节点文献

液相萃取新方法的建立和应用

The Establishment and Application of New Liquid Extraction Method

【作者】 吴昊

【导师】 杜黎明;

【作者基本信息】 山西师范大学 , 无机化学, 2012, 博士

【摘要】 分析化学中一个重要的研究方向就是建立快速,准确和灵敏的分析方法。尽管现在发明了许多先进的仪器设备能够对生物样品、环境样品和药物制剂中的分析物进行直接测定,但是样品的前处理-萃取通常也是必不可少的步骤,通过萃取步骤可以将分析物从复杂样品中分离和富集出来,从而建立灵敏度和高选择性好的分析方法。大多数的分析仪器是无法直接处理复杂样品的,所以样品前处理步骤也就成为分析方法中不可缺少的重要环节,因此开发快速简便的样品前处理方法一直都是分离富集研究领域中的热门课题。本论文以分析化学和分离科学为研究背景,研究了表面活性剂和离子液体作为绿色萃取剂对一些药物和食品添加剂的萃取能力,以荧光和高效液相色谱作为检测手段进行了测定,分别建立了高灵敏度的药物制剂、生物体液、中草药及食品中分析物的荧光光谱和高效液相色谱新方法,本论文研究的内容和结果共分六个部分:1.对浊点萃取和离子液体微萃取方法的原理进行了介绍。综述了这两种方法与各种分析手段结合用于测定各类无机和有机化合物的研究进展。评述了浊点萃取和离子液体萃取现有方法存在的优缺点。2.采用非离子表面活性剂PONPE 7.5和阴离子表面活性剂十二烷基硫酸钠混合表面活性剂进行浊点萃取,对该混合表面活性剂从水溶液中萃取氧氟沙星和加替沙星的能力进行了研究。该方法采用电解质NaCl使混合表面活性剂产生浊点现象,继而进行分离后用荧光光谱测定。对影响萃取的pH值、表面活性剂用量、电解质用量、浊点温度及萃取时间等各种因素进行了研究。在最佳条件下,氧氟沙星和加替沙星的线性范围分别为0.1150和0.1250 ng ml-1,检出限分别为0.04和0.06 ng ml-1。将该方法应用于药物制剂,加标尿样和血浆中这两种药物的测定,其准确度和精密度令人满意。3.采用荧光分光光度法研究了盐酸哌唑嗪在阴离子表面活性剂中的光谱行为,发现使用阴离子表面活性剂凝聚固相微萃取对盐酸哌唑嗪的富集因子很高,在此基础上建立了一种阴离子表面活性剂固相微萃取荧光分光光度法测定盐酸哌唑嗪的新方法。阴离子表面活性剂十二烷基硫酸钠会在水溶液中形成胶束溶液,当加入MgCl2之后会产生分散均匀的固相,将该溶液离心分离后用乙醇将富集相定容,通过荧光进行测定。该方法具有对分析物富集率高、操作简便、灵敏度高和选择性好的优点。可以用于药物制剂和生物样品中盐酸哌唑嗪的测定。4.对小檗碱、巴马汀、药根碱和黄连碱在离子液体中的荧光光谱进行了研究,发现离子液体能使这些药物荧光显著增强,其中[C8MIM][PF6]对他们荧光的增强为最大。进一步研究发现,这些药物能够采用温度辅助离子液体扩散液相微萃取法被[C8MIM][PF6]从水溶液中萃取出来,其富集因子和萃取率分别为83.3和98.5%、98.1%、98.3%和98.8%,基于离子液体[C8MIM][PF6]能够富集,分离和增敏这四种药物荧光这一现象,提出了一种灵敏度高和选择性好的从水溶液中富集和测定这四种药物的新方法。在最佳条件下,线性范围分别为0.8~130 ng/mL、0.9~160 ng/mL、0.7~140 ng/mL和0.6~110 ng/mL,检出限分别为0.089 ng/mL、0.112 ng/mL、0.124 ng/mL和0.099ng/mL。该方法已成功应用于测定药物制剂,尿样和血样中的这些药物。5.将离子液体原位溶剂形成微萃取法与高效液相色谱联用,测定了博落回和白屈菜中的血根碱和白屈菜红碱,黄连和黄柏以及中成药中的小檗碱、巴马汀和黄连碱。当把一定量的离子对试剂KPF6加入到含有水溶性的离子液体溶液中后,生成了可以作为萃取剂的非水溶离子液体[C6MIM][PF6],这一离子液体可以替代易挥发有机溶剂进行萃取。对影响萃取效率的多种因素进行了研究,比如离子液体的类型和体积、KPF6的用量、样品的pH值、萃取时间和离心时间进行了优化。实验结果表明该方法可以应用于测定中草药及中成药中的这几种生物碱。6.建立了一种新颖和简单的微萃取方法,该方法是基于手动震荡离子液体扩散液相微萃取测定六种合成食品色素,如柠檬黄、苋菜红、日落黄、诱惑红、胭脂红和赤藓红。采用高效液相色谱紫外检测器测定了这些合成色素。与已报道的离子液体扩散液液微萃取方法相比较该过程不需要扩散溶剂,加热,超声波或额外的化学试剂。这种方法是将[C8MIM][BF4]通过手晃动的方法完全扩散到水溶液中,加速了被分析物从水相中传质到离子液体中的传质过程。对影响萃取过程的因素进行了详细研究,如离子液体体积、样品pH、萃取时间和离心时间等。在最佳实验条件下,该方法有非常好的灵敏度,检出限为0.015–-0.32 ng mL-1。该方法已成功应用于食品样品的测定,加标回收的范围在95.8–104.5%之间。

