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Journal of Separation Science

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https://www.readbyqxmd.com/read/28106344/fast-separation-of-flavonoids-by-supercritical-fluid-chromatography-using-a-column-packed-with-a-sub-2%C3%A2-%C3%AE-m-particle-stationary-phase
#1
Bo Wang, Xiao-Hua Liu, Wei Zhou, Yan Hong, Shi-Lan Feng
The purpose of this study was to compare the effects of different chromatographic columns for the separation of seven flavonoids. Four different stationary phases are available, including BEH, BEH 2-EP, CSH fluorophenyl and HSS C18 SB. The analytes included calycosin, genistein, medicarpin, calycosin-7-O-β-d-glucoside, formononetin, formononetin-7-O-β-d-glucoside and liquiritigenin. The CSH fluorophenyl column was determined to be the most suitable and provided the fastest separation within 17 min using gradient elution with carbon dioxide as the mobile phase and methanol as the co-solvent...
January 20, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28106341/photocontrolled-extraction-of-uric-acid-from-biological-samples-based-on-photoresponsive-surface-molecularly-imprinted-polymer-microspheres
#2
Cheng-Bin Gong, Zai-Yong Li, Lan-Tao Liu, Yu-Bu Wei, Xia Yang, Cheuk-Fai Chow, Qian Tang
We aim to develop novel photoresponsive surface molecularly imprinted polymer microspheres, a SiO2 -surface molecularly imprinted polymer, for the photocontrolled extraction of uric acid from biological samples. The SiO2 -surface molecularly imprinted polymer was prepared on silica microspheres by surface polymerization and characterized by using scanning electron microscopy, transmission electron microscopy, FTIR spectroscopy, thermogravimetric analysis, nitrogen adsorption-desorption analysis, and UV-visible spectroscopy...
January 20, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28106340/gas-chromatography-with-mass-spectrometry-for-the-determination-of-phthalates-preconcentrated-by-microextraction-based-on-an-ionic-liquid
#3
Juan Ignacio Cacho, Natalia Campillo, Pilar Viñas, Manuel Hernández-Córdoba
A new procedure is proposed for the analysis of migration test solutions obtained from plastic bottles used in the packaging of edible oils. Ultrasound assisted emulsification microextraction with ionic liquids was applied for the preconcentration of six phthalate esters: dimethyl-, diethyl-, di-n-butyl, n-butylbenzyl, di-2-ethylhexyl and di-n-octylphthalate. The enriched ionic liquid was directly analyzed by gas chromatography and mass spectrometry using direct insert microvial thermal desorption. The different factors affecting the microextraction efficiency, like volume of the extracting phase (30 μL of the ionic liquid) and ultrasounds application time (25 s); and the thermal desorption step, such as desorption temperature and time, and gas flow rate, were studied...
January 20, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28106339/determination-of-19-sulfonamides-residues-in-pork-samples-by-combining-quechers-with-dispersive-liquid-liquid-microextraction-followed-by-uhplc-ms-ms
#4
Xiaojing Li, Hong Yu, Rongfei Peng, Pingsheng Gan
A new simple and rapid pretreatment method for simultaneous determination of 19 sulfonamides in pork samples was developed through combining the QuEChERS method with dispersive liquid-liquid microextraction followed by ultra high performance liquid chromatography with tandem mass spectrometry. The sample preparation involves extraction/partitioning with QuEChERS method followed by dispersive liquid-liquid microextraction using tetrachloroethane as extractive solvent and the acetonitrile extract as dispersive solvent which obtained by QuEChERS...
January 20, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28106336/quantitative-analysis-combined-with-chromatographic-fingerprint-and-antioxidant-activities-for-the-comprehensive-evaluation-of-compound-danshen-tablets
#5
Jiao Chen, Jiayue Gao, Guoxiang Sun
The composition of traditional Chinese medicine is extremely complex, so it is difficult to ensure quality consistency. We took Compound Danshen Tablets as the object of the study, by using high-performance liquid chromatography to establish multi-wavelength fusion fingerprints. Characteristic fingerprints of 30 batches of samples were generated at four wavelengths and evaluated by systematic quantified fingerprint method. An on-line antioxidant determination method was used for the determination of the antioxidant components in Compound Danshen Tablets...
