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Chinese Chemical Letters 2008年第12期19卷 1487-1490页

作者： Shuai Hua Zhang Yuan Yuan Yang Dan Dan Han Chun Wang Xin Zhou Xiao Huan Zang Zhi Wang Key laboratory of Bioinorganic Chemistry College of Sciences Agricultural University of Hebei Baoding 071001 China

A new method for the determination of atrazine, simazine and prometryn in water samples by on-line sweeping concentration technique in micellar electrokinetic chromatography （MEKC） was developed. Various parameters affecting sample enrichment and separation efficiency were systematically studied. Compared with the conventional MEKC method, up to 60-200-fold improvement in concentration sensitivity was achieved in terms of peak height by using this sweeping injection technique. The compound strychnine was used as the internal standard for the improvement of the experimental reproducibility. The limits of detection （S/ N = 3：1） for atrazine, simazine and prometryn were 9, 10 and 0.5 ng mL-1, respectively. This method has been successfully applied to the analysis of atrazine, simazine and prometryn in lake, steam and ground water.

关键词： Triazine herbicides On-line concentration MEKC Sweeping Water samples

Hydrophilic Chitosan/Covalent Organic Framework Composites for Efficient Solid-Phase Microextraction of Polar Phenolic Compounds Prior to Gas chromatography: Mass Spectrometry Analysis

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Journal of Analysis and Testing 2024年第4期8卷 441-450页

作者： Haijuan Tao Jiale Liu Weikang Guo Qin Shuai Lijin Huang State Key laboratory of Biogeology and Environmental Geology Faculty of Materials Science and ChemistryChina University of Geosciences

Covalent organic frameworks （COFs） have been widely used to prepare solid-phase microextraction （SPME） coatings due to their large specific surface area and adjustable pore ***,the weak inherent hydrophilicity of COFs restricts their extraction performance for polar phenolic *** this work,COFs were combined with chitosan （CS） via Schiff base reaction to prepare novel SPME coating *** incorporation of CS,which contains abundant hydrophilic functional groups,eff ectively enhanced the hydrophilicity of the CS/COF composite,thus boosting its interaction affinity towards polar *** combination with gas chromatography—mass spectrometry （GC–MS）,an efficient and sensitive analytical method was *** optimal conditions,the developed method demonstrated a broad linear range(5.0–1.0×104ng/L,R2>0.9972),low detection limits （0.78–1.3 ng/L）,good reproducibility (relative standard deviations（RSDs）<8.8%),and excellent enrichment factors （5993–41,441）.Moreover,the established method was successfully applied to quantify phenolic compounds in grapes,and the recoveries ranged from 92.2%to 111%with RSDs of 2.3%–7.8%,meeting practical application *** study provides valuable insights into the efficient analysis and determination of trace polar contaminants in real samples.

关键词： Chitosan Covalent organic framework Hydrophilicity Solid-phase microextraction Trace phenolic compounds

A STOICHIOMETRIC DISPLACEMENT MODEL FOR RETENTION OF SOLUTE IN LIQUID chromatography WITH MULTI-COMPONENT SYSTEM

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Science China Chemistry 1992年第3期35卷 262-272页

作者：耿信笃边六交 laboratory of Modern Separation Science Department of Chemistry Northwest University Xi'an 710069 PRC

Considering all the kinds of interactions between solute and solvent, solute and stationary phase, solvent and stationary phase molecules as well as the competitional adsorption among various kinds of solvent molecules on the stationary phase, we present a stoichiometric displacement model of solute retention with four sets of parameters in liquid chromatography. This model was tested with data from both literature and experiments done by ourselves. These results show that this model may fit the experimental data for a liquid chromatography system with various kinds of mobile phases consisting of a complete range of multi-components and with different types of stationary phases.

关键词： high performance liquid chromatography retention model stoichiometric displacement multi-component system complete range of concentration.

