新型无溶剂样品制备方法—固相微萃取法

固相微萃取法（SPME）是在固相萃取（SPE）的基础上结合顶空分析（Headspace)建立起来的一种新型样品制备方法,具有简便,经济、不使用溶剂等优点,并且能做到提取、净化、浓缩和仪器分析同步完成,文中对固相微萃取的装置,原理、萃取条件等、特点,应用及SPME法今后可能发展的方向作以介绍和进行初步探讨。     

聚苯乙烯-丙烯酸乙酯新型固相微萃取吸附质的研究与应用

固相微萃取(SPME)是90年代兴起的新型无溶剂样品前处理技术,基本的固相微萃取是通过石英纤维头表面涂渍的高分子层对样品中的有机分子进行萃取和预富集,然后进行色谱分析,使预处理过程大为简化,提高了分析速度及灵敏度。目前,商品SPME．GC联用装置是由美国Supclco公司生产的涂有PDMS、PA、PEG20M3种单一吸附质及4种部分交联的复合固相材料。涂层极性决定了其应用范围。     

固相微萃取的发展近况

固相微萃取（SPME）是一种新型的样品预处理方法，随着对此技术发展的深入理解，新型SPME装置不断得到应用和发展。本文对其原理、装置、应用和发展的现状进行了综述。     

金属有机骨架衍生材料在样品前处理中的应用研究进展

样品前处理技术在复杂样品的整个分析过程中起着至关重要的作用,其不仅可以提高痕量目标物在样品中的浓度,而且能有效消除样品基质对分析的干扰。对于样品前处理技术而言,吸附剂是其最为核心部分。因此开发高效、稳定的新型吸附剂已成为前处理技术领域的研究热点。近年来,由金属有机骨架(metal-organic frameworks, MOFs)衍生的多孔材料因其形貌结构多样、孔径可调、比表面积高、热稳定性良好、耐化学腐蚀等优异性能,使其在样品前处理领域拥有广阔的应用前景,基于MOFs衍生材料的样品前处理新方法也层出不穷。然而,MOFs衍生材料仍存在MOFs前驱体合成工艺复杂、生产成本高、量产困难等问题。该文总结了近几年来MOFs衍生材料在分散固相萃取(dSPE)、磁固相萃取(MSPE)、固相微萃取(SPME)、搅拌棒固相萃取(SBSE)和分散微固相萃取(DMSPE)等样品前处理技术中的研究进展,并对多种MOFs衍生材料的制备方法、功能化调控、富集效率等方面进行了评述。最后,展望了MOFs衍生材料在该领域中的应用前景,为进一步研究MOFs衍生材料的应用提供了参考。     

固相微萃取-脉冲火焰光度法测定大气及水中的路易氏剂

建立了固相微萃取（SPME）与气相色谱/脉冲火焰光度检测器（GC／PFPD）联用测定大气和水中路易氏剂及其水解产物的方法。探讨了影响SPME萃取效率的萃取头类型、萃取时间、解吸时间等因素。优化了PFPD的条件参数、衍生化试剂及衍生条件。在优化的条件下，路易氏剂衍生产物的响应值与浓度有良好的线性关系。本方法对水中路易氏剂及其水解产物的检出限为0．1μg/L；气体中路易氏剂的检出限为10ng／m^3；水样的加标回收率为96．7％-102．1％；气体样品的加标回收率为94．9％-103．0％；RSD为2．06％。     

