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用于磷酸酯和甲基膦酸酯类化合物测定的固相微萃取新型涂层 总被引:1,自引:0,他引:1
以羟基硅油和二乙烯基苯为涂层材料 ,采用溶胶 凝胶技术和自由基引发交联的方法制备了一种新型的固相微萃取探头。采用顶空固相微萃取与气相色谱联用的方法模拟检测了水中磷酸酯和甲基磷酸酯类化合物。与商品化固相微萃取探头相比 ,该新型涂层可获得高的萃取效率。甲基膦酸二甲酯、磷酸三甲酯和磷酸三丁酯的最低检测限分别为 0 34,2 2 0和 0 0 1mg/L,相对标准偏差为 3 6 7%~ 6 4 4 % ,线性范围为 1~ 2个数量级 ,方法重现性好 ,回收率为 89 4 6 %~ 90 88%。 相似文献
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羟基聚甲基苯基硅氧烷固相微萃取纤维的制备及在蔬菜中农药残留分析的应用 总被引:2,自引:0,他引:2
通过合成羟基聚甲基苯基硅氧烷(PMPS-OH)材料,制备固相微萃取(SPME)纤维涂层.通过与商品化聚二甲基硅氧烷(PDMS)、聚丙烯酸酯(PA)和PDMS/聚二乙烯基苯(DVB)纤维对六六六异构体(α,β,γ,δ-BHC)、DDT及其衍生物(p,p′-DDD,p,p′-DDE,o,p′-DDT,p,p′-DDT)、联苯菊酯、甲氰菊酯、高效氟氯氰菊酯、三氟氯氰菊酯、氯氰菊酯和氰戊菊酯等选定农药萃取效果的比较,所制备的PMPS-OH纤维具有更好的萃取效率.对SPME实验条件进行了研究和优化,测定方法对各种农药的线性范围多在0.01~2 ng/g之间,相应的检出限在0.001~0.05 ng/g范围,回收率在50.5%~103%.方法已被应用于蔬菜样品中农残的检测. 相似文献
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溶胶-凝胶法制备SE-54固相微萃取探针 总被引:4,自引:0,他引:4
固相微萃取(SPME)是一种样品制备技术。用来对样品中的有机分子进行富集萃取,已被广泛应用于痕量分析。然而,市售的SPME石英探针的表面涂渍层的最高允许使用温度只有270℃,实际在温度达200℃时固定相已经明显流失。其使用寿命只有40~100次。这是由于较厚的涂层用自由基引发固定 相似文献
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Nafion涂层固相微萃取探头的制备 总被引:6,自引:2,他引:4
采用Nafion作为固相涂层在不锈钢丝上涂制了固相微萃取 (SPME)探头 ,研究了它的特性 ,并与类似商品探头作了比较。该探头具有萃取量大、可比商品探头 (SPME)的富集率高 1个数量级 ,灵敏度高、寿命长、且不易折断等特性。由于Nafion有很强的极性 ,因此它对极性化合物有很强的萃取能力 ,适合萃取醇等物质。用该探头测定了醇类物质 ,检出限达 2 0~ 60ng·ml-1,相对标准偏差RSD <5 %。 相似文献
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用于固相微萃取的乙烯基开链冠醚复合涂层的研制 总被引:2,自引:0,他引:2
固相微萃取 (SPME)是一种新型的样品预处理技术 [1] ,其核心是 SPME装置中萃取头上的固相涂层 .目前商用 SPME涂层的种类较少 ,热稳定性较差 (推荐使用温度 2 0 0~ 2 80℃ ) ,使用寿命较短(40~ 1 0 0次 ) ,价格偏高 ,限制了其推广应用 .因此发展高选择性、高稳定性和高效的固 相似文献
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Preparation and investigation of polymethylphenylvinylsiloxane-coated solid-phase microextraction fibers using sol-gel technology 总被引:7,自引:0,他引:7
Summary Poly(methylphenylvinylsiloxane) (PMPVS) coating was first prepared using sol-gel technology and applied for solid-phase microextraction
(SPME). The extraction properties of the novel coating for volatile and semi-volatile organic compounds were investigated
using a homemade SPME device coupled with GC-FID. The porous surface structure of the coating provided high surface area and
allowed for high extraction efficiency. Compared with commercial SPME stationary phase, the new phase showed better selectivity
and sensitivity toward the various analytes, due to their inherent multifunctional properties and the features of sol-gel
chemistry. Furthermore, PMPVS coating showed good thermal stability and long lifetime. 相似文献
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Headspace solid-phase microextraction (HS-SPME) and gas chromatography with flame photometric detection (GC-FPD) have been
investigated for determination of butyltin and octyltin stabilizers in poly(vinyl chloride) (PVC) products. The organotin
stabilizers were first released from the plastic matrix by dissolving the PVC sample in tetrahydrofuran (THF). The stabilizers
were then hydrolyzed to the chloride forms, by treatment with 6 mol L−1 HCl, then derivatized with sodium tetraethylborate (NaBEt4) in 0.2 mol L−1 sodium acetate buffer (pH 4.5) at 50 °C. HS-SPME was performed with a fused-silica fiber coated with a 100-μm film of polydimethylsiloxane
(PDMS). The collected organotin compounds were then desorbed in the GC injector at 280 °C and analyzed by GC-FPD. Linearity
(r≥0.994) over a concentration of approximately two orders of magnitude was usually obtained. Limits of quantitation (LOQ) of
the four organotin compounds studied, viz., monobutyltin (MBT), dibutyltin (DBT), monooctyltin (MOT), and dioctyltin (DOT),
