【作者】 李永波；

【导师】 章竹君；

【作者基本信息】 陕西师范大学 ， 分析化学， 2013， 博士

【摘要】 色谱(Chromatography)是一种高效的分离技术,目前已被广泛地应用到食品安全、药物分析、环境监测、毒物分析、质量控制、生物化工和医疗卫生等领域。高效液相色谱(High-performance liquid chromatography, HPLC)和气相色谱(Gas chromatography, GC)具有分离效能高、选择性好和分析速度快等优点,是目前应用最广泛的两种色谱技术。电化学发光(Electrochemiluminescence, ECL)是通过电化学的方法激发的一种发光现象,是电化学和化学发光相结合的产物。电化学发光不但保留了化学发光原有检出限低、线性范围宽的特点,而且还表现出一些独特的优点,如反应可控性强、节省试剂、可进行原位检测等。但同时,电化学发光选择性差的缺点限制了它的进一步应用。为了拓宽它的应用范围,将电化学发光和分离技术联用是必要的。HPLC和ECL联用不但可以克服单一使用ECL选择性差的缺点,而且可以提高HPLC的灵敏度,是一种应用前景较好的检测技术。气相色谱-质谱(GC/MS)是一种强大的分析技术,兼具气相色谱的强分离效能和质谱的强定性能力。采用GC/MS对食品等基质复杂的样品进行检测,不但可以实现食品中多种杂质和待测物的高效分离,而且也可以对待侧物进行准确定性。本论文首先概述了高效液相色谱、电化学发光传感器和气相色谱-质谱的研究进展,并对近年来高效液相色谱-电化学发光传感器的应用研究以及气相色谱-质谱在食品安全方面的应用进行了归纳和总结。在研究部分,采用对钉联吡啶固定能力强、固定容量大的Nepem-105D全氟液体离子交换溶液和Nepem-211全氟离子交换电导膜来修饰电极。在此基础上设计一种能够实用于HPLC检测的,结构简单、死体积小的流通式ECL检测池。由于Nepem-105D在全氟乙烯基醚结构类似的骨架结构上有更多的支链；C-F键的键长短,键能高(486千焦耳/摩尔),富电子的氟原子具有强烈电负性,导致在相邻之间的氟原子相互排斥。氟原子和氟原子聚合物的C-C沿锯齿链螺旋状分布。同时,由于氟原子体积大于氢原子,它提供了更好地覆盖的C-C链,形成低表而自由I能氟化物保护层。由于Nepem-105D具有良好的热稳定性,化学稳定性和高交换容量,适合通过离子交换来固定Ru(bpy)32+,用于设计简单的单铂丝流通式HPLC-ECL检测器。Nepem-211全氟离子交换电导膜是用Nepem-105D全氟液体离子交换剂,通过树脂流动和掺杂技术制成的一种既具有强的阳离子交换势和高交换容量、高的抗张强度、高的选择性和各向同性,又有高的电导率(0.1s/cm),薄膜厚度可调,自湿度好,线性膨胀低。已被用于燃料电池、钒电池和电渗析等方面。大容量的Ru(bpy)32+可以牢固地固定在这种电导膜上,再紧密地缠绕在回型铂丝上做成工作电极。由此构建的流通式ECL传感器,抗有机溶剂能力强,具有较长期的稳定性。特别适合作为HPLC的检测器。在优化电化学发光传感器条件的基础上,通过对色谱分离条件的优化,建立一套高效液相色谱电化学发光传感器联用新体系,并将这套新体系应用于食品和生物样品的检测。此外,本研究还利用GC/MS的超强的分离和强定性能力对脂肪含量高的糕点样品的防腐剂以及食用菌、茶叶、蔬菜等植物性食品中的多种农药残留量进行了检测。具体研究工作为：基于Nepem-105D全氟离子交换溶液形成的离子交换膜将钌联吡啶(II)固定于单根铂丝电极表面设计制成了一种微型电化学发光传感器,此传感器仅由两根铂丝和一个毛细玻璃管组成,结构非常简单。在最佳实验条件下,连续6次测定氧氟沙星标准溶液(0.3μg mL-1)的日内差为3.6%,连续3天日间差为6.8%。将此传感器与高效液相色谱联用,建立了一套新型的HPLC-ECL检测系统,此系统中,化学发光试剂是被固定的,而且可以反复使用。不需要外加发光试剂流路,装置非常简单,色谱柱后没有液体流入,不会造成样品稀释和峰扩展。由于发光试剂反复使用,大大降低了试剂成本,也减小了试剂排放造成的环境污染。应用此系统成功测定了牛乳样品中的多种FQs药物残留以及血清样品中的3种镇吐药含量。以Nepem-211离子交换电导膜固定钌联吡啶为基础,设计了一个灵敏的流通式ECL传感器。该传感器抗有机溶剂能力强,稳定性好。将此传感器和HPLC联用同时测定红霉素(8.0ngμL*1)和克拉霉素(4.0ngμL-1)11次得到的化学发光强度的RSD分别为1.40%和1.76%,此联用系统成功测定了蜂蜜和猪肉样品中的红霉素和克拉霉素以及尿样中的3种三环类抗抑郁药物。采用相互饱和的乙腈和正己烷,通过快速漩涡混合萃取或超声萃取,在对糕点中富马酸二甲酯萃取的同时实现了对脂肪杂质的去除,建立了一步三相快速提取糕点中富马酸二甲酯的方法。该方法简单、快速、可靠。本研究首次采用GC-ECD实现了对食品中富马酸二甲酯的测定,并将此方法与GC-FID和CG/MS的方法进行了比较,三种方法均可以实现对糕点中富马酸二甲酯的测定,CG/MS的灵敏度最高,GC-ECD的灵敏度高于GC-FID.建立了采用气质联用仪同时测定有机氯、有机磷、拟除虫菊酯类和氨基甲酸酯类共4类49种农药的方法。蔬菜和干性食品中的农药分别用乙腈和丙酮提取,提取液浓缩后采用固相萃取净化。连续三年对286份蔬菜以及30份食用菌和35份袋泡茶样品的农残进行了监测。监测结果显示：袋泡茶、叶类蔬菜、鲜食用菌的农药检出率高于干食用菌。依据GB2763-2012判定,有2.10%的蔬菜样品农药残留超标。更多还原

【Abstract】 Chromatography is a powerful separation technology. Nowdays, it has been widely used in analytical chemistry field, e.g. food safety, pharmaceutical analysis, environment inspection, toxicological analysis, quality control, biological chemistry, clinical etc. Among numerous chromatography methods, high-performance liquid chromatography (HPLC) and gas chromatography (GC) are the most popular tools due to high separation efficiency, improved selectivity, the fast speed of analysis.Electrochemiluminescence (ECL) is the light-emitting phenomena initiated by electrochemical method. It is the combination of CL and electrochemistry. Whilst retaining the advantages of the very low detection limits and the wide linear dynamic range inherent to conventional