固相微萃取-高效液相色谱联用技术的进展

固相微萃取（SPME）技术是近年来发展起来的一种无溶剂,集采样、萃取、浓缩、进样于一体的样品预处理新技术,它与同效液相色谱技术的联用已受到人们的瞩目;该文评述了SPME-HPLC联用技术的进展,并展望这一技术的应用前景。     

Applications of solid‐phase micro‐extraction with mass spectrometry in pesticide analysis

Pesticides, widely applied in agriculture, can produce a variety of transformation products and their continuous use causes deleterious effects to ecosystem. Efficient and sensitive analytical techniques for enrichment and analysis of pesticides samples are highly required. Compared with other extraction methods, solid‐phase micro extraction is a solvent free, cost effective, robust, versatile, and high throughput sample preparation technique, especially for the analysis of pesticides from complicated matrices. Coupling of solid‐phase micro extraction with gas chromatography and mass spectrometry and liquid chromatography–mass spectrometry has been extensively applied in pesticide analysis. On the other hand, in recent years, combination of fast separation using solid‐phase micro extraction and rapid detection using ambient mass spectrometry is providing highly efficient pesticide screening. This article summarizes the applications of solid‐phase micro extraction coupled to mass spectrometry for pesticides analysis.     

固相微萃取技术的进展及其在食品分析中应用的现状

固相微萃取(SPME)是当今色谱分析中使用极为广泛的样品前处理方法,这一技术将萃取、浓缩、解吸、进样等功能集于一体,灵敏度高且操作简便。该文简要介绍了近年来SPME涂层、装置及相应技术的演变,综述了SPME在国内外食品分析中的应用现状,并讨论了国内部分研究者在采用这一技术进行定量分析时存在的一些共性问题。     

Application of solid-phase microextraction in analytical toxicology

Solid-phase microextraction (SPME) is a miniaturized and solvent-free sample preparation technique for chromatographic–spectrometric analysis by which the analytes are extracted from a gaseous or liquid sample by absorption in, or adsorption on, a thin polymer coating fixed to the solid surface of a fiber, inside an injection needle or inside a capillary. In this paper, the present state of practical performance and of applications of SPME to the analysis of blood, urine, oral fluid and hair in clinical and forensic toxicology is reviewed. The commercial coatings for fibers or needles have not essentially changed for many years, but there are interesting laboratory developments, such as conductive polypyrrole coatings for electrochemically controlled SPME of anions or cations and coatings with restricted-access properties for direct extraction from whole blood or immunoaffinity SPME. In-tube SPME uses segments of commercial gas chromatography (GC) capillaries for highly efficient extraction by repeated aspiration–ejection cycles of the liquid sample. It can be easily automated in combination with liquid chromatography but, as it is very sensitive to capillary plugging, it requires completely homogeneous liquid samples. In contrast, fiber-based SPME has not yet been performed automatically in combination with high-performance liquid chromatography. The headspace extractions on fibers or needles (solid-phase dynamic extraction) combined with GC methods are the most advantageous versions of SPME because of very pure extracts and the availability of automatic samplers. Surprisingly, substances with quite high boiling points, such as tricyclic antidepressants or phenothiazines, can be measured by headspace SPME from aqueous samples. The applicability and sensitivity of SPME was essentially extended by in-sample or on-fiber derivatization. The different modes of SPME were applied to analysis of solvents and inhalation narcotics, amphetamines, cocaine and metabolites, cannabinoids, methadone and other opioids, fatty acid ethyl esters as alcohol markers, γ-hydroxybutyric acid, benzodiazepines, various other therapeutic drugs, pesticides, chemical warfare agents, cyanide, sulfide and metal ions. In general, SPME is routinely used in optimized methods for specific analytes. However, it was shown that it also has some capacity for a general screening by direct immersion into urine samples and for pesticides and other semivolatile substance in the headspace mode.     