were in the range 0.3–1.0 ng Sn mL−1. Recovery was >90% for butyltins and >80% for octyltins. The method was validated by analyzing two reference standard PVC
sheets with known organotin content. The applicability of the method to analysis of organotin stabilizers in commercial PVC
products was also demonstrated. 相似文献
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A new cold fiber solid-phase microextraction device was designed and constructed based on thermoelectric cooling. A three-stage thermoelectric cooler (TEC) was used for cooling a copper rod coated with a poly(dimethylsiloxane) (PDMS) hollow fiber, which served as the solid-phase microextraction (SPME) fiber. The copper rod was mounted on a commercial SPME plunger and exposed to the cold surface of the TEC, which was enclosed in a small aluminum box. A heat sink and a fan were used to dissipate the generated heat at the hot side of the TEC. By applying an appropriate dc voltage to the TEC, the upper part of the copper rod, which was in contact to the cold side of the TEC, was cooled and the hollow fiber reached a lower temperature through heat transfer. A thermocouple was embedded in the cold side of the TEC for indirect measurement of the fiber temperature. The device was applied in quantitative analysis of off-flavors in a rice sample. Hexanal, nonanal, and undecanal were chosen as three off-flavors in rice. They were identified according to their retention times and analyzed by GC-flame ionization detection instrument. Headspace extraction conditions (i.e., temperature and time) were optimized. Standard addition calibration graphs were obtained at the optimized conditions and the concentrations of the three analytes were calculated. The concentration of hexanal was also measured using a conventional solvent extraction method (697+/-143ng/g) which was comparable to that obtained from the cold fiber SPME method (644+/-8). Moreover, the cold fiber SPME resulted in better reproducibility and shorter analysis time. Cold fiber SPME with TEC device can also be used as a portable device for field sampling. 相似文献
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A novel poly(3,4-ethylenedioxythiophene)-ionic liquid (i.e., 1-hydroxyethyl-3-methyl imidazolium-bis[(trifluoromethyl)sulfonyl]imide) composite film was electrodeposited on a Pt wire for headspace solid-phase microextraction. The film showed nodular structure and had large specific surface. In addition, it displayed high thermal stability (up to 300 °C) and durable property (could be used for more than 200 times). Coupled with gas chromatography-flame ionization detection, the resulting fiber was applied to the headspace solid-phase microextraction and determination of several alcohols (i.e., linalool, nonanol, terpineol, geraniol, decanol and dodecanol). It presented higher extraction capability in comparison with the poly(3,4-ethylenedioxythiophene) and commercial polydimethylsiloxane/divinylbenzene fiber. Under the optimized conditions, the linear ranges exceeded three magnitudes with correlation coefficients above 0.9952 and the low limits of detection were 34.2–81.3 ng L−1. For different alcohols the repeatabilities (defined as RSD) were <5.8% and <7.8% for single fiber (n = 5) and fiber-to-fiber (n = 4), respectively. The proposed method was applied to the determination of these alcohols in real samples with acceptable recoveries from 81.1% to 106.6%. 相似文献
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Hakkarainen M 《Journal of chromatography. A》2003,1010(1):9-16
