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solid phase extraction of Trace Copper（Ⅱ） Using Octadecyl Silica Membrane Disks Modified with N,N′-Disalicylideneethylenediamine

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Chinese Journal of Chemistry 2007年第12期25卷 1842-1848页

作者： MOGHIMI, Ali Department of Chemistry Varamin Campus Islamic Azad University Varamin Iran

A simple and reproducible method for the rapid extraction and determination of trace amounts of copper（Ⅱ） ions using octadecyl-bonded silica membrane disks modified by N,N′-disalicylideneethylenediamine （DESDA） and atomic absorption spectrometry was presented. The method is based on complex formation on the surface of the ENVI-18 DISK^TM disks followed by stripping of the retained species by minimum amounts of appropriate organic solvents. The elution is efficient and quantitative. The effects of potential interfering ions, pH, ligand amount, stripping solvent, and sample flow rate were also investigated. Under the optimal experimental conditions, the break-through volume was found to about be 1000 mL providing a preconcentration factor of 500. The maximum capacity of the disks was found to be （389±4） μg for Cu^2＋. The limit of detection of the proposed method is 5 ng per liter. The method was applied to the extraction and recovery of copper in different water samples.

关键词： Copper(Ⅱ) solid phase extraction octadecyl slica disks atomic absorption spectrometry N,N′-disalicylideneethylenediamine

solid phase extraction of methomyl and thiodicarb from environmental water with an activated carbon cartridge and their determination by HPLC

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Journal of Environmental Sciences 2000年第1期12卷 100-104页

作者： Chen, Yan-Jun Lu, Ying-Hua Liu, Jun Chen, Ya-Min Department of Chemistry Jining Medical College Shandong Jining 272113 China

A solid phase extraction procedure of methomyl and thiodicarb from environmental water was presented. This method utilizes a 40—60 mesh activated carbon cartridge and high performance liquid chromatography (HPLC). The 40—60 mesh activated carbon works faster and yield higher adsorption efficiency. Detection limits of methomyl and thiodicarb in environmental water are 0 1 μg/L and 0 2 μg/L, respectively. Average recoveries of fortified methomyl and thiodicarb in water are in the range of 90 7%—98 8% and 88 9%—103 6%, respectively. The relative standard deviations are lower than 7%. This method is simple, rapid, accurate and precise.

关键词： HPLC solid phase extraction activated carbon methomyl thiodicarb CLC number: X592 Document code: A

Determination of 4-tert-octylphenol in surface water samples of Jinan in China by solid phase extraction coupled with GC-MS

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Journal of Environmental Sciences 2013年第8期25卷 1712-1717页

作者： Xueyu Yang Mingren Liu Zhongpeng Wang Qian Li Zhaoliang Zhang School of Chemistry and Chemical Engineering University of Jinan School of Resources and Environment University of Jinan

Octylphenols, considered as xenoestrogens, mainly exist as 4-tert-octylphenol （OP） in aquatic environments. The high stability and accumulation of OP in aquatic systems have caused endocrine disruption. The OP in surface water in Jinan, China was analyzed by gas chromatography-mass spectrometry （GC-MS） coupled with solid phase extraction （SPE）. Water samples were extracted by SPE on a cartridge system containing C-18 as sorbent. To increase sensitivity and selectivity, OP was derivatized to 4-tert-octyl-phenoxy silane. With the use of phenanthrene-d10 as internal standard, the detection limit based on signal-to-noise ratio （S/N = 3） was 0.06 ng/mL. The average recovery was from 84.67% to 109.7%. The precision of the method given as the relative standard deviations （RSD） was within the range 6.24%-12.96%. In the target water samples, the concentrations of OP were as follows： 15.88-71.24 ng/L for Jinxiuchuan Reservoir, 3.850-26.68 ng/L for the city moat, 6.930-41.56 ng/L for Daming Lake, 66.03-474.2 ng/L for Xiaoqing River, 14.66-17.72 ng/L for the Yellow River, and 10.60-26.43 ng/L for Queshan Reservoir. The Xiaoqing River was seriously polluted due to the discharge of wastewater from Jinan. Jinxiuchuan Reservoir had a higher concentration of OP compared with the Yellow River and Queshan Reservoir, which is ascribed to the surrounding human activities. These data are reported for the first time, providing strong support for the control of OP pollution in Jinan.