Determination of Lignin in Marine Sediment Using Alkaline Cupric Oxide Oxidation-Solid Phase Extraction-on-Column Derivatization-Gas chromatography

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Journal of Ocean University of China 2013年第1期12卷 63-69页

作者： ZHANG Ting LI Xianguo SUN Shuwen LAN Haiqing DU Peirui WANG Min Key laboratory of Marine Chemistry Theory and Technology Ministry of Education Ocean University of China

Lignin serves as one of the most important molecular fossils for tracing Terrestrial Organic Matters （TOMs） in marine environment. Extraction and derivatization of lignin oxidation products （LOPs） are crucial for accurate quantification of lignin in marine sediment. Here we report a modification of the conventional alkaline cupric oxide （CuO） oxidation method, the modification consisting in a solid phase extraction （SPE） and a novel on-column derivatization being employed for better efficiency and reproducibility. In spiking blanks, recoveries with SPE for the LOPs are between 77.84% and 99.57% with relative standard deviations （RSDs） ranging from 0.57% to 8.04% （n=3）, while those with traditional liquid-liquid extraction （LLE） are from 44.52% to 86.16% With RSDs being from 0.53% to 13.14% （n=3）. Moreover, the reproducibility is greatly improved with SPE, with less solvent consumption and shorter processing time. The average efficiency of on-column derivatization for LOPs is 100.8%±0.68%, which is significantly higher than those of in-vial or in-syringe derivatization, thus resulting in still less consumption of derivatizing *** in the surface sediments sampled from the south of Yangtze River estuary, China, was determined with the established method. Recoveries of 72.66% to 85.99% with standard deviation less than 0.01mg/10g dry weight are obtained except for p-hydroxybenzaldehyde. The lignin content ∑8 （produced from 10g dry sediment） in the research area is between 0.231 and 0.587mg. S/V and C/V ratios （1.028 ± 0.433 and 0.192±0.066, respectively） indicate that the TOMs in this region are originated from a mixture of woody and nonwoody angiosperm plants; the high values or （Ad/Al）v suggest that the TOMs has been highly degraded.

关键词： lignin alkaline cupric oxide SPE on-column derivatization marine sediments

Optimization of multicomponent solvent selection in high-performance liquid chromatography using a statistical method

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Chinese Journal of Chemistry 1991年第3期9卷 222-230页

作者： WANG,Qin-Sun GAO,Ru-Yu WANG,Heng-Yan YAN,Bing-Wen National laboratory of Elemento-Organic Chemistry,Nankai University,Tianjin 300071 National laboratory of Elemento‐Organic Chemistry Nankai University Tianjin 300071

A computer-assisted method is presented for optimization of multicomponent solvent mobile phase selection for separation of O-ethyl-N-isopropyl phosphoro(thioureido)thioates in reversed-phase HPLC and four geometric isomers of pesticides Decis in normal-phase *** method is based on Snyder's solvent selection triangle concept using a statistical *** optimization of the separation over the experimental region is based on a special polynomial esti- mation from seven experimental runs,and resolution(R_s)is used as the selection *** agreement was obtained between predicted data and experimental results.

关键词： Optimization of multicomponent solvent selection in high-performance liquid chromatography using a statistical method high

A Sensitive Derivatization Method for the Determination of the Sugar Composition after Pre-column Reductive Amination with 3-Amino-9-ethylcarbazole （AEC） by High-Performance Liquid chromatography

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Chinese Journal of Chemistry 2007年第10期25卷 1522-1528页

作者：张英黄琳娟王仲孚 Key laboratory of Resource Biology and Biotechnology in Western China Ministry of Education Xi'an Shaanxi 710069 China Shaanxi Provincial Key laboratory of Biotechnology Xi'an Shaanxi 710069 China Life Science College Northwest University Xi'an Shaanxi 710069 China