A solid-phase microextraction (SPME) method was developed to quantitatively determine the amount of 6-hydroxyhexanoic acid in aqueous solutions. The SPME method in combination with GC-MS was then applied to identify and quantify the low-molecular-mass compounds migrating from a new poly(vinyl chloride) (PVC) material, PVC/polycaprolactone-polycarbonate (PCL-PC) during ageing in water. It was shown that only a small amount of 6-hydroxyhexanoic acid, the final hydrolysis product of PCL-PC, migrated from the blend during ageing at 37 and 70 degrees C. If, however, the temperature was raised to 100 degrees C rapid hydrolysis of PCL-PC resulted. In addition to 6-hydroxyhexanoic acid, 6-hydroxyhexanoic acid dimer, caprolactone, different carboxylic acids, acetophenone and phenol were identified. SPME-GC-MS was also applied to monitor the low-molecular-mass compounds migrating from the PVC/PCL-PC blend during thermo-oxidation. 相似文献
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Lijun Xie Shuqin LiuZhubing Han Ruifen JiangHong Liu Fang Zhu Feng ZengChengyong Su Gangfeng Ouyang 《Analytica chimica acta》2015
Metal-organic frameworks (MOFs) have received great attention as novel sorbents due to their fascinating structures and intriguing potential applications in various fields. In this work, a MIL-101(Cr)-coated solid-phase microextraction (SPME) fiber was fabricated by a simple direct coating method and applied to the determination of volatile compounds (BTEX, benzene, toluene, ethylbenzene, m-xylene and o-xylene) and semi-volatile compounds (PAHs, polycyclic aromatic hydrocarbons) from water samples. The extraction and desorption conditions of headspace SPME (HS-SPME) were optimized. Under the optimized conditions, the established methods exhibited excellent extraction performance. Good precision (<7.7%) and low detection limits (0.32–1.7 ng L−1 and 0.12–2.1 ng L−1 for BTEX and PAHs, respectively) were achieved. In addition, the MIL-101(Cr)-coated fiber possessed good thermal stability, and the fiber can be reused over 150 times. The fiber was successfully applied to the analysis of BTEX and PAHs in river water by coupling with gas chromatography–mass spectrometry (GC–MS). The analytes at low concentrations (1.7 and 10 ng L−1) were detected, and the recoveries obtained with the spiked river water samples were in the range of 80.0–113% and 84.8–106% for BTEX and PAHs, respectively, which demonstrated the applicability of the self-made fiber. 相似文献
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Solid-phase microextraction (SPME) is a convenient and efficient sampling technique recently applied to indoor air analysis.
We propose here a theoretical model of the adsorption kinetics of toluene on SPME fibre under static extraction conditions.
We discuss the effects of sampling volume and initial concentration of analyte on the adsorption kinetics. This model is used
to estimate the limits of detection taking into account operating conditions and to calculate theoretical calibration curves.
Results of comparison with experimental data are encouraging: only 11% difference for calibration curves and 30% for the estimation
of the limit of detection. On the basis of this kinetics model, the solid concentration gradient in the Carboxen coating was
modelled with Fick’s second law of diffusion in unsteady-state mass-transfer mode. Mass diffusion from the gas sample to the
SPME fibre was also investigated. It was shown that diffusion is the limiting step of the mass-transfer process in the static
mode. Thus, the model developed, allows a better understanding of adsorption on Carboxen fibre and in the future could be
a useful tool for cheap and time-saving development of SPME methods and the estimation of sampling performance.