January 20, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28106334/rapid-determination-of-the-critical-micelle-concentration-by-taylor-dispersion-analysis-in-capillaries-using-both-direct-and-indirect-detection
#6
Jan Petr
The critical micelle concentration belongs is a basic characteristic of surfactants. In this paper, the process of formation of micelles is studied by Taylor dispersion analysis using capillary electrophoresis instrumentation as a substituent of capillary liquid chromatography. New methods for determination of critical micelle concentration are presented. Sodium octylbenzene sulfonate and sodium dodecylsulfate are used as model compounds with and without chromophore. Two novel approaches based on indirect UV detection and indirect Taylor dispersion analysis with direct UV detection are introduced for the determination of critical micelle concentration value of surfactant without any chromophore...
January 20, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28106330/separation-and-purification-of-two-taxanes-and-one-xylosyl-containing-taxane-from-taxus-wallichiana-zucc-a-comparison-between-high-speed-counter-current-chromatography-and-reversed-phase-flash-chromatography
#7
Junfei Tao, Rongwei Yan, Leilei Zhao, Dongmei Wang, Xinjun Xu
10-Deacetylbaccatin III, an important semi-synthetic precursor of paclitaxel and docetaxel, can be extracted from Taxus wallichiana Zucc.. A process for the isolation and purification of 10-deacetylbaccatin III (1), baccatin III (2) and 7β-xylosyl-10-deacetyltaxol (3) from the leaves and branches of Taxus wallichiana Zucc. via macroporous resin column chromatography combined with high-speed counter-current chromatography or reversed-phase flash chromatography was developed in this study. After fractionation by macroporous resin column chromatography, 80% methanol fraction was selected based on high-performance liquid chromatography and liquid chromatography with mass spectrometry qualitative analysis...
January 20, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28106329/multi-layered-particle-packed-column-evaluation-and-comparison-with-monolithic-and-core-shell-particle-columns-for-the-determination-of-red-azo-dyes-in-sequential-injection-chromatography
#8
Petr Chocholouš, Renato Gil, Carolina C Acebal, Viktor Kubala, Dalibor Šatínský, Petr Solich
A recently presented new type of "multi-layered" organic-inorganic hybrid silica particle packed column YMC-Triart C18 (50 mm × 4.6 mm, 5 μm) was used for the development of a sequential injection chromatography method for determination of five azo dyes (Sudan I, Sudan II, Sudan III, Sudan orange G and para red) in selected food seasonings. The use of a novel sorbent brings attractive features, reduced backpressure, and broader chemical stability together with high separation performance, which are discussed and compared with that of three types of columns typically used in medium-pressure flow chromatography techniques (classic monolithic, narrow monolithic and core-shell particle columns)...
January 20, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28106327/evaluation-of-the-matrix-like-effect-in-multiresidue-pesticide-analysis-by-gas-chromatography-with-tandem-mass-spectrometry
#9
Kazuhiko Akutsu, Masato Yoshimitsu, Yoko Kitagawa, Satoshi Takatori, Naoki Fukui, Masakazu Osakada, Satoko Yamaguchi, Keiji Kajimura, Hirotaka Obana, Takaho Watanabe
In multiresidue pesticide analysis using gas chromatography, it has long been recognized that an increase in the number of pesticides present in a standard solution can result in an enhancement of the peak responses of certain pesticides. Despite being widely acknowledged, this phenomenon has been rarely studied and is poorly understood. In this study, the authors have tentatively called this phenomenon the "matrix-like effect" and demonstrated it clearly using gas chromatography with tandem mass spectrometry...