CL method, ECL also offers many additional advantages, e.g., controllable chemiluminescence reaction, reduced reagent consumption and in situ ECL generation. However, the poor Selective of this method limits its further application. To widen its application, separation technology should be coupled with ECL. HPLC coupled to ECL detection represents an interface between the selectivity of a powerful separation method and the sensitivity of this detection technique.GC/MS is a powerful analytical tool due to high qualitative ability of MS and efficient separations for analytes. When GC/MS was used in food analysis, interfering substances can be separated from analytes by GC and analytes can be accurate detection by MS. Thus, GC/MS is a proper choice to detect thermally stabile, low-polar and volatile analytes in food matrices. With these distinguished advantages, GC/MS is extensively employed for food safety.In this Paper, Advances in HPLC, ECL sensor and GC/MS research in the past years are reviewed. HPLC-ECL system and the application of GC/MS in food safety are also introduced briefly.Nepem-105D perfluorinated ion exchange solution and Nepem-211perfluorinated ion exchange conductance membrane which not only has high capability and high capacity for immobilization of Ru(bpy)32+, but also has high conductivity were used to modify electrode. On this basis, a simple ECL flow cell with low dead volume and good compatibility for HPLC analysis was developed. Nepem-105D has a branched chain perfluorinated vinyl ether structure on a skeletal structure similar to that of PTFE. Since the C-F bond length is short, the bond energy is high (486kJ/mol) and electron-rich fluorine atoms are strongly electronegative, resulting in mutual repulsion between adjacent fluorine atoms and fluorine atoms along the zigzag polymer C-C chain spiral distribution. Also, because the fluorine atomic volume is bigger than the hydrogen atom, it provides better coverage of the C-C chains, forming a low surface free energy fluoride protection layer. As Nepem-105D has good thermal stability, chemical stability and high exchange capacity, Ru(bpy)32+can be exchanged through the ion-exchange process and electrostatic adsorption. Thus, it can be used to develop a simple single Pt wire HPLC-ECL detector. Nepem-211perfluorinated ion exchange conductance membrane is made by new resin flow technology based on Nepem-105D. Resin flow technology can combine with adulterate technology, so Nepem-211has many outstanding features:it not only has the high tensile strength, high selection, isotropy, high conductance (0.1s/cm), but also the effect of self-humidifying and with low linear expansion. It has been applied in fuel cell, vanadium batteries, electrolyzer, electrodialysis and solid electrolyte membrane of electrochemical sensors. Nepem-211membrane has higher exchange capacity, so more Ru(bpy)32+can be immobilized. Immobilized Ru(bpy)32+cannot migrate into the electro-inactive hydrophobic region with time, and it is not destroyed upon exposure to mobile phase containing high organic content. So the flow sensor has high sensitivity and a