【作者】 刘芳；

【导师】 闫超；

【作者基本信息】 上海交通大学 ， 制药工程， 2012， 硕士

【摘要】 蒸发光散射检测器(Evaprate light scattering detector, ELSD)作为一种通用型检测器,不受物质本身结构的限制,适用于绝大多数不挥发和半挥发物质的分析检测,尤其在天然产物、药物、农残及食品分析领域更具优势。随着国内外天然产物、药物及食品安全分析的迅速发展,ELSD检测器也将逐步走向普及化。本论文由五部分组成,主要内容包括:第一部分介绍了选题的背景和意义,包括ELSD的原理和应用、加压毛细管电色谱-蒸发光散射器(pCEC-ELSD联用仪)的研究意义、食品添加剂甜味剂的应用现状以及分析方法研究进展。第二部分的工作主要建立了HPLC-ELSD同时检测食品中安赛蜜、糖精钠、甜蜜素、三氯蔗糖和阿斯巴甜5种甜味剂的方法,此方法可用于食品安全检测。甜味剂经0.1% (v/v)甲酸缓冲液提取后,利用C18固相萃取小柱净化浓缩,以3μm C18柱为分离柱,0.1% (v/v)甲酸(氨水调节pH=3.5)-甲醇为流动相,经HPLC-ELSD分离检测。结果表明,5种甜味剂在30μg/mL - 1000μg/mL的质量范围内,具有良好的线性关系(相关性系数大于0.997);在3个添加水平下,样品的平均回收率85.6% - 109.0%,相对标准偏差小于4.0%;方法最低检出限(LOD, S/N=3)介于2.5-10μg/mL之间。该方法简单、灵敏且操作成本低,可用于不同形态食品中多种甜味剂的同时检测。第三部分的工作主要是建立了HILIC-ELSD同时检测无糖食品中赤藓糖醇、木糖醇、山梨糖醇、麦芽糖醇和乳糖醇5种糖醇的方法,采用超声提取样品中的糖醇,以3μm Amide-80亲水反应色谱柱作为分离柱,乙腈-水为流动相,经HILIC-ELSD分离检测。结果表明,5种糖醇在0.05-5 mg/mL的范围内,具有良好的线性关系(相关性系数大于0.998);在3个添加水平下,样品的平均回收率为92.5% - 99.7%,相对标准偏差小于3.9%;方法最低检出限(LOD, S/N=3)介于0.01-0.02 mg/mL之间。同样表明,该方法简单、灵敏且操作成本低,可用于无糖食品中多种糖醇含量的测定。第四部分主要介绍了加压毛细管电色谱(pressurized capillary electrochromatography, pCEC)与蒸发光散射检测器的联用,由于加压毛细管电色谱流速一般低于微升级/分钟,而传统蒸发光散射检测器是适用于流速为毫升级/分钟的常规液相色谱,所以需要通过对ELSD雾化、蒸发、检测单元及联用接口等关键技术的研究,实现ELSD与pCEC的联用。本部分工作主要是对加压毛细管电色谱与蒸发光散射检测器联用后系统的性能测试,以葡萄糖样品的检测限、重复性、线性做为考察指标,检测限为1 ng,峰面积的RSD%在0.91% - 2.84%范围内,线性范围在两个数量级左右。同时应用加压毛细管电色谱联用蒸发光散射检测器分离了3种氨基酸和5种甜味剂标准品,以考察其对混合样品的分离检测性能。另外,在第二章对甜味剂的研究基础上,建立了应用此联用技术检测蜜饯食品中的安赛蜜、糖精钠、甜蜜素3种磺胺类甜味剂的方法,分析速度较常规液相色谱快,试剂及样品消耗量少,方法简单方便且结果可靠。更多还原

【Abstract】 Evaporative light scattering detection (ELSD) as a common detection, with the advantage of not to be limited by the substance structure, is suitable for analysis of most volatile and semi-volatile materials. The detection is commonLy used in the area of natural product, medicine, pesticide residues and food satety and analysis. With the rapid development of analysis of natural product, medicine and food safety, ELSD will become more popular.This thesis is divided into five parts as follows:The first chapter briefly introduced the background and significance of the thesis, including the theory and application of ELSD, the significance of the research of pressurized capillary electrochromatography- evaporative light-scattering detector (pCEC-ELSD), current application and analytical method of food additives.In the second chapter, a high performance liquid chromatographic method with evaporative light scattering detection (HPLC-ELSD) which was used in the determination of food safety, has been developed for the simultaneous determination of five synthetic sweeteners (acesulfame-K, saccharin sodium, sodium cyclamic, sucralose and aspartame) in food. The procedure involves an extraction of the five sweeteners with a 0.1% (v/v) formic acid buffer solution, sample clean-up and pre-concentration using solid phase extraction cartridges (SPE) and finally, separation on a C18 column (3μm) using 0.1% (v/v) formic acid buffer (adjusting to pH=3.5 with aqueous ammonia solution) / methanol as mobile phase, then analysis and determination with HPLC–ELSD. The results showed that the reasonable linearity was achieved for all the analytes over the range of 0.6μg -20μg with the correlation coefficients r > 0.997. The trueness of the method was satisfactory with recoveries ranging from 85.6%-109.0% at three spiked concentrations, with the relative standard deviations (RSD) lower than 4.0%. The limits of detection (LOD, S/N=3) were between 0.05μg -0.2μg. It is a simple, sensitive and low cost method, and the established method has been successfully applied to the simultaneous determination of five synthetic sweeteners in food.In the third chapter, a method using hydrophilic interaction liquid chromatography with evaporative light scattering detection (HILIC-ELSD) was developed for the simultaneous determination of five sugar alcohol (Erythritol, Xylitol, Sorbitol, Maltitol and Lactitol) in suger-free food. We used TOSHO TSK gel Amide-80 3μm column (4.6 mm ID×15 cm), with water and acetonitrile as the mobile phase in isocratic elution, determination with ELSD. The results showed that the reasonable linearity was achieved for all the analytes over the range of 1μg-100μg with the correlation coefficients r>0.998. The trueness of the method was satisfactory with recoveries ranging from 92.5%-99.7% at three spiked concentrations, with the relative standard deviations (RSD) lower than 3.9%. The limits of detection (LOD, S/N=3) were between 0.2μg-0.4μg. It was a simple, sensitive and low cost method, which could be applied to the simultaneous determination of sugar alcohol in sugar-free food.The last chapter mainly introduce the pressurized capillary electro- chromatography ( pCEC) coupled with ELSD. Since the flow of the mobile phase in pCEC is below 1μL/min and ELSD is a detection fit for the common HPLC with a flow in the mL/min, the commonly used ELSD for HPLC needs to be mofified, such as the mofification of nebulization, evaporation, detection section, interface and so on. The last chapter is mainly focused on the system evaluation of pCEC-ELSD. With the LOD, repeatbility, linearity of glucose as major parameters. The results showed that the LOD is 1 ng, the RSD% of peak area of glucose is between 0.91%-2.84, linearity range is about 2 orders of magnitude. We separated 3 amino acids and 5 sweeteners standards with the pCEC-ELSD system. A method using pCEC-ELSD was also developed for the simultaneous determination of three sulfonamides sweeteners, with the advatages of high analysis speed and lower consumption of reagent and sample.更多还原