Figure PDMS/Carboxen SPME fibre (scanning electron microscopy – magnification x 220) 相似文献
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In this paper, a novel graphene (G) based solid-phase microextraction (SPME) fiber was firstly prepared by immobilizing the synthesized G on stainless steel wire as coating. The new fiber possessed a homogeneous, porous and wrinkled surface and showed excellent thermal (over 330 °C), chemical and mechanical stability, and long lifespan (over 250 extractions). The SPME performance of the G-coated fiber was evaluated in detail through extraction of six pyrethroid pesticides. Although the thickness of G-coated fiber was only 6-8 μm, its extraction efficiencies were higher than those of two commercial fibers (PDMS, 100 μm; PDMS/DVB, 65 μm). This high extraction efficiency may be mainly attributed to huge delocalized π-electron system of G, which shows strong π-stacking interaction with pyrethroid pesticide. The G-coated fiber was applied in the gas chromatographic determination of six pyrethroids, and their limits of detection were found to be ranged from 3.69 to 69.4 ng L−1. The reproducibility for each single fiber was evaluated and the relative standard deviations (RSDs) were calculated to be in the range from 1.9% to 6.5%. The repeatability of fiber-to-fiber and batch-to-batch was 4.3-9.2% and 4.1-9.9%. The method developed was successfully applied to three pond water samples, and the recoveries were 83-110% at a spiking of 1 μg L−1. 相似文献
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Sakchaibordee Sungkaew Chongdee Thammakhet Panote Thavarungkul Proespichaya Kanatharana 《Analytica chimica acta》2010,664(1):49-80
A new polyethylene glycol fiber was developed for solid-phase microextraction (SPME) of styrene by electrodepositing porous Zn film on Ag wire substrate followed by coating with polyethylene glycol sol-gel (Ag/Zn/PEG sol-gel fiber). The scanning electron micrographs of fibers surface revealed a highly porous structure. The extraction property of the developed fiber-to-styrene residue from polystyrene packaged food was investigated by headspace solid-phase microextraction (HS-SPME) and analyzed with a gas chromatograph coupled with flame ionization detection (GC-FID). The new Ag/Zn/PEG sol-gel fiber is simple to prepare, low cost, robust, has high thermal stability and long lifetime, up to 359 extractions. Repeatability of one fiber (n = 6) was in the range of 4.7-7.5% and fiber-to-fiber reproducibility (n = 4) for five concentration values were in the range 3.4-10%. This Ag/Zn/PEG sol-gel fiber was compared to two commercial SPME fibers, 75 μm carboxen/polydimethylsiloxane (CAR/PDMS) and 100 μm polydimethylsiloxane (PDMS). Under their optimum conditions, Ag/Zn/PEG sol-gel fiber showed the highest sensitivity and the lowest detection limit at 0.28 ± 0.01 ng mL−1. 相似文献
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A novel solid-phase microextraction (SPME) fiber coating was prepared with siloxane-modified polyurethane acrylic resin by photo-cured technology. The ratio of two monomers was investigated to obtain good microphase separation structure and better extraction performance. The self-made fiber was then applied to organophosphorus pesticides (OPPs) analysis and several factors, such as extraction/desorption time, extraction temperature, salinity, and pH, were studied. The optimized conditions were: 15 min extraction at 25 °C, 5% Na2SO4 content, pH 7.0 and 4 min desorption in GC inlet. The self-made fiber coating exhibited better extraction efficiency for OPPs, compared with three commercial fiber coatings. Under the optimized conditions, the detection limits of 11 OPPs were from 0.03 μg L−1 to 0.5 μg L−1. Good recoveries and repeatabilities were obtained when the method was used to determine OPPs in ecological textile. 相似文献