固相萃取-固相辅助衍生-气相色谱-串联质谱对水样和尿液中氰化物的分析检测

建立了一种针对氰化物的固相萃取-固相辅助衍生方法,结合气相色谱-串联质谱方法,实现了环境样本以及生物样本中痕量氰化物的定性及定量检测。首先采用氯胺T将氰根衍生为氯化氰,然后通过C8型固相萃取柱同时实现反应物的富集纯化和衍生化。对样品前处理条件进行优化,发现固相萃取柱的类型和衍生反应的溶剂环境是决定氰化物衍生效率的关键。分别采用气相色谱-电子轰击质谱（Gas chromatography-electron ionization/mass spectrometry, GC-EI/MS）及600 MHz核磁共振-氢谱（Proton nuclear magnetic resonance,1H-NMR）对产物进行分析,结果表明,衍生产物为硫氰酸正丁酯。基于此,以异丙基二硫醚为内标物,建立了水样及尿液中氰化物衍生产物的气相色谱三重四极杆-选择反应监测模式的定性及定量检测方法。在最优反应条件下对健康成年人（非吸烟组）及幼儿的尿液进行检测,发现尿液中含有内源性氰化物（浓度范围120～200 ng/mL）。本方法检测灵敏度高、专属性好且样品前处理时间短。对于水样和尿液中氰化物检测的线性范围分别为10～1...     

基于新型材料的固相微萃取探针的制备与应用

固相微萃取(SPME)是一种简便、快速、绿色的样品前处理方法,近年来引发了广泛关注。固相微萃取探针的萃取相对其萃取选择性和效率起着决定性作用,因此一系列物理化学性质优秀的新型固相微萃取涂层材料应运而生,被用于制备新型固相微萃取探针,以对不同样品基质中的有机小分子进行检测。本文概述了近年来新型SPME探针的研制所依托的新型材料,包括聚合物材料、碳材料、金属有机框架材料等,并重点阐述了相关材料的制备与固定方法、微观结构与萃取性能,以及所制备探针在环境分析、纺织品和皮革分析、食品分析等领域中的应用,并进一步对新型固相微萃取涂层今后的开发方向和应用前景进行了展望。     

采用溶胶-凝胶技术涂层的新型固相微萃取方法及其应用

将溶胶-凝胶技术应用于SPME固相涂层的制备,涂制的端羟基-聚二甲基硅氧烷固相涂层热稳定性好,萃取时间和解吸时间短,对极性化合物及非极性化合物均有较强的萃取富集能力。扫描电镜图显示涂层表面为多孔结构。采用该涂层的SPME方法在对环境样品的分析中获得了令人满意的效果。     

样品预处理与实时直接分析质谱的联用技术及应用

近年来,与实时直接分析质谱(DART-MS)相结合的样品预处理技术发展迅速,使得对复杂生物、环境、法医学、食品、个体小生物以及单细胞样品中的分析物进行直接分析成为可能。然而固体基质内部分析物检测困难、痕量分析物检测性能不佳已成为限制DART-MS进一步发展的关键问题。针对这些问题,多年来,研究人员在不同领域对样品预处理与质谱联用进行了多种尝试。该文以固相萃取(SPE)、分散固相萃取(DSPE)、搅拌棒吸附萃取(SBSE)、固相微萃取(SPME)、机械化学提取(MCE)和微波提取(MAE)等样品预处理技术为例,对不同研究领域中样品预处理技术与DART-MS联用的研究成果进行了综述,并对未来的发展趋势进行了展望。希望该综述能为开发与DART-MS联用的新型样品处理技术提供参考和帮助。     

SPME 涂层中硅烷化反应机理的研究

建立了SPME 涂层中硅烷化衍生化样品预处理方法,并用于葡萄酒中白黎芦醇的测定.SPME 硅烷化的反应动力学过程研究表明,涂层中硅烷化反应遵循假一级反应动力学,高温条件下硅烷化试剂会破坏极性聚丙烯酯(PA)涂层.     

