改良分散液—液微萃取的应用研究

发布时间：2018-03-14 00:53

本文选题：逆流盐析均匀液液萃取　切入点：分散液-液微萃取　出处：《河北大学》2017年硕士论文　论文类型：学位论文

【摘要】：随着科学技术的发展,利用分析仪器对样品的检测技术也在不断发展和进步。而样品预处理是样品进行测定过程中的重要步骤之一。传统的样品萃取技术存在操作费时费力、需要使用大量的毒性有机溶剂和样品等缺点,因此,发展省时、高效、减少有机溶剂的耗用量的样品前处理技术一直是分析化学研究的热点领域之一。目前,出现了多种新型预处理技术,如固相微萃取和液相微萃取,克服了传统方法中存在的问题。2006年,Assadi等人首次报道了一种新型样品预处理技术,即分散液-液微萃取(Dispersive Liquid-Liquid Microextraction,DLLME)。该技术以其操作简单、快速、耗费少、富集倍数高且对环境友好等优点,备受人们关注和欢迎,广泛应用于痕量分析样品测定领域。本文建立了3种新型样品预处理方法对环境样品分析物的测定。全文共包括四章,具体内容如下:第一章:绪论。对样品预处理方法进行了总结。重点介绍了分散液-液微萃取的研究现状、应用及发展趋势,同时阐述了本文的研究背景、选题思想和研究内容。第二章:本文提出了一种基于逆流盐析均匀液液萃取-分散液液微萃取结合智能手机比色法测定土壤中苯酚含量的方法。该方法中,首先,目标分析物经过衍生反应后,形成橙红色疏水性化合物,与乙腈和萃取剂1,1,2,2-四氯乙烷混合均匀转移至装填有NaCl固体小柱的窄管中,利用逆流盐析液液萃取使乙腈相和水相分离,将目标分析物萃取到有机相(包含乙腈和作为下一步分散液液微萃取的萃取剂)中;随后把上述乙腈相作为第二步分散液-液微萃取中的分散剂,对分析物进一步萃取;最后,利用智能手机比色法在一个可折叠自制的拍摄暗箱内完成对待测样品的测定。在优化的实验条件下,苯酚的浓度在9-400μg/L范围内有良好的线性关系,检出限(LOD,S/N=3)为2.7μg/L。该方法的加标回收率在85%-104%之间,方法操作简单、消耗少、分相快,并成功用于土壤中苯酚含量的测定。第三章:本文提出了一种基于固体预分散辅助分散液-液微萃取结合HPLC-UV分离和富集水中多环芳烃的方法。该方法中,先将萃取剂加入到适当量固体方糖上,此过程萃取剂完成了预分散,之后将固体加入样品溶液中,手动摇晃,使固体完全溶解,同时萃取剂分散到水样中,形成乳浊的溶液。经离心,完成对分析物的萃取,经氮气吹干复溶,最后采用HPLC-UV进行分离检测。此分散法不需要加入毫升级别的有机溶剂,仅凭借易溶、表面多孔的、可食用固体方糖即可完成对萃取剂的分散,该方法对环境友好、简便快速、易于操作,并成功用于水样中多环芳烃的测定。第四章:建立了一种基于悬浮固化可调节萃取剂原位分散液-液微萃取结合HPLC-UV测定蒽醌类药物的方法。该方法中以中链脂肪酸为萃取剂,将其溶于碱性溶液,之后注入酸性样品水溶液中调节萃取剂在溶液中存在状态,转换为疏水形式,完成对目标分析物的萃取过程。该方法是一种快速、简单、对环境友好的样品预处理技术。本实验考察了质子酸类型和用量、萃取剂用量、离子强度、离心时间对萃取效率的影响,并对该方法进行了系统评估。在优化的实验条件下,两种蒽醌类化合物在5-400 ng/mL浓度范围内有良好的线性关系,其相关系数均大于0.999,对实际样品进行了加标回收率实验,回收率在82%-110%范围内,准确度和精密度均得到了满意的结果。该萃取过程中并未使用有机分散溶剂,萃取时间短、操作简单、成本低、绿色环保。因此,该新型分散液-液微萃取在样品预处理中具有巨大潜质。
[Abstract]:With the development of science and technology, the use of analytical instruments on the sample detection technology is also in constant development and progress. The sample pretreatment is one of the most important steps in the process of determination of the samples. The existence of the traditional sample extraction technique is time-consuming, requires the use of large amounts of toxic organic solvents and samples and other shortcomings, therefore, the development of time, high efficiency, reduce consumption of samples of organic solvent pretreatment technology has been one of the hot spots in the field of analytical chemistry research. At present, there are many new pretreatment technology, such as solid phase microextraction and liquid phase microextraction, to overcome the existing problems in the traditional method of.2006, Assadi et al reported for the first time a new sample processing technology, namely dispersive liquid-liquid microextraction (Dispersive Liquid-Liquid, Microextraction, DLLME). The operation is simple, rapid, less cost, high number of times and enrichment of environmental protection Good attention and welcome, widely used in trace analysis determination of field samples. This paper established 3 new sample pretreatment methods for determination of analytes in environmental samples. The thesis consists of four chapters, the specific contents are as follows: the first chapter: introduction. The sample pretreatment methods are summarized. The key is introduced the research status of DLLME, application and development trend, and expounds the research background of this paper, research ideas and research content. The second chapter: This paper presents a method based on uniform salting out countercurrent liquid-liquid extraction and dispersive liquid liquid for determination of phenol in soil colorimetric micro extraction combined with intelligent mobile phone. In this method, firstly, analysis after derivatization reaction after the goal, the formation