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Journal of Separation Science

Bao Chen, Zhengbo Liu, Yuwei Zhang, Wei Li, Yanjun Sun, Yufang Wang, Yanhua Wang, Yinshi Sun
Three polyacetylenes were isolated and purified from Platycodon grandiflorum A. DC for the first time by high-speed counter-current chromatography using a two-phase solvent system composed of hexane/ethyl acetate/methanol/water (1:31:1:31, v/v/v/v) and high-performance liquid chromatography with an Agilent ZORBAX(®) SB-C18 column (4.6 mm × 150 mm, 5 μm). After separation by high-speed counter-current chromatography and high-performance liquid chromatography, we obtained 3.5 mg of platetyolin A, 4.1 mg of platetyolin B, and 18...
November 18, 2017: Journal of Separation Science
Bartłomiej Witkowski, Anna Duchnowicz, Monika Ganeczko, Agnieszka Laudy, Tomasz Gierczak, Magdalena Biesaga
Simplified method for simultaneous identification of proteins, drying oils, waxes and resins in the works-of-art samples was developed. Liquid chromatography with mass spectrometry and gas chromatography with mass spectrometry were used to identify natural materials most frequently encountered in historical paintings. Protein binders were extracted with ammonia and purified using miniaturized solid-phase microextraction (Omix tips) to efficiently suppress matrix interferences. Zwitterionic stationary phase was used for separation of sixteen underivatized amino acids analysis with hydrophilic interaction liquid chromatography that were subsequently quantified with liquid chromatography with mass spectrometry...
November 18, 2017: Journal of Separation Science
Maria Kechagia, Victoria Samanidou, Abuzar Kabir, Kenneth G Furton
A highly selective molecularly imprinted polymer sorbent was synthesized and employed for the simultaneous determination of six sulfonamide antibiotic residues (sulfanilamide, sulfacetamide, sulfadiazine, sulfathiazole, sulfamerazine and sulfamethizole) in milk samples. Multi-analyte imprinted particles were used as sorbent in solid phase extraction. Sulfonamides were separated on a high-performance liquid chromatography column (Merck-Lichrospher RP18e, 5 μm 250 × 4 mm) and further identified and quantified by diode array detection...
November 18, 2017: Journal of Separation Science
Zhijuan Wang, Qing Zhang, Haiyu Li, Qing Lv, Wan Wang, Hua Bai
This paper presents a simple, rapid, and green method based on a static headspace gas chromatography with mass spectrometry for determining 58 fragrance allergens in plush toys. This study is the first to meet the requirement for simultaneously determining 66 fragrances, except for eight natural extracts restricted by the European Toy Safety Directive 2009/48/EC. A minimal amount of sample (20 mg) and acetone solvent (20 μL) were placed in a headspace vial. A gas-solid equilibration of fragrances between the headspace and the sample was achieved within 10 min under the vapor atmosphere of acetone at 200°C, which allowed the fragrances in the sample to be measured by gas chromatography with mass spectrometry...
November 17, 2017: Journal of Separation Science
Lucas Morés, Adriana Neves Dias, Eduardo Carasek
In this study, a new method was developed in which a biosorbent material is used as the extractor phase in conjunction with a recently described sample preparation technique called thin-film microextraction and a 96-well plate system. The method was applied to the determination of emerging contaminants, such as 3-(4-methylbenzylidene) camphor, ethylparaben, triclocarban and bisphenol A, in water samples. The separation and detection of the analytes were performed by high-performance liquid chromatography with diode array detection...
November 15, 2017: Journal of Separation Science
Jianwu Wang, Yuanxin Hang, Tingting Yan, Jiahui Liang, Zhiqiang Huang, Huilan Xu
A precise identification method was developed to identify the flavors and fragrances added to tea matrix artificially using gas chromatography with mass spectrometry and gas chromatography with quadrupole time-of-flight mass spectrometry. The proposed method was based on the corresponding "three-column retention indices, two exact mass numbers, one mass spectrum matching degree" database of 40 kinds of common flavors and fragrances. The intra-day and the inter-day relative standard deviation of the retention indices were less than 0...
November 14, 2017: Journal of Separation Science
Florian Meischl, Christian G Kirchler, Michael A Jäger, Christian W Huck, Matthias Rainer
We present a novel method for the quantitative determination of the clean-up efficiency to provide a calculated parameter for peak purity through iterative fitting in conjunction with design of experiments. Rosemary extracts were used and analyzed before and after solid-phase extraction using a self-fabricated mixed-mode sorbent based on poly(N-vinylimidazole/ethylene glycol dimethacrylate). Optimization was performed by variation of washing steps using a full three-level factorial design and response surface methodology...