The changing face of chemical derivatization in pharmaceutical and biomedical analysis

The present and past use of chemical derivatization reactions is overviewed with emphasis on the present role of derivatization in chromatographic and electrophoretic methods with special respect to fluorogenic derivatization to increase the selectivity and sensitivity, chiral derivatization to transform enantiomeric pairs to easily separable diastereomers, and GC/GC-MS derivatization. Non-chromatographic derivatization is also discussed with emphasis on UV-VIS spectrophotometry, fluorimetry, and immunoassay methods. The up-to-dateness of derivatization methods with negative examples mainly from the field of UV-VIS analysis are also discussed. Finally, examples are given on how the experiences obtained in the course of old studies can be used to solve current problems with the aid of chemical derivatization. Received: 19 January 1998 / Revised: 2 March 1998 / Accepted: 6 March 1998     

微波辅助衍生化GC-MS法测定食用油中的脂肪酸

利用微波技术,研究了用ＫＯＨ－甲醇,Ｈ２ＳＯ４－甲醇－甲苯、ＨＣｌ－甲醇等不同体系对食用油中的脂肪酸进行了衍生化,系统地比较了它们的优劣势,以及适合的分析对象,在１ｍｉｎ内完成衍生物生化反应,选用正庚烷代替传统方法的苯＋石油醚作为脂肪酸甲酯蝗提取剂,与传统消解及衍生化方法相比,具有节省溶剂,省时,易于操作等特点。     

The changing face of chemical derivatization in pharmaceutical and biomedical analysis

The present and past use of chemical derivatization reactions is overviewed with emphasis on the present role of derivatization in chromatographic and electrophoretic methods with special respect to fluorogenic derivatization to increase the selectivity and sensitivity, chiral derivatization to transform enantiomeric pairs to easily separable diastereomers, and GC/GC-MS derivatization. Non-chromatographic derivatization is also discussed with emphasis on UV-VIS spectrophotometry, fluorimetry, and immunoassay methods. The up-to-dateness of derivatization methods with negative examples mainly from the field of UV-VIS analysis are also discussed. Finally, examples are given on how the experiences obtained in the course of old studies can be used to solve current problems with the aid of chemical derivatization. Received: 19 January 1998 / Revised: 2 March 1998 / Accepted: 6 March 1998     

Field-amplified sample injection and in-capillary derivatization for sensitivity improvement of the electrophoretic determination of histamine

The feasibility of the combination of field-amplified sample injection (FASI) and in-capillary derivatization was explored for improving sensitivity of histamine in capillary electrophoresis (CE). Naphthalene-2,3-dicarboxaldehyde (NDA) was used as derivatization reagent. The reagent and sample was introduced by tandem mode. The derivatization was accomplished by at-inlet mode with standing time of 1.5 min. The combination of FASI and in-capillary derivatization was successfully achieved with about 400-fold concentration sensitivity enhancement compared to pre-capillary derivatization at the same set-up. The detection limit of concentration for histamine reached 1.25 x 10(-11) M by CE and fluorescence detection with S/N = 3. Parameters affecting FASI and in-capillary derivatization process including sample matrix, buffer concentration and reagent injection amount, were investigated.     

Enantioselective analysis of bambuterol in human plasma using microwave‐assisted chiral derivatization coupled with ultra high performance liquid chromatography and tandem mass spectrometry

In this study, an enantioselective analytical method based on microwave‐assisted chiral derivatization coupled with ultra high performance liquid chromatography and tandem mass spectrometry was developed for the determination of bambuterol enantiomers in human plasma. The chiral derivatization reaction was greatly accelerated by microwave irradiation. Under the optimized conditions, both the derivatization time and separation time on column was only 3 min, and the lower limit of quantification was 2.5 pg/mL. The recoveries were in the range of 90.1–93.0% without significant matrix effect. Compared with the conventional heating chiral derivatization, microwave‐assisted chiral derivatization obtained higher chiral derivatization yields with much shorter time due to the effect of microwave irradiation. Furthermore, the racemization during the derivatization reaction was systematically investigated. The results showed the concentration of acetic acid and the reaction time had significant effects on the racemization, which could be well controlled during microwave‐assisted chiral derivatization for the short reaction time. Finally, this novel approach was demonstrated by determining bambuterol in human plasma of a clinical pharmacokinetic study in eight healthy volunteers. On the basis of the results, microwave‐assisted chiral derivatization coupled with ultra high performance liquid chromatography and tandem mass spectrometry as a simple and effective enantioselective analysis technique for the determination of chiral drugs in complex biological samples showed great promise.     