of orange red hydrophobic compounds, and acetonitrile and extraction agent 1,1,2,2- four chlorine ethane mixed evenly transferred to the narrow tube filled with solid column in NaCl, Salting out by countercurrent liquid-liquid extraction to acetonitrile and aqueous phase separation, the target analytes extracted into organic phase (extractant containing acetonitrile and as the next step of dispersed liquid-liquid microextraction); then the acetonitrile phase as the second step of DLLME in dispersing agent for further analyte extraction; finally, the use of intelligent mobile phone colorimetry in a folding homemade shooting box determination completed within the sample to be measured. Under the optimized experimental conditions, the phenol concentration has a good linear relationship in the range of 9-400 g/L, the detection limit (LOD, S/N=3) and the recovery is 2.7 ~ g/L. of the method the rate between 85%-104% method has advantages of simple operation, less consumption, fast phase, and was successfully used to determine the content of phenol in soil. The third chapter: This paper proposes a method based on solid dispersion assisted dispersive liquid-liquid microextraction combined with HPLC-UV separation and enrichment of PAHs in water Aromatics method. In this method, the extraction agent is added to the appropriate amount of solid sugar, the extractant completed pre dispersion after the solid is added to the sample solution, manual shaking, the solid is completely dissolved, at the same time solvent dispersed into water. The solution to form emulsion. After centrifugation, complete the extraction of the analyte, dried by nitrogen and dissolved, and finally HPLC-UV was separated and detected. The organic solvent dispersion method doesn't need to add the ml level, only by virtue of soluble, porous surface, solid dispersion can be completed on the edible sugar extraction agent, this method is simple and rapid, environmentally friendly, easy to operate, and for the determination of polycyclic aromatic hydrocarbons in water samples. The fourth chapter: the establishment of a suspension based on curing adjustable extractant in situ dispersive liquid-liquid microextraction combined with HPLC-UV method for the determination of anthraquinone drugs. This method in medium chain fatty acid for extraction The agent, which is dissolved in the alkaline solution after injection, extraction agent regulating state in the solution of acid water solution samples, converted to hydrophobic form of target analyte extraction process. This method is a rapid, simple, the sample pretreatment technology of friendly environment. The effects of acid type and the amount of proton, amount of solvent, ionic strength, the influence of centrifugal time on extraction efficiency, and the method of the evaluation system. Under the optimized experimental conditions, two kinds of anthraquinone compounds have a good linear relationship in the concentration range of 5-400 ng/mL, the correlation coefficient is greater than 0.999, the actual samples the recovery test, the recovery rate is in the range of 82%-110%, the accuracy and precision of the results are satisfactory. The extraction process does not use organic solvent dispersion, short extraction time, simple operation, low cost, green environmental protection Therefore, the new dispersing liquid liquid microextraction has great potential in the sample pretreatment.

【学位授予单位】：河北大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O658.2

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