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分散液相微萃取技术在液相色谱分析中的应用研究

The Applications of Dispersive Liquid-Liquid Microextraction on the High Performance Liquid Chromatographic Method

【作者】 韦彩云

【导师】 黄克靖;

【作者基本信息】 信阳师范学院 , 分析化学, 2010, 硕士

【摘要】 随着社会的进步,科学技术的发展,对现代分析技术也提出了更高的要求。不仅要求分析技术和分析仪器具有灵敏度高、检出限低、准确性好等特点,同时由于实际样品比较复杂,对样品前处理也提出了新的要求。高效、快速、价廉、绿色环保的样品制备与前处理技术的研究已成为现代分析化学研究的热门课题之一。分散液相微萃取(Dispersive Liquid-Liquid Microextraction, DLLME)是Assadi等在2006年首次报道的一种基于分散萃取的样品前处理新技术。此方法有机溶剂用量极少,使用10μL左右的萃取剂,通过分散剂让萃取剂和样品溶液形成均匀的混浊液使其接触面积增大,萃取离心后,被分析物富集到萃取剂中,取此有机相注入色谱进行分析测定。该方法富集倍数高、检出限低,同时具有操作简便、萃取时间短、相对标准偏差低等优势,受到研究者广泛关注。本文将分散液相微萃取和高效液相色谱-荧光检测(HPLC-FL)相结合,建立样品处理新方法,开展了实际样品中一些生物胺的分析检测,主要研究内容和创新点如下:1、分散液相微萃取与荧光衍生相结合,液相色谱分离荧光检测米酒中的三种生物胺(章胺、酪胺、苯乙胺)。荧光标记试剂N-羟基琥珀酰亚胺-2,6-二甲基喹啉-4-甲酸酯(DMQC-OSu)标记生物胺后,衍生产物用超声辅助分散液液微萃取,然后用高效液相色谱进行分离荧光检测。检出限在0.02-5 ng mL-1之间,日内和日间相对标准偏差分别在2.4-3.2%和3.2-5.5%之间。将该方法应用于米酒样品分析,加标回收率在96.7-99.5%范围内。2、生物胺(章胺、酪胺、苯乙胺)用荧光探针DMQC-OSu衍生后,以离子液体1-丁基-3-甲基咪唑六氟磷酸盐(C4MIMPF6)为萃取剂,超声辅助分散液液微萃取三种生物胺的衍生物,并用高效液相色谱分离荧光检测。检出限为0.0025-5ngmL-1(S/N= 3).回收率为90.2-116%。将该方法应用到啤酒样品中生物胺的检测,结果令人满意的。该方法用离子液体做为萃取剂,减少了传统有机溶剂的使用,加之离子液体难挥发及对无机物和有机物良好的溶解性,所以此方法对环境污染少,是一种比较绿色环保的新方法。

【Abstract】 With the progress of society, higher requirements put forward to modern analytical techniques. It not only needs analytical techniques and analytical instruments have high sensitivity, low detection limit and good accuracy and so on, but also put forward the new demands to sample pre-treatment. Development of High-performence, fast, low cost and environmental friendly sample preparation techniques has become one of the most popular topics of modern analytical chemistry.Dispersed liquid-liquid micro-extraction (DLLME) is a new sample pre-treatment technique base on distributed, first reported in 2006 by Assadi and co-workers. Only a small amount of solvent, just about little microlitre, is needed in concentrating analytes from aqueous samples. The mixture of extraction solvent and disperser solvent were injected into the sample solution by syringe, rapidly. Then the solution was centrifuged and the organic phase was aspirated into a microsyringe and injected into the HPLC system for analysis. The method is sensitive, simple, rapid, and has been used widely.In this paper, the sample pre-treatment technology dispersed liquid-liquid micro-extraction (DLLME) is coupled with high-performance liquid chromatography-fluorescence detection and was used for the extraction and determination of biogenic amines in real samples. The main content is listed as follows:1. Ultrasound-assisted dispersive liquid-liquid microextraction coupled with high-performance liquid chromatography-fluorescence detection was developed for the extraction and determination of three biogenic amines including octopamine, tyramine and phenethylamine in rice wine samples. Fluorescence probe 2,6-dimethyl-4-quinolinecarboxylic acid N-hydroxysuccinimide ester (DMQC-OSu) was applied for derivatization of biogenic amines. The LODs of biogenic amines were in the range of 5-0.02 ng mL-1. The intra-day precisions ranged from 2.4 to 3.2% and the inter-day precisions ranged from 3.2 to 5.5%. The proposed method was applied for the determination of biogenic amines in rice wine samples. The recoveries of the three amines ranged from 95.42 to 104.56% showed that the method was sufficiently applicable to determine biogenic amines in real samples. Therefore, it had the potential of practical applications and could be either a complementary or a parallel method for the biogenic amines determination.2. Room temperature ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate (C4MIMPF6) was used as extraction solvent, coupled with ultrasound-assisted dispersive liquid-liquid microextraction (UDLLME) for the extraction of three biogenic amines (octopamine, tyramine and phenethylamine). Fluorescence probe 2,6-dimethyl-4-quinolinecarboxylic acid N-hydroxysuccinimide ester (DMQC-OSu) was applied for derivatization of biogenic amines. The limits of detection ranged from 0.0025 to 5 ng mL"1 (S/N= 3). The recoveries ranged from 90.2 to 116%. The method was applied for the determination of biogenic amines in beer samples with satisfactory results. The use of ionic liquid involved some advantages such as the reduction of exposure to toxic solvent. Because of the negligible vapor pressure and good solubility for organic and inorganic compounds of the ionic liquids, the proposed method was environmentally friendly.

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