关键词： GC-MS octylphenol Jinan solid phase extraction derivatization internal standard

Development trend and prospect of solid phase extraction technology

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Chinese Journal of Chemical Engineering 2022年第2期35卷 245-255页

作者： Chao Zhang Huifang Xing Liangrong Yang Pengfei Fei Huizhou Liu National Science Library Chinese Academy of SciencesBeijing 100190China College of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China Department of Library Information and Archives ManagementSchool of Economics and ManagementUniversity of Chinese Academy of SciencesBeijing 100190China Key Laboratory of Green Process and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China

solid phase extraction is widely used in sample pretreatment,concentration and analysis processes due to high selectivity and suitability for low concentration sample *** this review,we systematically summarized and discussed the development trends of solid phase extraction by bibliometrics *** analyzing papers output scale,the research and development direction of solid phase extraction technology is *** also give an overview on current strategies of novel solid phase extraction from the separation medium and separation *** paper aims to describe the global research profile and the development trends of solid phase extraction,to help researchers to accurately grasp the research trend and to provide support for scientific research institutions to formulate scientific policies and strategic ***,the prospect of the development and application of solid phase extraction is also discussed.

关键词： solid phase extraction Papers output scale Quality of research Novel technology

Characterization of seawater and aerosol particle surfactants using solid phase extraction and mass spectrometry

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Journal of Environmental Sciences 2021年第10期33卷 164-174页

作者： Tret C.Burdette Amanda A.Frossard Department of Chemistry University of Georgia140 Cedar StreetAthensGA30606USA

Surface-active organic molecules(surfactants)may influence the ability of an aerosol particle to act as a cloud condensation nuclei by reducing its surface *** source of organic mass in aerosol particles,which may also contain surfactants,is bubble bursting on the sea *** order to directly compare these molecules in the ocean and aerosol particles,we developed a method using multiple solid phase extractions and high resolution mass spectrometry to characterize surface active organic molecules in *** method has extraction efficiencies greater than 85%,75%,and 60%for anionic,cationic,and nonionic surfactant standards,*** this study,we demonstrate the presence of three ionic classes of surface active organics in atmospheric aerosol particles and estuarine water from Skidaway Island,*** this extraction method,organic molecules from both estuarine water and atmospheric aerosol particles significantly reduced surface tension of pure water(surface tension depression of~18 m N/m)and had high ratios of hydrogen to carbon(H/C)and low ratios of oxygen to carbon(O/C),indicative of *** previous work has observed a larger fraction of anionic surface active organics in seawater and marine aerosol particles,here we show cationic surface active organics may make up a large fraction of the total surface active molecules in estuarine water(43%–47%).

关键词： solid phase extraction Organic aerosol particles Marine organics Mass spectrometry Surfactants

Synthesis and solid phase extraction Performance Study of NNAL-specific Molecularly Imprinted Polymers Using Dummy Templates

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Chinese Journal of Chemical Physics 2013年第3期26卷 361-368,I0004页

作者：张志丹郑赛晶杨俊王维妙刘百战朱晓兰中国科学技术大学化学系合肥230026 中国烟草总公司卷烟烟气重点实验室上海200082

Dummy molecularly imprinted polymers （DMIPs） for 4-（methylnitrosamino）-1-（3-pyridyl）-1-butanol （NNAL） were produced using three structural analogues as dummy template molecules. The chosen analogues were 4-（acetymethylamino）-1-（3-pyridyl）-butanol, 4- （methylamino）-1-（3-pyridyl）-1-butanol, and 1-（3-pyridyl）-1,4,-butanediol. The molecular recognition characteristics of the produced polymers were evaluated by X-ray photoelec- tron spectroscopy （XPS） and Fourier transform infrared spectroscopy （FT-IR）. Interactions between NNAL and methacrylic acid should be cooperative hydrogen bonds while the ni- trogen atom of the pyridine ring and the oxygen atom of the nitroso group in NNAL are two of the hydrogen-bond acceptors. It was further demonstrated that DMIP synthesized by 4-（acetymethylamino）-1-（3-pyridyl）-butanol had the best binding performance by XPS and FT-IR. Then dummy molecularly imprinted solid phase extraction （DMISPE） was developed for the determination of the analyte using the hit polymer as the sorbing material. Under optimal conditions, the recovery of NNAL dissolved in standard solution reached 93%. And the investigated polymer exhibited much higher binding of NNAL when nicotine was acted as the competitive molecule. Also the proposed method was applied to the measurement of NNAL spiked in blank urine samples with recoveries ranging from 87.2% to 101.2%.