Determination of chemical warfare agents and related compounds in environmental samples by solid-phase microextraction with gas chromatography

Solid phase microextraction (SPME) is an increasingly common method of sample isolation and enhancement. SPME is a convenient and simple sample preparation technique for chromatographic analysis and a useful alternative to liquid-liquid extraction and solid phase extraction. SPME is speed and simply method, which has been widely used in environmental analysis because it is a rather safe method when dealing with highly toxic chemicals. A combination of SPME and gas chromatography (GC) permits both the qualitative and quantitative analysis of toxic industrial compounds, pesticides and chemical warfare agents (CWAs), including their degradation products, in air, water and soil samples. This work presents a combination of SPME and GC methods with various types of detectors in the analysis of CWAs and their degradation products in air, water, soil and other matrices. The combination of SPME and GC methods allows for low detection limits depending on the analyte, matrix and detection system. Commercially available fibers have been mainly used to extract CWAs in headspace analysis. However, attempts have been made to introduce new fiber coatings that are characterized by higher selectivities towards different analytes of interest. Environmental decomposition of CWAs leads to the formation of more hydrophilic products. These compounds may be isolated from samples using SPME and analyzed using GC however, they must often be derivatized first to produce good chromatography. In these cases, one must ensure that the SPME method also meets the same needs. Otherwise, it is helpful to use derivatization methods. SPME may also be used with fieldportable mass spectrometry (MS) and GC-MS instruments for chemical defense applications, including field sampling and analysis. SPME fibers can be taken into contaminated areas to directly sample air, headspaces above solutions, soils and water.     

Determination of furfural in beers,vinegars and infant formulas by solid-phase microextraction and gas chromatography/mass spectrometry

The solid-phase microextraction (SPME) technique with on-fibre derivatisation was evaluated for the analysis of furfural in infant formulas, beers, and vinegars. The poly(dimethylsiloxane)/divinylbenzene (PDMS/DVB) fibre was used and O-2,3,4,5,6-(pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA) was first loaded onto the fibre. Food sample of 2?mL was then placed in a 4?mL PTFE-capped glass vial. Headspace extraction by the SPME fibre was performed at 80°C for 20?min under 1100?rpm magnetic stirring with the addition of 40% sodium chloride. Afterwards, the SPME fibre was directly desorbed at the injection port of a gas chromatography/mass spectrometer (GC/MS), followed by the analysis of derivatives formed on-fibre. To avoid matrix interferences, standard addition method was performed. The adsorption-time profiles were examined. The precision, recovery and method detection limits (MDLs) were evaluated with spiked food samples. The relative standard deviations from different spiked samples were all less than 5% and the recoveries were 100?±?5%. With 2?mL of food sample, MDLs were in the range of 3.09?～?14.05?µg?L^?1. Compared with other techniques, the study shown here provided a simple, fast and reliable method for the analysis of furfural in food samples.     

食品中农药残留分析的样品前处理技术进展*

本文综述了近年来食品中农药残留分析的样品前处理技术,重点对超临界流体萃取法在食品农药残留分析中的应用及其联用技术进行了评述;同时对固相微萃取、微波辅助萃取和凝胶渗透色谱法进行了总结。对食物中农药残留分析技术的发展方向进行了讨论。     

Applications of solid-phase microextraction in food analysis

Food analysis is important for the evaluation of the nutritional value and quality of fresh and processed products, and for monitoring food additives and other toxic contaminants. Sample preparation, such as extraction, concentration and isolation of analytes, greatly influences the reliable and accurate analysis of food. Solid-phase microextraction (SPME) is a new sample preparation technique using a fused-silica fiber that is coated on the outside with an appropriate stationary phase. Analyte in the sample is directly extracted to the fiber coating. The SPME technique can be used routinely in combination with gas chromatography (GC), GC–mass spectrometry (GC–MS), high-performance liquid chromatography (HPLC) or LC–MS. Furthermore, another SPME technique known as in-tube SPME has also been developed for combination with LC or LC–MS using an open tubular fused-silica capillary column as an SPME device instead of SPME fiber. These methods using SPME techniques save preparation time, solvent purchase and disposal costs, and can improve the detection limits. This review summarizes the SPME techniques for coupling with various analytical instruments and the applications of these techniques to food analysis.     