November 14, 2017: Journal of Separation Science
Xiaolu Yu, Hang Liu, Chengjun Pu, Junhao Chen, Ying Sun, Lin Hu
A modified quick, easy, cheap, effective, rugged and safe method was established for simultaneous extraction and cleanup of multiple antibiotics in leafy vegetables, and ultra high performance liquid chromatography with tandem mass spectrometry was used for analysis. Antibiotics in leafy vegetables were extracted with citric acid/sodium citrate in mixed solvents consisting of acetonitrile/methanol (85:15 v/v) from 10 g of vegetables. Octadecylsilyl and graphitized carbon black were used as dispersant adsorbents...
November 14, 2017: Journal of Separation Science
Zhongping Huang, Yueting Xu, Yilei Huang, Charles Liu, Kezhi Jiang, Lili Wang
A novel method on basis of direct analysis in real time integrated with mass spectrometry was established and applied into rapid determination of ginkgolic acids in Ginkgo biloba kernels and leaves. Instrument parameter settings were optimized to obtain the sensitive and accurate determination of ginkgolic acids. At the sample introduction speed of 0.2 mm/s, high intensity of [M-H](-) ions for ginkgolic acids were observed in the negative ion mode by utilization of high purity helium gas at 450°C. 2 μL methanol extract of Ginkgo biloba kernels or leaves dropped on the surface of Quick-Strip module was analyzed after solvent evaporated to dryness...
November 14, 2017: Journal of Separation Science
Arezou Amiri Pebdani, Shayesteh Dadfarnia, Ali Mohammad Haji Shabani, Saeid Khodadoust, Mohammad Sharif Talebianpoor
A modified dispersive liquid phase microextraction based on sequential injection solidified floating organic drop was developed for simultaneous separation/preconcentration of trace amounts of phenobarbital and phenytoin. The important factors affecting on the extraction recovery including pH, the volume of extraction solvent, ionic strength and the number of injections were investigated and optimized by Box-Behnken design and desirability function. Under the optimum experimental conditions, the calibration graph was linear in the concentration range of 1...
November 13, 2017: Journal of Separation Science
Jingdan Zhang, Xiaoxue Zhang, Yangyang Zhao, Aihua Song, Wei Sun, Ran Yin
In this study, a reliable and sensitive ultra high performance liquid chromatography coupled with Fourier transform ion cyclotron resonance mass spectrometry method was developed for the systematic study of the metabolic profile of Kudiezi injection in rat plasma, bile, urine and feces after intravenous administration of a single dose. The chromatographic separation was performed on an Agilent Eclipse Plus C18 column (4.6 mm × 50 mm, 1.8 μm) and the identification of prototype components and metabolites was achieved on a Bruker Solarix 7...
November 13, 2017: Journal of Separation Science
Sulaiman Krait, Matthias Heuermann, Gerhard K E Scriba
Dextromethorphan is a centrally acting antitussive drug, while its enantiomer levomethorphan is an illicit drug with opioid analgesic effects. As capillary electrophoresis has been proven as an ideal technique for enantiomer analysis, the present study was conducted in order to develop a capillary-electrophoresis-based limit test for levomethorphan. The analytical target profile was defined that the method should be able to determine levomethorphan with acceptable precision and accuracy at the 0.1 % level. From initial scouting experiments, a dual selector system consisting of sulfated β-cyclodextrin and methyl-α-cyclodextrin was identified...
November 13, 2017: Journal of Separation Science
Kai Cai, Zhangmin Xiang, Hongqin Li, Huina Zhao, Yechun Lin, Wenjie Pan, Bo Lei
This work describes a rapid, stable, and accurate method for determining the free amino acids, biogenic amines, and ammonium in tobacco. The target analytes were extracted with microwave-assisted extraction and then derivatized with diethyl ethoxymethylenemalonate, followed by ultra high performance liquid chromatography analysis. The experimental design used to optimize the microwave-assisted extraction conditions showed that the optimal extraction time was 10 min with a temperature of 60°C. The stability of aminoenone derivatives was improved by keeping the pH near 9...