微波消解同时衍生化GC-MS法测定血浆中脂肪酸的研究

研究了利用微波能对样品进行加热, 以Ｈ２ＳＯ４ － 甲苯－ 甲醇体系作衍生化试剂, 在消化的同时对血浆中的脂肪酸进行衍生化, 然后用ＧＣ－ ＭＳ 法测定血浆中脂肪酸。 对微波功率、微波加热时间、消解及衍生化试剂等条件进行了优化, 测定结果较好。该法整个消化及衍生化过程只需２ ｍｉｎ , 与传统方法相比大大缩短了实验操作时间, 特别适用于大量样品的测定。     

Towards a Non-Biased Formaldehyde Quantification in Leather: New Derivatization Conditions before HPLC Analysis of 2,4-Dinitrophenylhydrazine Derivatives

In leathers, formaldehyde is currently analyzed according to EN ISO 17226-1 standard, by reversed phase liquid chromatography after off-line precolumn derivatization with 2,4 dinitrophenylhydrazine (DNPH) in strong acidic conditions. We first demonstrate that this standard is not adapted to leather retanned with resins likely to release formaldehyde by hydrolysis. Indeed, formaldehyde content may be largely overestimated due to concomitant resin hydrolysis (in harsh acidic conditions) that releases formaldehyde during the derivatization step and during the waiting time on autosampler before analysis. Therefore, we thoroughly studied the derivatization step in order to propose new derivatization conditions. Replacing orthophosphoric acid by less acidic buffer solutions is not enough to avoid hydrolysis. A derivatization without adding acid is realized by solubilizing DNPH in acetonitrile instead of orthophosphoric acid. These conditions lead to a complete derivatization of formaldehyde in 3 h at 50 °C (in a water bath) while avoiding the hydrolysis of co-extracted dicyandiamide and melamine resins. The as-obtained leather extracts are stable over time. Formaldehyde contents found with this method agree with the formaldehyde content measured immediately at the end of derivatization reaction in standard conditions or with formaldehyde content measured by a home-designed flow injection analysis with acetylacetone online derivatization and UV detection.     

原位衍生化技术在液相色谱和液相色谱-质谱联用分析中的应用

衍生化是将待分析物转化为更适合的物质形式以便于分析的有效手段。原位衍生化技术作为一种常用的柱前衍生化方法,可以在样品基质中同时完成分析物的萃取和衍生化,具有高效、灵敏和选择性好的优点。原位衍生化结合其他前处理技术广泛用于胺类、醛酮类、醇类、酚类、羧酸和巯基化合物的分析中,在生物、药物、食品、环境、化妆品分析等领域有广泛的应用。该文概述了原位衍生化的反应类型和代表性衍生试剂,综述了原位衍生化技术在液相色谱和液相色谱-质谱联用分析中的应用,并展望其发展趋势。     

On-line redox derivatization liquid chromatography using double separation columns and one derivatization unit

A new on-line redox derivatization technique using double separation columns and one redox derivatization unit was presented for enhancement of separation selectivity of HPLC. This on-line redox derivatization HPLC system consisted of two separation columns and one redox derivatization unit placed between them. The redox reaction proceeds in the derivatization unit so that an analyte compound migrates as its original form in the first column, while as its oxidized or reduced form in the second column. The retention of the analytes is controlled by the lengths of the two separation columns in this system. We adopted a small column packed with porous graphitic carbon (PGC) as a redox derivatization unit and two C18 silica columns treated with hexadecyltrimethylammonium chloride as separation columns. The redox activity of PGC and the efficiency of the on-line redox derivatization HPLC system for enhancement of separation selectivity were investigated using EDTA complexes of some metal ions. Original untreated PGC and PGC treated with hydrogen peroxide completely oxidized Co(II)-EDTA and converted it to Co(III)-EDTA, while the other metal complexes eluted as their original oxidation states throughout the system. Selective separation and determination of cobalt in a reference copper alloy by the developed method were demonstrated.