【Abstract】 In recent years, the development of fast, precise, accurate andsensitive methodologies has become an important issue. However,despite the advances in the development of highly efficientanalytical instrumentation for the end-point determination ofanalytes in biological and environmental samples andpharmaceutical products, sample pre-treatment is usuallynecessary in order to extract, to isolate and to concentrate theanalytes of interest from complex matrices because most of theanalytical instruments cannot directly handle the matrix. A samplepreparation step is therefore commonly required. Based on theanalytical chemistry and separation science, the ability ofsurfactants and ionic liquids as green extractant for extractionsome drugs and food additives was studied. Fluorescence and highperformance liquid chromatography as the means of detection weredetermined. The high sensitivity fluorescence and high performanceliquid chromatography methods for the analysts in pharmaceuticalpreparations, biological fluids, herbal medicines and food wereestablished. The contents of this paper are as follows:(1) The principle of the methods of cloud point extraction andionic liquid micro-extraction was introduced. Reviewed these twomethods combined with variety of analytical tools for the determination of various inorganic and organic compounds.Advantages and disadvantages of existing methods of cloud pointextraction and ionic liquid extraction have been introduced.(2) A cloud-point extraction process using mixed micelle of theanionic surfactant sodium dodecyl sulfate and the nonionicsurfactant polyoxyethylene(7.5)nonylphenylether to extract twofluoroquinolone antimicrobial agents ofloxacin and gatifloxacinfrom aqueous media was investigated. The method is based on themixed micelle-mediated extraction of fluoroquinolones in thepresence of NaCl electrolyte as an inducing phase separation, thenspectrofluorimetric determination. The effect of different variablessuch as pH, PONPE7.5 concentration, SDS concentration, sodiumchloride concentration, cloud point temperature and time wasinvestigated and optimum conditions were established. At theoptimum conditions, the rectilinear calibration graphs wereobtained in the concentration range 0.1150 and 0.1250 ng ml-1ofofloxacin and gatifloxacin and the limits of detection was 0.04 and0.06 ng ml-1, respectively. The proposed procedures were appliedsuccessfully for the determination of the investigated drugs in theirpharmaceutical dosage forms, spiked urine and spiked plasmasamples with a good precision and accuracy.(3) The fluorescence spectral behavior of Prazosin Hydrochloridein anionic surfactant has been studied, and maximum extractionefficiency was observed. Accordingly, a method for thedetermination of Prazosin Hydrochloride using anionic surfactantSodium dodecyl sulfate (SDS) by fluorescence spectrometry aftercoacervation cloud point extraction was proposed. Under optimum conditions, Prazosin Hydrochloride was separated andpreconcentrated owing to the formation of stable micelle in thepresence of SDS. After phase separation, the surfactant-rich phasewas diluted with ethanol, and then determined by fluorescence. Theproposed method is simple, sensitive, and selective, and has a highenrichment factor, the method was successfully applied for thedetermination of the drug in pharmaceutical preparations and urine.