November 13, 2017: Journal of Separation Science
Yongmei Wang, Chongchong Yang, Yan Sun, Fengtao Qiu, Yang Xiang, Guoqi Fu
Surface molecular imprinting over functionalized nanoparticles has proved to be an effective approach for construction of artificial nanomaterials for protein recognition. Herein, we report a strategy for synthesis of core-shell protein-imprinted nanoparticles by the functionalization of nano-cores with ionic liquids followed by aqueous precipitation polymerization to build thermo-responsive imprinted polymer nano-shells. The immobilized ionic liquids can form multiple interactions with the protein template...
November 12, 2017: Journal of Separation Science
Mingrong Qian, Hua Yang, Zuguang Li, Yanping Liu, Jianmei Wang, Huizhen Wu, Xiaofeng Ji, Jie Xu
An analytical method for the simultaneous determination of 13 mycotoxins in feed by magnetic dispersive solid-phase extraction combined with ultra high performance liquid chromatography and tandem mass spectrometry was developed. The samples were extracted with acetonitrile/water (80:20, v/v, containing 3% acetic acid), and separated by centrifugation after salting-out, and then treated with magnetic adsorbents to remove interferences. The separation of target mycotoxins was performed on an ACQUITY UPLC HSS T3 column using a mobile phase consisting of 1 mmol/L ammonium acetate with 0...
November 10, 2017: Journal of Separation Science
Yujuan Hua, Myron Hawryluk, Ronda Gras, Randall Shearer, Jim Luong
A fast and reliable analytical technique for the determination of total sulfur levels in complex hydrocarbon matrices is introduced. The method employed flow injection technique using a gas chromatograph as a sample introduction device and a gas phase dual-plasma sulfur chemiluminescence detector for sulfur quantification. Using the technique described, total sulfur measurement in challenging hydrocarbon matrices can be achieved in less than 10 s with sample-to-sample time of less than 2 min. The high degree of selectivity and sensitivity towards sulfur compounds of the detector offers the ability to measure low sulfur levels with a detection limit in the range of 20 ppb (w/w) S...
November 10, 2017: Journal of Separation Science
Jiapeng Long, Bing Liang, Sanxi Li, Zhenbin Chen
Molecularly imprinted polymers of glycyrrhizic acid were prepared by solution polymerization using glycyrrhizic acid as the template molecule, N-vinypyrrolidone as functional monomer, N,N-methylene bisacrylamide as cross-linker and ascorbic acid and hydrogen peroxide as initiators. Focused on the adsorption capacity and separation degree of the polymer to glycyrrhizic acid, the effects of the monomers, crosslinker and initiators were investigated and optimized. Finally, the structure of the polymer was characterized by using Fourier transform infrared spectroscopy and scanning electron microscopy...
November 10, 2017: Journal of Separation Science
Suresh Pal Anagoni, Asma Kauser, Gopal Maity, Vijayasarathi V R Upadhyayula
Chemical warfare agents such as organophospshorus nerve agents, mustard agents, and psychotomimetic agent like 3-quinuclidinylbenzilate degrade in the environment and form acidic degradation products the analysis of which is difficult under normal analytical conditions. In the present work a simultaneous extraction and derivatization method in which the analytes are butylated followed by gas chromatography and mass spectrometric identification of the analytes from aqueous and soil samples was carried out. The extraction was carried out using ion-pair solid-phase extraction with tetrabutylammonium hydroxide followed by gas chromatography with mass spectrometry in the electron ionization mode...
November 9, 2017: Journal of Separation Science
Zheyuan Qian, Jian Le, Xiujuan Chen, Shengni Li, Hongjie Song, Zhanying Hong
A rapid, sensitive and selective liquid chromatography with tandem mass spectrometry method was developed and fully validated for the simultaneous quantification of arotinolol and amlodipine in rat plasma. Two internal standards were introduced with metoprolol as the internal standard of arotinolol and (S)-amlodipine-d4 as the internal standard of amlodipine. The analytes were isolated from 50.0 μL plasma samples by a simple protein precipitation using acetonitrile. The chromatographic separation was achieved in 5 min on a C18 column...
November 8, 2017: Journal of Separation Science
Rahma Sr Mahrous, Hoda M Fathy, Rasha M Abu El-Khair A, Abdallah A Omar
A sensitive, reliable, simple and rapid thin-layer chromatographic method has been developed for routine analysis of withanolide S content for the purpose of quality control assessment of chemotype III of W. somnifera. The new method was used first to compare the accumulation of withanolide S in different parts of the plant, which was found to be the highest in the leaves extract (0.21% w/w). Secondly to investigate different extraction parameters that improve the extraction efficiency of withanolides from the leaves using conventional and ultrasound-assisted extraction methods...
November 8, 2017: Journal of Separation Science
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