3-Amino-9-ethylcarbazole （AEC） was employed for monosaccharide derivatization. The derivatives can be analyzed by high-performance liquid chromatography （HPLC） with an ultraviolet detection （wavelength： 254 nm）. Monosaccharides were quantitatively derivatized with 3-amino-9-ethylcarbazole （AEC） at 70 ℃ for 60 min. The method was linear for all samples over the concentration range tested （r〉0.999）, the precision was found to be satisfactory （R.S.D. 〈 3%）, and the recovery ratios were 〉98.62%. The stability analysis showed R.S.D. was between 1.81%-3.16%. Detection limits for the samples （D-glucose, L-xylose, D-mannose, L-arabinose, and L-rhamnose） ranged from 0.06 to 1.97 ng/mL （S/N=3）. Under the optimized derivatization and HPLC conditions, five monosaccharides were well separated using a narrow bore C18 column （250 mm×4.6 mm） with 0.1 mol/L ammonium acetate containing 25% acetonitrile at a flow rate of 0.5 mL/min. As an application, the method has been successfully applied to the determination of monosaccharide compositions of three polysaccharides SPPA-1, SPPB-1 and SPPC- 1 of Spirulina platensis. This method also has potential application to oligosaccharide or glycan analyses.

关键词： 3-amino-9-ethylcarbazole HPLC monosaccharide derivatization MALDI-TOF

Laying hen performance,egg quality improved and yolk 5-methyltetrahydrofolate content increased by dietary supplementation of folic acid

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Animal Nutrition 2019年第2期5卷 130-133页

作者： Sattar Bagheri Hossein Janmohammadi Ramin Maleki Alireza Ostadrahimi Ruhollah Kianfar Department of Animal Science Faculty of AgricultureUniversity of TabrizTabriz***Iran Department of chromatography Iranian Academic Center for EducationCulture and Researcha(ACECR)UrmiaIran Nutrition Research Center Tabriz University of Medical SciencesTabriz***Iran

This study was performed to evaluate the effect of folic acid(FA) on performance, egg quality and yolk5-methyltetrahydrofolate(5-MTHF) content. A total of 384 Hy-line W36 strain hens from 52 to 58 weeks of age were randomly assigned to 4 groups, and each group received one of following dietary treatments:0, 5.10 and 15 mg FA/kg diet. A completely randomized design was used. Egg production percentage, egg mass and egg weight were increased significantly(P < 0.05) and feed conversion ratio(FCR) was reduced significantly(P < 0.05) by increasing FA content in diets. No significant differences were detected among treatments on egg quality except for shell thickness. The dietary supplementations of laying hens diets with FA significantly increased yolk 5-MTHF content(P = 0.02). Overall, these data demonstrate that dietary supplementation with FA raised 5-MTHF content of yolk and productivity of egg production in laying hens.

关键词： Folic acid 5-Methyltetrahydrofolate Laying hens Yolk Egg

Rapid analysis of fifteen sulfonamide residues in pork and fish samples by automated on-line solid phase extraction coupled to liquid chromatography–tandem mass spectrometry

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Food Science and Human Wellness 2020年第4期9卷 363-369页

作者： Junmei Ma Sufang Fan Lei Sun Liangna He Yan Zhang Qiang Li Hebei Key laboratory of Forensic Medicine College of Forensic MedicineHebei Medical UniversityShijiazhuang 050017China Hebei Food Safety Key laboratory Hebei Food Inspection and Research InstituteShijiazhuang 050227China

The aim of this work was to develop an automated on-line solid phase extraction(SPE)with liquid chromatography-tandem mass spectrometry method for the detection of fifteen sulfonamides in pork and fish *** were extracted with 0.2%formic acid acetonitrile solution,purified by on-line SPE device with HLB column,then separated by XBridge C18 column,using 0.1%formic acid solution and acetonitrile as the mobile *** spectrometric data was acquired under multiple reaction monitoring(MRM)mode using positive ionization *** standard method was used in the quantification,good linear relationship was got in range of 0.1–100 ng/mL and correlation coefficient was higher than *** limits of detection were in the range of 0.125–2.00g/kg and the limits of quantitation were in the range of 0.250–5.00g/*** of the method were in range of 78.3%–99.3%,relative standard deviation were lower than 10%.The method was simple,sensitivity,and could be used for routine supervision and analysis of fifteen sulfonamides in pork and fish.