long life. It is very suitable for HPLC analysis. Based on the optimal conditions of ECL detector and chromatographic separation, a new HPLC-ECL system was established. This system was used to detect trace pharmaceuticals in food and biological samples (eg. blood, urine). In addition, GC/MS was used to detect dimethyl fumarate in cakes and49kinds of pesticide residues in plant-based foods.The main researches are as follows:A simple, stable and sensitive ECL sensor was developed based on tris(2,2-bipyridyl)ruthenium(II) immobilized on the surface of a Pt wire with Nepem-105D ion exchange solution. It contains only two Pt wires and a matrass. Under optimal conditions, six repeat injections of0.3μg ml-1OFL solution was3.6%and the inter-day precision was6.8%on three consecutive days. The sensor was used as a detector of HPLC. In this HPLC-ECL system, luminescence reagent Ru(bpy)32+was immobilized and can be reused, therefore, no Ru(bpy)32+delivery system is needed, the experimental setup was simplified. There is no post column reagent addition, which would dilute analytes, potentially leading to chromatographic band-broadening. Furthermore, the reagent cost and its contamination to the environment were reduced. The HPLC-ECL was used for the determination of multiple target fluoroquinolone residues in milk and three antiemetic drugs in human serum successfully.A sensitive and robust electrogenerated chemiluminescence (ECL) flow sensor was developed in this work. It was based on Ru(bpy)32+immobilized with Nepem-211membrane, which has good electrical conductivity, and high exchange capacity for immobilization of Ru(bpy)3+. The flow sensor has good stability. The precision of11repeat injections of8.0ngμL-1erythromycin,4.0ngμL-1clarithromycin solutions were1.40%and1.76%, respectively. The proposed flow sensor has been used as a post-column detector in HPLC for determination of erythromycin and clarithromycin in honey and pork and doxepin, amitriptyline, and clomipramine in human urine.A method of one step rapid extraction of dimethyl fumarate in cakes using acetonitrile and n-hexane saturated each other was established. Dimethyl fumarate and fat impurities can be extracted by acetonitrile and n-hexane, respectively, at the same time. This pre-treatment method is simple, rapid and reliable. GC-ECD was used to analyze dimethyl fumarate of food at the first time in this study. Furthermore, it was compared with GC-FID and CG/MS, the sensitivity of GC-ECD method is higher than GC-FID method.A method for rapid determination of49kinds of pesticide residues in plant-based foods by GC/MS was established. The pesticide residues in vegetable samples and dry plant-based foods were extracted with acetonitrile and acetone, respectively. The extracting solution was clean-up by SPE after being concentrated.286vegetable samples,30edible mushrooms and35tea bags were analyzed in three consecutive years. The pesticides residue in tea bags, leafy vegetables and fresh edible mushrooms were higher than dry edible mushrooms. According to GB2763-2012, the pesticides level of2.10%vegetables exceeded maximum residue limits.更多还原