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Journal of Separation Science

Bruno Henrique Fumes, Mariane Aissa Andrade, Maraíssa Silva Franco, Fernando Mauro Lanças
The determination of residues and contaminants in complex matrices such as in the case of food, environmental and biological samples requires a combination of several steps to succeed in the aimed goal. At least three independent steps are integrated to provide the best available situation to deal with such matrices: (1) a sample preparation technique is employed to isolate the target compounds from the rest of the matrix; (2) a chromatographic (second) step further "purifies" the isolated compounds from the co-extracted matrix interferences; (3) a spectroscopy-based device acts as chromatographic detector (ideally containing a tandem high-resolution mass analyzer) for the qualitative and quantitative analysis...
October 19, 2016: Journal of Separation Science
Musfiqur Rahman, A M Abd El-Aty, Sung-Woo Kim, Sung Chul Shin, Ho-Chul Shin, Jae-Han Shim
In pesticide residue analysis, relatively low-sensitivity traditional detectors, such as UV, diode array, electron-capture, flame photometric, and nitrogen-phosphorus detectors, have been used following classical sample preparation (liquid-liquid extraction and open glass column cleanup); however, the extraction method is laborious, time-consuming, and requires large volumes of toxic organic solvents. A quick, easy, cheap, effective, rugged, and safe method was introduced in 2003 and coupled with selective and sensitive mass detectors to overcome the aforementioned drawbacks...
October 19, 2016: Journal of Separation Science
Lingyan Tao, Qing Zhang, Yongjiang Wu, Xuesong Liu
In this study, a fast and effective high-performance liquid chromatography method was developed to obtain a fingerprint chromatogram and quantitative analysis simultaneously of four indexes including gallic acid, chlorogenic acid, albiflorin and paeoniflorin of the traditional Chinese medicine Moluodan Concentrated Pill. The method was performed by using a Waters X-bridge C18 reversed phase column on an Agilent 1200S high-performance liquid chromatography system coupled with diode array detection. The mobile phase of the high-performance liquid chromatography method was composed of 20 mmol...
October 19, 2016: Journal of Separation Science
En-Ping Lin, Tai-Chia Chiu, Ming-Mu Hsieh
Dispersive liquid-liquid microextraction was combined with acetonitrile stacking in capillary electrophoresis for the identification of three selective serotonin reuptake inhibitors (citalopram, fluoxetine, and fluvoxamine) in human fluids such as urine and plasma. Parameters that affect the extraction and stacking efficiency, such as the type and volume of the extraction and disperser solvent, extraction time, salt addition for dispersive liquid-liquid microextraction, and sample matrices, pH, and concentration of the separation buffer for stacking, were investigated and optimized...
October 19, 2016: Journal of Separation Science
Jie Huang, Ning Gan, Fangying Lv, Yuting Cao, Changrong Ou, Haiqing Tang
In this work, a facile and environmentally friendly solid-phase microextraction assay based on on-fiber derivatization coupled with gas chromatography and mass spectrometry was developed for determining four nonvolatile index biogenic amines (putrescine, cadaverine, histamine and tyramine) in fish samples. In the assay, the fiber was firstly dipped into a solution with isobutyl chloroformate as derivatization reagent and isooctane as extraction solvent. Thus, a thin organic liquid membrane coating was developed...
October 18, 2016: Journal of Separation Science
Jianmin Cao, Na Sun, Weisong Yu, Xueli Pang, Yingnan Lin, Fanyu Kong, Jun Qiu
A sensitive and robust multiresidue method for the simultaneous analysis of 114 pesticides in tobacco was developed based on solid-phase extraction coupled with gas chromatography and tandem mass spectrometry. In this strategy, tobacco samples were extracted with acetonitrile and cleaned up with a multilayer solid-phase extraction cartridge Cleanert TPT using acetonitrile/toluene (3:1) as the elution solvent. Two internal standards of different polarity were used to meet simultaneous pesticides quantification demands in the tobacco matrix...
October 18, 2016: Journal of Separation Science
Szymon Bocian, Magdalena Skoczylas, Izabela Goryńska, Maria Matyska, Joseph Pesek, Bogusław Buszewski
A series of phenyl-bonded stationary phases with incorporated polar functional groups were subjected into adsorption investigation. Measurement of acetonitrile and methanol adsorption was obtained using the minor disturbance method. It was observed that adsorption of organic solvent strongly depends on the presence of polar functional groups in the bonded phases that influence the hydrophobicity and polarity of the stationary phase surface. Additionally, relative adsorption of acetonitrile and methanol confirms earlier observations, that the presence of amine and amide groups in the stationary phase changes the relative elution strength of organic solvents...