关键词： Liquid chromatography–tandem mass spectrometry On-line solid phase extraction Sulfonamides Internal standard quantification

Detection of Total Phenols, Essential and Toxic Elements in Latvian Whole Grain Bread

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Journal of Chemistry and Chemical Engineering 2012年第1期6卷 1-6页

作者： Natalia Bobere Anton Podjava Ida Jakobsone Food Chemistry Centre Department of Chemistry University of Latvia Riga L V- 1013 Latvia laboratory of chromatography and Massspectrometry Department of Chemistry University of Latvia Riga L V-1013 Latvia

A survey was carried out with the aim of assessing the level of the total phenolic compounds （TPC）, essential （Na, K, Ca, Mg, Cu, Zn） and toxic （Cd and Pb） elements in 10 Latvian whole grain rye and/or wheat flour bread samples, obtained from the local market. The quantities of the TPC were determined by spectrophotometry. Mineral content was determined by flame photometry, flame atom absorption spectrometry （FAAS） and electrothermal atomic absorption spectrometry （ETAA） after wet digestion in concentrated HNO3. The values were comparable to the literature data. The average content in all the samples was （on a basis of weight of the product） 547 ± 28 mg/100 g for Na; 280 ±20 mg/100 g for K; 32 ± 2 mg/100 g for Ca; 88 ±5 mg/100 g for Mg; 0.49 ± 0.09 mg/100 g for Cu; 1.6 ±0.2 mg/100 g for Zn. Both Pb and Cd were determined below the limit of detection （LOD 5 0.10 mg/100 g）. The LOD values were determined for each element. The TPC content in defatted samples was slightly lower than the non-defatted ones, showing the dependence on the sample preparation. The calculated average levels of the elements were compared with the maximum levels recommended or regulated by the national legislation.

关键词： Essential and toxic elements whole grain bread flame photometry FAAS ETAA total phenols spectrophotometry.

Simultaneous Quantification of Five Stereoisomeric Hexoses in Nine Biological Matrices Using Ultrahigh Performance Liquid chromatography with Tandem Mass Spectrometry

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Journal of Analysis and Testing 2020年第4期4卷 249-256页

作者： Jiali Zuo Runxian Cai Yanpeng An Huiru Tang State Key laboratory of Genetic Engineering Metabonomics and Systems Biology Laboratory At Shanghai International Centre for Molecular PhenomicsZhongshan Hospital and School of Life SciencesHuman Phenome InstituteFudan UniversityShanghai 200438China

Stereoisomeric hexoses are present in almost all biological organisms in the forms of aldoses and ketoses,with diverse physi-ological and pathophysiological *** and simultaneous quantification is vital for understanding their functions ***,such analysis remains challenging owing to their highly similar behavior in chromatography and mass *** combining the pre-column 3-nitrophenylhydrazine derivatization and ultrahigh performance liquid chroma-tography tandem mass spectrometry(UHPLC-MS/MS),here,we developed a method for simultaneous quantification of five important stereoisomeric hexoses including D-glucose,D-galactose,D-mannose,D-fructose and L-sorbose representing both aldoses and *** method achieved baseline-separation for all these five derivatized hexoses chromatographically and had high sensitivity(LOD,femtomole on column),excellent linearity(R2>0.995)and efficiency with stable-isotope *** this method,we further quantified these hexoses in nine biological matrices including human biofluids(serum,urine and saliva),human cells,human and mouse feces,rat liver tissue,mung-bean seeds and peach *** results provided quantitative data for these hexoses in multiple biological samples and showed significant concentration diversity for these hexoses in different biological samples,which demonstrated the applicability of the method for simultaneous quantification of these hexose phenotypes of biological systems.

关键词： Hexose Simultaneous quantification Biological matrices 3-nitrophenylhydrazine Ultrahigh performance liquid chromatography-tandem mass spectrometry