(4) The fluorescence spectrum of berberine, palmatine,jatrorrhizine and coptisine in ionic liquids were studied, found thattheir fluorescence significant increased in ionic liquids and[C8MIM][PF6] could make the most increased of fluorescence.Further studies showed that these drugs could be extracted fromaqueous by [C8MIM][PF6] used the method of temperature-assistedionic liquid dispersive liquid phase microextraction and theenrichment factor and extraction recovery was 83.3 and 98.5%,98.1%, 98.3% and 98.8% respectively. Based on the [C8MIM][PF6]preconcentraton, separation and sensitized fluorescence for thesedrugs, a new selective and sensitive method for the determinationof the concentration of these four drugs in aqueous samples ispresented. At the optimum conditions, the linear relationship wasobtained i n the range were 0.8-130, 0.9-160, 0.7-140 and 0.6-110 ngmL-1, with a detection limit were 0.089, 0.112, 0.124 and 0.099 ngmL-1, respectively. The proposed method was successfully appliedfor the determination of the drug in pharmaceutical preparations,urine and serum samples.(5) An efficient in situ solvent formation microextraction (ISFME)combining high performance liquid chromatography was developed for the determination of sanguinarine and chelerythrine in Macleayacordata (Willd.) R. Br. and Chelidonium majus L and berberine,palmatine, and coptisine in medicinal plants and pharmaceuticalpreparations. The amount of ion-pairing agent (KPF6) was added tothe sample solution containing a water-miscible ionic liquid([C6MIM][Br]) to obtain a hydrophobic ionic liquid ([C6MIM]PF6),which acted as the extraction phase to replace volatile organicsolvent as an extraction solvent. Several important parametersinfluencing the extraction efficiency of IL-ISFME such as the typeand volume of IL, amount of KPF6, sample pH, extraction time,centrifugation time were optimized. The experimental resultsindicated that the proposed method was successfully applied to theanalysis of these alkaloids in medicinal plants and pharmaceuticalpreparations(6) A novel and simple microextraction method is introducedbased on manual shaking ionic liquid dispersive liquid phasemicroextraction (MS-IL-DLLME) for the determination of sixsynthetic food colorants such as Tartrazine, Amaranth, SunsetYellow, Allura Red, Ponceau 4R, Erythrosine. High performanceliquid chromatography coupled with UV detector was used for thedetermination of synthetic food colorants. The procedure is no needfor a dispersive solvent, heating, ultrasonic or additional chemicalreagents, in contrast to conventional IL-DLLME. In this method1-octyl-3-methylimidazolium tetrafluoroborate ([C8MIM][BF4]) wasdispersed into the aqueous sample solution as fine droplets bymanual shaking, and which promoted the analytes more easilymigrate into the ionic liquid phase. Some effective factors such as the volume of [C8MIM][BF4], sample pH, extraction time,centrifuging time have been investigated in detail. Under theoptimum experimental conditions, the proposed method hadexcellent detection sensitivity with limits of detection (LOD, S/N = 3)in the range of 0.015–0.32 ng mL-1. This method has been alsosuccessfully applied to analyze the real food samples and goodspiked recoveries over the range of 95.8–104.5% were obtained.

节点文献中: 

本文链接的文献网络图示:

本文的引文网络