October 18, 2016: Journal of Separation Science
Jing Wang, Meizhu Zheng, Lina Chen, Zhiqiang Liu, Yuchi Zhang, Chun-Ming Liu, Shu Liu
Hydroxyl radicals are the most reactive free radical of human body, a strong contributor to tissue damage. In this study, liquid chromatography coupled to electrospray ionization mass spectrometry was applied to screen and identify hydroxyl radical scavengers from the total flavonoids of Ginkgo biloba leaves, and high-performance counter current chromatography was used to separate and isolate the active compounds. Furthermore, molecular devices was used to determine hydroxyl radical scavenging activities of the obtained hydroxyl radical scavengers and other flavonoids from Ginkgo biloba leaves...
October 18, 2016: Journal of Separation Science
Ilenia Idda, Nadia Spano, Marco Ciulu, Valeria M Nurchi, Angelo Panzanelli, Maria I Pilo, Gavino Sanna
Saccharides are functional constituents of milk. Although d-lactose represents almost the totality of the saccharides in the milk, minor species, like d-glucose, d-galactose, myo-inositol and, as a result of severe thermal treatments, monosaccharides like d-tagatose, are also detectable. Although chromatography has been the main analytical approach used for accomplishing this task, quite surprisingly a validated gas chromatographic method aimed at the simultaneous determination of these compounds is still needed...
October 17, 2016: Journal of Separation Science
Chengcheng Gong, Tao Chen, Huifeng Chen, Shanshan Zhang, Xinzhu Wang, Weiqing Wang, Jing Sun, Yulin Li, Zhixin Liao
In this paper, we report an efficient method by high-speed counter-current chromatography for the first separation of four aromatic acids and two analogues with similar structures and polarities from Clematis akebioides. Firstly, the ethyl acetate extract was treated by silica gel column chromatography to enrich the target compounds. And then the fraction with target compounds were purified by high-speed counter-counter chromatography using a two-phase solvent system consisting of chloroform/acetonitrile/water (10:6:4, v/v)...
October 17, 2016: Journal of Separation Science
Jun-Qin Qiao, Chao Liang, Lan-Chun Wei, Zhao-Ming Cao, Hong-Zhen Lian
The study on nucleic acid retention in ion-pair reversed-phase high-performance liquid chromatography mainly focuses on size-dependence, however, other factors influencing retention behaviors have not been comprehensively clarified up to date. In this present work, the retention behaviors of oligonucleotides and double-stranded DNAs were investigated on silica-based C18 stationary phase by ion-pair reversed-phase high-performance liquid chromatography. It is found that the retention of oligonucleotides was influenced by base composition and base sequence as well as size, and oligonucleotides prone to self-dimerization have weaker retention than those not prone to self-dimerization but with the same base composition...
October 17, 2016: Journal of Separation Science
ShuLing Wang, Hui Xu
An inorganic-organic hybrid nanocomposite (zinc oxide/polypyrrole) that represents a novel kind of coating for in-tube solid-phase microextraction is reported. The composite coating was prepared by a facile electrochemical polymerization strategy on the inner surface of a stainless steel tube. Based on the coating tube, a novel online in-tube solid-phase microextraction with liquid chromatography and mass spectrometry method was developed and applied for the extraction of three monohydroxy polycyclic aromatic hydrocarbons in human urine...
October 17, 2016: Journal of Separation Science
Liu Sifei, Zhang Guangrui, Qiu Ying, Wang Xiaobo, Guo Lihan, Zhao Yanxin, Tong Meng, Wei Lan, Sun Lixin
In this study, we aimed to establish a comprehensive and practical quality evaluation system for Shenmaidihuang pills. A simple and reliable high-performance liquid chromatography coupled with photodiode array detection method was developed both for fingerprint analysis and quantitative determination. In fingerprint analysis, relative retention time and relative peak area were used to identify the common peaks in 18 samples for investigation. 21 peaks were selected as the common peaks to evaluate the similarities of 18 Shenmaidihuang pills samples with different manufacture dates...
