固相微萃取

Abstract(#br)This study presents the preparation and the characterizations of six tri-metal centered metal-organic frameworks (tM-MOFs) as solid-phase microextraction (SPME) adsorbents. Possessing different proportions of Al, Ga and In atoms in their frameworks, the tM-MOF-based SPME coatings exhibited different extraction performance towards the organic pollutants. Extraction results showed that the M4 (Al 0.593 Ga 0.167 In 0.240 (O 2 C 2 H 4 )(h 2 fipbb)) coating exhibited the best enrichment ability among six tM-MOFs.

Abstract(#br)3D graphene-carbon nanotubes (G-CNTs) composite with unique morphology and structure was prepared by one-step insertion of CNTs into graphene. Subsequently, the G-CNTs composite as a fiber coating material for solid-phase microextraction (SPME) was fabricated on the surface of a stainless steel wire by direct coating method. The prepared coating was tested by the extraction of benzene homologues (BTEX, benzene, toluene, ethylbenzene and m-xylene).

Abstract(#br)The compositions of volatile compounds in headspace (HS) analyzed by a solid phase microextraction (SPME) sampling method usually differ from true compositions mainly because the partition coefficients for these compounds between headspace and a SPME fiber are not equal. In this paper we report an analytical strategy to more accurately quantify relative compositions of selected hydrocarbons present in gasoline residue by employing inverse gas chromatography (IGC) coupled with a HS-SPME sampling method.

Abstract(#br)Chocolate quality depends on the type of cocoa and how its manufacture was conducted. In this work, the analysis of the volatile fraction of the principal steps - from cocoa to chocolate - was performed. For this purpose, unroasted nibs, liquor and chocolate samples from five different places were used, and the isolation was conducted by HS-SPME (headspace solid phase microextraction) using a DVB/CAR/PDMS (divinylbenzene/carboxen/polydimethylsiloxane) fiber, lately desorbed in a homemade GC × GC chromatograph and detected by mass spectrometry.

Headspace solid-phase microextraction (SPME) with an 85 µm Carboxen polydimethylsiloxane (CAR/PDMS) fiber was used to extract volatile compounds, and a gas chromatograph equipped with a mass spectometry detector (GC-MS) was used to identify the volatile compounds in honeys. Thirty-four different volatile compounds from the headspace of honey produced in the central valley of Ñuble Province, Chile, were extracted with fiber coating CAR/PDMS. The identified compounds were: 10 alcohols, 9 acids, 6 ketones, 3 aldehydes, 2 furans, 2 terpenes and 2 lactones.

Electrospinning technique was used to convert polydimethyl siloxane (PDMS) sol-gel solution to a new nanostructure on a stainless steel wire. The surface morphology of the fiber was observed by scanning electron microscopy (SEM). It showed a diameter range of 30-60nm for PDMS nanoparticles with a homogeneous and porous surface structure. The applicability of this coating was assessed for the headspace SPME (HS-SPME) of benzene, toluene, ethylbenzene and xylenes (BTEX) from water samples followed by gas chromatography-mass spectrometry.

Headspace solid-phase microextraction (HS-SPME) combined with gas chromatography/mass spectrometry (GC/MS) method was applied for the investigation of low molecular weight volatile organic metabolites (VOMs) in pleural effusion samples. Three important HS-SPME experimental parameters that influence extraction efficiency (fiber coating, extraction time and temperature of sampling) were optimized by a univariate optimization design. The highest extraction efficiency was obtained when sampling was performed at 50°C for 10min under agitation using a carboxen/polydimethylsiloxane (CAR/PDMS) fiber.

Organophosphorus pesticides (OPPs), widely known as persistent organic pollutants, are the most popular contaminants in agriculture products in developing countries. The determination of OPPs in complex matrices, such as food, environmental and biological samples, usually requires extensive sample pretreatment. This review focuses on the sorptive extraction techniques applied as sample pretreatment for OPPs in complex matrices, including solid-phase extraction (SPE) and solid-phase microextraction (SPME).

摘要\n采用多固相微萃取( mSPME )结合热脱附-电喷雾电离/质谱( TD- ESI / MS )技术对水溶液中痕量分析物进行快速表征。同时使用一批市售SPME纤维(从2根到10根纤维)对溶液中的分析物进行萃取。然后将纤维捆绑在一个固定支架上，进行环境质谱分析。用10种聚丙烯酸酯( PA )包复的固相微萃取纤维萃取双酚A，结果线性良好( R2 = 0.9995 )，定量下限( \u003c 1ppb )。毫无争议的是，在较长的提取时间内，使用mSPME达到与使用单一SPME纤维相同的分析信号水平，需要较短的提取时间。采用mSPME-TD- ESI / MS快速检测聚碳酸酯( PC )婴儿奶瓶中的微量双酚A ( 4 - 20ppb )，并在1 min内完成分析。使用多种SPME纤维包复不同的材料，可以使不同类型的分析物在溶液中的浓度不同。采用聚酰胺( PA )和聚二甲基硅氧烷( PDMS )涂层纤维萃取同时检测布洛芬、双酚A ( BPA )和4 -正壬基酚( 4 -正壬基酚)。