the perflurodecanoic acid(PFDA) was used as an internal standard. The established methods was employed for detecting 14 kinds of packaging materials, in which a kind of polytertfluroethylene (PTFE) film was detected to contain PFOA and its salts, and the content was 0.13ng/g.Finally, a new rapid and green method of off-line supercritical fluid extraction (SFE) /headspace solid-phase microextraction (/HS-SPME) / GC/MS was established for the determination of organotin compounds in clam, kelp samples. The optimization of SFE and HS-SPME conditions was conducted. SFE extract was ethylated with 1% (w/v) sodium tetraethylborate (NaBEt4) in pH 4 buffer solution and simultaneously adsorbed by HS-SPME with polydimethylsiloxane-divinylbenzene (PDMS/DVB) fiber at 50℃for 30 min, and then GC/MS quantification was performed. Precision, limits of detection (LOD), and linear range of the method established can meet quantification of five kinds of organotin compounds in biotic sample.A theoretical model proposed by Jiu Ai for dealing with solid phase microextraction for quantitative analysis in nonequilibrium situations was tested by experimental and theoretical studies in order to verify its suitability, where five hydrous solution of volatile organic substances of CH2Cl2、CHCl3、C6H6、C2H4Cl3 and C4H8O2 were used as tested systems. The results show that a linearly proportional relationship exists between the adsorbed analyte and its initial concentration in the sample matrix before adsorption equilibrium was attained, in which the ranges of the initial concentration and adsorption time have obviously influences on the linear relationship which depends on the tested systems.更多还原