关键词： Molecularly imprinted polymer Dummy template 4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanol solid phase extraction

Selective Pre-concentration and solid phase extraction of Mercury（Ⅱ） from Natural Water by Silica Gel-loaded （E）-N-（1-Thien-2＇-ylethylidene）-1,2-phenylenediamine phase

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Chinese Journal of Chemistry 2007年第10期25卷 1536-1541页

作者： MOGHIMI, Ali Department of Chemistry Varamin Campus Islamic Azad University Varamin Iran

Silica gel-loaded （E）-N-（1-thien-2＇-ylethylidene）-1,2-phenylenediamine （TEPDA） phase was synthesized based on physical adsorption approaches. The stability of a chemically modified TEPDA especially in concentrated hydrochloric acid that was then used as a recycling and preconcentration reagent allowed the further uses of silica gel-loaded immobilized TEPDA phase. The application of this silica gel-loaded phase to sorption of a series of metal ions was performed by using different controlling factors such as the pH of the metal ion solution and the equilibration shaking time by the static technique. This difference was interpreted on the basis of selectivity incorporated in these sulfur containing silica gel-loaded TEPDA phases. Hg（Ⅱ） was found to exhibit the highest affinity towards extraction by these silica gel-loaded TEPDA phases. The pronounced selectivity was also confirmed by the determined distribution coefficients （Kd） of all the metal ions, showing the highest value reported for mercury（Ⅱ） extraction by the silica gel immobilized TEPDA phase. The potential applications of the silica gel immobilized TEPDA phase to selective extraction of mercury（Ⅱ） from aqueous solution were successfully accomplished and preconcentration of low concentration of Hg（Ⅱ）（30 pg·mL^-1） from natural tap water with a preconcentration factor of 200 for Hg（Ⅱ） off-line analysis was conducted by cold vapor atomic absorption analysis.

关键词： silica gel (E)-N-(1-thien-2'-ylethylidene)-1,2-phenylenediamine (TEPDA) solid phase extraction

Comparison of Different Cartridges of solid phase extraction for Determination of Polyphenols in Tobacco by UPLC/MS/MS and Multivariate Analysis

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Chemical Research in Chinese Universities 2011年第4期27卷 550-556页

作者： ZHANG Xia LIU Wei XU Yong YANG Liu KONG Wei-song RUI Xiao-dong YANG Shuai CHEN Yong-kuan MIAO Ming-ming Key Laboratory of Tobacco Chemistry Yunnan Academy of Tobacco Science Kunming 650106 P. R. China Research and Development Center of Hongta Tobacco（Group） Corporation Limited Yuxi 653100 P. R. China

The comparison of solid phase extraction（SPE） for the preconcentration and isolation of polyphenols in tobacco samples was carried out by ultra-high performance liquid chromatography/tandem mass spectrometry （UPLC/MS/MS） and multivariate *** adsorbing materials of SPE（C18,NH2,SAX and OASIS） were *** was found that the C18 and OASIS cartridges can not only speed up the purification process,but also simplify the SPE operation.A UPLC/MS/MS was used for the determination of polyphenols in tobacco samples after *** analytes were separated and determined in *** limit of detection was 0.05 ng/*** analysis（CA） and principal component analysis（PCA） were used for the analysis of 4 varieties（flue-cured tobacco,oriental tobacco,sun-cured tobacco and burley） in order to interpret the effect of planting and machining process on the concentration of *** different types of tobacco samples could be easily clustered by *** on the chemical composition of tobacco resulted in two principal components（PCs） that take 84.2% of the total *** PCA and CA indicate that the polyphenols can be used for distinguishing tobacco types.

关键词： solid phase extraction Polyphenol Ultra-high performance liquid chromatography/tandem mass spectro-metry(UPLC/MS/MS) Tobacco Cluster analysis Principal component analysis

Modified Activated Carbon as solid phase extraction Adsorbent for the Preconcentration and Determination of Trace As（Ⅲ） in Environmental Samples by Graphite Furnace Atomic Absorption Spectrometry

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Chinese Journal of Chemistry 2012年第3期30卷 665-669页

作者： Tavakkoli,Nahid Habibollahi,Saeed Amini Tehrani,Shahla Department of Chemistry Payame Noor University19395-4697 TehranIran

A simple and selective method was developed for the preconcentration, separation, and determination of trace amounts of As（Ⅲ） in an aqueous solution by solid phase extraction combined with graphite furnace atomic absorption spectrometry. Activated carbon （AC） was modified by sodium diethyldithiocarbamate （NaDDTC） and then used as a new, stable and easily prepared solid sorbent in a mini column for the extraction of As（Ⅲ） in aqueous solution. Factors influencing the sorption and desorption of As（Ⅲ）, such as volume and concentration of eluent, sam- ple pH, flow rate and effect of interfering ions on the recovery of As（Ⅲ） have been systemically investigated. At pH 2.0 As（Ⅲ） could be adsorbed quantitatively by NaDDTC-AC, and then eluted completely with 2 mL of 3.0 moloL 1 HNO3. The amount of eluted As（Ⅲ） was measured using graphite furnace atomic absorption spectrometry. The detection limit of As（Ⅲ） was 0.04 ng·mL-1 with enrichment factor of 100 and the relative standard deviation （RSD, n=8） was 1.58% at 10 ng·mL-1 level.

关键词： activated carbon preconcentration arsenic solid phase extraction adsorption graphite furnace atomicabsorption spectrometry