Development and validation of a solid-phase microextraction method for the analysis of volatile organic compounds in groundwater samples

Summary Solid-phase microextraction is a relatively recent extraction technique for sample preparation. It has been used successfully to analyse environmental pollutants in a variety of matrices such as soils, water and air. In this work, a simple and rapid method for the analysis of volatile organic and polar compounds from polluted groundwater samples by SPME coupled with gas chromatography (GC) is described. Different types of fibres were studied and the extraction process was optimised. The fibre that proved to be the best to analyse this kind of samples was CAR-PDMS. The method was validated by analysis of synthetic samples and comparison with headspace—GC. The optimised method was successfully applied to the analysis of ground-water samples.     

Metabolic Evaluation of Urine from Patients Diagnosed with High Grade (HG) Bladder Cancer by SPME-LC-MS Method

Bladder cancer (BC) is a common malignancy of the urinary system and a leading cause of death worldwide. In this work, untargeted metabolomic profiling of biological fluids is presented as a non-invasive tool for bladder cancer biomarker discovery as a first step towards developing superior methods for detection, treatment, and prevention well as to further our current understanding of this disease. In this study, urine samples from 24 healthy volunteers and 24 BC patients were subjected to metabolomic profiling using high throughput solid-phase microextraction (SPME) in thin-film format and reversed-phase high-performance liquid chromatography coupled with a Q Exactive Focus Orbitrap mass spectrometer. The chemometric analysis enabled the selection of metabolites contributing to the observed separation of BC patients from the control group. Relevant differences were demonstrated for phenylalanine metabolism compounds, i.e., benzoic acid, hippuric acid, and 4-hydroxycinnamic acid. Furthermore, compounds involved in the metabolism of histidine, beta-alanine, and glycerophospholipids were also identified. Thin-film SPME can be efficiently used as an alternative approach to other traditional urine sample preparation methods, demonstrating the SPME technique as a simple and efficient tool for urinary metabolomics research. Moreover, this study’s results may support a better understanding of bladder cancer development and progression mechanisms.     

Solid-phase microextraction of chlorpyrifos in fruit samples by synthesised monolithic molecularly imprinted polymer fibres

A monolithic solid-phase microextraction (SPME) fibre was fabricated based on a molecularly imprinted polymer that could be coupled with gas chromatography for extraction, and determination of chlorpyrifos. The time of extraction, pH, temperature and ionic strength were investigated as important factors on the extraction procedure. The fabricated fibre was firm, inexpensive, stable and selective which gave it vital importance in SPME. The selectivity of the fabricated fibre in relation to analogue compounds was also investigated. Under the optimum conditions, the calibration curve was linear in the range of 1–20 mg L^?1 (R² = 0.9899). The high extraction efficiency was obtained for chlorpyrifos with a detection limit of 0.23 mg L^?1. The fabricated fibre was successfully applied to SPME of chlorpyrifos from apple and grape fruits after its extraction and followed by gas chromatography-flame ionisation detector analysis.     

Analysis of Explosives in Soil Using Solid Phase Microextraction and Gas Chromatography

Abstract

Current methods for the analysis of explosives in soils utilize time consuming sample preparation workups and extractions. The method detection limits for EPA Method 8330 for most analytes is substantially higher than the typical explosive concentrations encountered in soils near unexploded ordnance items, landmines, or other hidden explosive devices. It is desirable to develop new analytical techniques to analyze soil with low concentrations of explosives to support the development of explosive sensors. This report describes efforts to adapt headspace solid phase extraction and gas chromatography/mass spectrometry to provide a convenient and sensitive analysis method for explosives in soil.     