October 14, 2016: Journal of Separation Science
Jufang Wu Ludvigsson, Anders Karlsson, Viktor Kjellberg
In the last decade, core-shell particles have gained more and more attention in fast liquid chromatography separations due to their comparable performance with fully porous sub-2 μm particles and their significantly lower back pressure. Core-shell particles are made of a solid core surrounded by a shell of classic fully porous material. To embrace the developed core-shell column market and use these columns in pharmaceutical analytical applications, 17 core-shell C18 columns purchased from various vendors with various dimensions (50 mm x 2...
October 14, 2016: Journal of Separation Science
Bao Qiong Li, Jing Chen, Xue Wang, Min Li Xu, Hong Lin Zhai
The preprocessing of chromatograms such as the alignment of retention time shifts is often a crucial step in the proper data analysis chain. Here, an efficient approach to align shifted chromatographic signals, longest distance shifting, is presented and highlighted. The performance of this novel strategy was demonstrated by using both simulated chromatograms that covered the different kinds of retention time shifts and the real experimental chromatograms of Pudilan Xiaoyan Tablets obtained by high performance liquid chromatography-photodiode array detector...
October 14, 2016: Journal of Separation Science
Xiaodan Zhu, Chunhong Jia, Zuntao Zheng, Xiaoyuan Feng, Yue He, Ercheng Zhao
A rapid, selective and sensitive sample preparation method based on solid-phase extraction combined with dispersive liquid-liquid microextration was developed for the determination of pyrethroid pesticides in wheat and maize samples. Initially, the samples were extracted with acetonitrile and water solution followed phase separation with the salt addition. The following sample preparation involves a solid-phase extraction and dispersive liquid-liquid microextraction step which effectively provide cleanup and enrichment effects...
October 14, 2016: Journal of Separation Science
Huiqin Guo, Jingjing Xiong, Wentian Ma, Minghuo Wu, Liushui Yan, Kexin Li, Yu Liu
Molecularly imprinted polymers were synthesized using mixed tea saponins as a template and acrylamide-β-cyclodextrin as a co-functional monomer for the specific binding and purification of tea saponins from the defatted cake extract of Camellia oleifera. The adsorption properties of the prepared polymers were systematically evaluated including adsorption kinetics, adsorption isotherms and selective recognition characteristics. It showed that the adsorption kinetics followed the pseudo-first-order kinetic model (R(2) = 0...
October 13, 2016: Journal of Separation Science
Senlin Li, Sainan Li, Ying Tang, Chunming Liu, Lina Chen, Yuchi Zhang
Stroke represents the fourth leading cause of death in the USA and the second leading cause of death worldwide. Lactate dehydrogenase inhibitors are widely used in the treatment of ischemic stroke and natural products are considered a promising source of novel lactate dehydrogenase inhibitors. In this study, we used PC12 cells to determine the protective effect of extracts from the herb Belamcanda chinensis following toxic challenge. Using ultrafiltration high-performance liquid chromatography coupled with photo-diode array detection and electrospray ionization mass spectrometry, we screened and identified isoflavonoids from Belamcanda chinensis extracts...
October 13, 2016: Journal of Separation Science
Qizhen Wei, Zhiyu Song, Jing Nie, Hailun Xia, Fujiang Chen, Zuguang Li, Mawrong Lee
A pretreatment method named tablet-effervescence-assisted dissolved carbon flotation was introduced for the determination of four triazole fungicides in environmental water. In this method, the use of effervescent tablet composed of nontoxic sodium carbonate and sodium dihydrogen phosphate could generate CO2 in situ to assist the dispersion of extraction solvent and to accelerate mass transfer of target analytes. In addition, the simple phase separation simply based on the rising of low-density organic solvent from the aqueous phase was applied rather than the application of apparatus, which demonstrated the potential for on-site extraction in the field...
October 13, 2016: Journal of Separation Science
Xi-Ran He, Chun-Guang Li, Xiao-Shu Zhu, Yuan-Qing Li, Mariam Jarouche, Alan Bensoussan, Ping-Ping Li
There is a recognized challenge in analyzing traditional Chinese medicine formulas because of their complex chemical compositions. The application of modern analytical techniques such as high-performance liquid chromatography coupled with a tandem mass spectrometry has improved the characterization of various compounds from traditional Chinese medicine formulas significantly. This study aims to conduct a bibliometric analysis to recognize the overall trend of high-performance liquid chromatography coupled with tandem mass spectrometry approaches in the analysis of traditional Chinese medicine formulas, its significance and possible underlying interactions between individual herbs in these formulas...
October 12, 2016: Journal of Separation Science
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