Headspace solid-phase micro-extraction and gas chromatography-ion trap tandem mass spectrometry method for butyltin analysis in sediments: Optimization and validation

In this work, headspace solid-phase micro-extraction (SPME) combined with gas chromatography-mass spectrometry (GC-MS) method for analysis of butyltin compounds in sediment samples was upgraded by the introduction of tandem mass spectrometry (MS/MS). Optimization and validation of this method based on an one step procedure, tetraethylborate in situ ethylation with simultaneous extraction by headspace SPME, combined with tandem mass spectrometry is described. A simple leaching/extraction step of mono-(M), di-(D) and tri-(T) butyltin (BT) compounds from the sediment is required as sample pre-treatment. The combination of the two techniques headspace SPME and MS/MS, led to very little matrix interference which permitted to attain limits of detection three or more orders of magnitude lower than those attained in previous methods: 0.3 pg g^− 1 for MBT, 1 pg g^− 1 for DBT and 0.4 pg g^− 1 for TBT. Linear response range was from 0.02–1260 ng g^− 1 for MBT, 0.07–1568 ng g^− 1 for DBT and 0.04–2146 ng g^− 1 for TBT and RSD < 15% was also obtained. The method was efficiently applied to a real sample sediment from Sado River estuary in Portugal, revealing the existence of BTs pollution, as the TBT level of 189 ± 15 ng g^− 1 was much higher than the maximum established as provisional ecotoxicological assessment criteria.     

Solid phase microextraction as a powerful alternative for screening of secondary metabolites in actinomycetes

Actinobacteria are one of the most promising producers of medically and industrially relevant secondary metabolites. However, screening of such compounds in actinobacteria growth demands simple, fast, and efficient extraction procedures that enable detection and precise quantification of biologically active compounds. In this regard, solid phase microextraction (SPME) emerges as an ideal extraction technique for screening of secondary metabolites in bacteria culture due to its non‐exhaustive, minimally invasive, and non‐destructive nature: its integrated sample preparation workflow; balanced coverage feature; metabolism quenching capabilities; and superior cleanup, as well as its versatility in configuration, which enables automation and high throughput applications. The current work provides a comparison of micro‐scale and direct immersion SPME (DI‐SPME) for screening of secondary metabolites, describes the optimization of the developed DI‐SPME method, and introduces the developed technique for mapping of target secondary metabolites as well as its direct coupling to mass spectrometry for such applications. The optimized DI‐SPME method provided higher amounts of extracted ions and intensity signals, yielding superior extraction and desorption efficiency as compared with micro‐scale extraction. Studied compounds presented stability on the coating for 24 h at room temperature. The DI‐SPME mapping approach revealed that lysolipin I and the lienomycin analog are distributed along the center and edges of the colony, respectively. Direct coupling of SPME to MS provided a similar ions profile as SPME‐LC‐MS while enabling a significant decrease in analysis time, demonstrating its suitability for such applications. DI‐SPME is herein presented as an alternative to micro‐scale extraction for screening of secondary metabolites in actinobacteria solid medium, as well as a feasible alternative to DESI‐IMS for mapping of biologic radial distribution of secondary metabolites and cell life cycle studies. Lastly, the direct coupling of DI‐SPME to MS is presented as a fast, powerful technique for high throughput analysis of secondary metabolites in this medium.     

固相微萃取-气相色谱/质谱法测定果汁及茶饮料中的10种光引发剂

建立了用固相微萃取结合气相色谱/质谱（GC/MS）检测13种果汁饮料和3种茶饮料中10种光引发剂的方法。通过正交试验筛选对萃取过程影响较大的因素,再通过单因素试验进一步优化,确定最佳的操作条件。样品经萃取后,在GC/MS进样口解吸3 min,经HP-5MS色谱柱分离,以选择离子方式监测,外标法定量。为消除基质的干扰,以样品基质加标做工作曲线,线性范围为0.3~60 μg/L,检出限为3~16 ng/L。分别对4个不同加标水平的样品平行测定5次,相对标准偏差均小于14.5%。对不同品牌、不同种类的16种盒装饮料进行了测定,所有样品中全部检出二苯甲酮,部分样品中检出对二甲氨基苯甲酸异辛酯、2-异丙基硫杂蒽酮、4-甲基二苯甲酮、1-羟基环己基苯基甲酮、2-氯噻吨酮。该方法操作简单、灵敏度高、无污染,可对10种光引发剂同时测定。该研究结果为从包装材料迁移至饮料中的光引发剂的测定提供了参考。     

多孔整体材料在固相微萃取中的应用研究进展

作为新型的样品前处理技术,固相微萃取由于具有操作简便、使用灵活、样品用量少、环境友好以及便于与分析仪器联用等优点而受到人们的广泛青睐。多孔整体材料具有通透性好、传质速度快、制备简单和易于改性等优点,目前被广泛用于包括样品前处理在内的诸多领域。文章结合作者的研究工作,对近几年整体材料在固相微萃取中的应用研究进行综述,并对其发展方向进行了展望。     

In vivo solid-phase microextraction in metabolomics: opportunities for the direct investigation of biological systems

Sample preparation has a strong impact on the quality of metabolomics studies. The use of solid-phase microextraction (SPME), particularly its in vivo format, enables the capture of a more representative metabolome and presents opportunities to detect low-abundance, short-lived, and/or unstable species not easily captured by traditional methods. The technique is ideally suited for temporal, spatial, and longitudinal studies of the same living system, as well as multicompartmental studies of the same organism. SPME is useful for the investigation of biological systems ranging in complexity from cells to mammalian tissues. Selected examples are highlighted in this Minireview in order to place the technique within the context of conventional methods of sample preparation for metabolomics.     

固相微萃取与高效液相色谱联用技术的进展

 较全面地评述了固相微萃取与高效液相色谱联用技术的发展与应用 ,包括该技术的原理、接口装置、涂层材料等。     

Development of Electro Solid-Phase Microextraction and Application to Methamphetamine Analysis

A new electro solid-phase microextraction (El-SPME) technique using homemade pencil-lead fibers has been developed as an effective means of selective extraction of methamphetamine before analysis by gas chromatography (GC) and gas chromatography–mass spectrometry (GC–MS). The methamphetamine was extracted by use of a laboratory-made El-SPME cell with three electrodes—the pencil-lead SPME fiber, Ag/AgCl, and platinum as working, reference, and auxiliary electrodes, respectively. A negative potential was applied to the homemade pencil-lead fiber during extraction. Experimental conditions, for example type of pencil-lead fiber, conditions for modification of the fiber, extraction time, applied potential, pH, and gas chromatographic conditions were optimized. Methamphetamine was identified by GC–MS. Screening of the extracted compounds showed that the proposed El-SPME technique is much more selective than direct SPME using a commercially available polyacrylate fiber. Under the optimum conditions the calibration plot for the compound was linear in the range 50–3,200 ng mL⁻¹ and the detection limit was 34 ng mL⁻¹.     

Automated analysis of geosmin, 2-methyl-isoborneol, 2-isopropyl-3-methoxypyrazine, 2-isobutyl-3-methoxypyrazine and 2,4,6-trichloroanisole in water by SPME-GC-ITDMS/MS

This paper describes a method of determining the following compounds in water characterised by complex matrices (raw waters and drinking waters): geosmin, 2-methylisoborneol (2-MIB), 2-isobutyl-3-methoxypyrazine (IBM), 2-isopropyl-3-methoxypyrazine (IPM) and 2,4,6-trichloroanisole (TCA). The method is carried out using headspace solid-phase microextraction (HS-SPME) combined with gas chromatography (GC) and ion trap mass spectrometry (ITMS). Several parameters of extraction and desorption were optimised through the use of a Combi PAL autosampler to automate various tasks (temperature extraction, extraction time, stir speed). Quantities of NaCl and the liquid volume/total volume ratio were also optimised. Double fragmentation (tandem MS/MS) was optimised on the target compounds. The method resulted in good linearity obtained for concentrations of 1 to 100?ng?L^?1 and provided detection limits of approximately below 1?ng?L^?1. Good precision (1–8%) was obtained. This method was successfully applied to the analysis of earthy and musty odours in municipal raw source waters with high concentrations of natural organic matter and in the corresponding treated waters. This is the first time MS/MS has been used to analyse odorous compounds in waters destined for human consumption. In addition, the method as developed is simple to use and lends itself to easy interpretation of chromatograms.