January 20, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28106326/new-oil-in-salt-liquid-phase-microextraction-on-permutite-for-the-extraction-and-concentration-of-alkaloids-in-coptis-chinensis
#10
Ping Gao, Xuan Chen, Shuang Hu, Xiaohong Bai, Miaomiao Luo
A novel oil-in-salt liquid-phase microextraction was developed and introduced for the extraction and concentration of the trace levels of active alkaloids in Coptis chinensis before analysis by high-performance liquid chromatography with UV detection. Also, the oil-in-salt extraction mechanism was analyzed, the enrichment factor and extraction recovery were redefined, and the proposed method was compared with other methods. In the approach, the mixed solvent of pentanol/octanol (6:4, v/v) and NaCl (20% w/v) are immobilized on the permutite surface in turn to form oil-in-salt double membranes, through which the target analytes can be molecularized though the salting-out effect and for extraction by an organic solvent...
January 20, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28098424/application-of-zein-modified-magnetite-nanoparticles-in-dispersive-magnetic-micro-solid-phase-extraction-of-synthetic-food-dyes-in-foodstuffs
#11
Azam Jangju, Khalil Farhadi, Mehdi Hatami, Samireh Amani, Farzan Esmali, Aisan Moshkabadi, Fatemeh Hajilari
A simple method for the simultaneous and trace analysis of four synthetic food azo dyes including carmoisine, ponceau 4R, sunset yellow and allura red from some foodstuff samples was developed by combining dispersive μ-solid-phase extraction and high-performance liquid chromatography with diode array detection. Zein-modified magnetic Fe3 O4 nanoparticles were prepared and used for μ-solid-phase extraction of trace amounts of mentioned food dyes. The prepared modified magnetic nanoparticles were characterized by scanning electron microscopy and FTIR spectroscopy...
January 18, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28098420/deciphering-chemical-interactions-between-glycyrrhizae-radix-and-coptidis-rhizoma-by-liquid-chromatography-with-transformed-multiple-reaction-monitoring-mass-spectrometry
#12
Zhenhao Li, Ting Liu, Jie Liao, Ni Ai, Xiaohui Fan, Yiyu Cheng
In this study, we propose an integrated strategy for the efficient identification and quantification of herbal constituents using liquid chromatography with mass spectrometry. First, liquid chromatography with quadrupole time-of-flight mass spectrometry was employed for the chemical profiling of herbs, where a targeted following non-targeted approach was developed to detect trace constituents by using structural correlations and extracted ion chromatograms. Next, ion pairs and parameters of MS(2) of quadrupole time-of-flight mass spectrometry were selected to design multiple reaction monitoring transitions for the identified compounds on liquid chromatography with triple quadrupole mass spectrometry...
January 18, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28098419/determination-of-a-broad-spectrum-of-endocrine-disrupting-pesticides-in-fish-samples-by-uhplc-ms-ms-using-the-pass-through-cleanup-approach
#13
Shaoying Liu, Xihui Huang, Quan Jin, Guonian Zhu
We describe a new methodology for the simultaneous determination of the endocrine-disrupting herbicides (acetochlor, alachlor, amitrole and atrazine), fungicides (carbendazim, triadimefon, penconazole and propiconazole) and insecticides (carbaryl and carbofuran) in fish samples followed by high-performance liquid chromatography with tandem mass spectrometry. Samples were extracted and purified using the pass-through cleanup approach. The recoveries of the pesticides were in the range 71.8-116.5%, with relative standard deviations lower than 15...
January 18, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28098414/integrated-photo-grafted-molecularly-imprinted-polymers-with-a-cellulose-acetate-membrane-for-the-extraction-of-melamine-from-dry-milk-before-hplc-analysis
#14
Behrouz Akbari-Adergani, Gholam-Hossein Sadeghian, Alireza Alimohammadi, Zahra Esfandiari
In this study, a new separation technique based on membrane extraction is described for the determination of melamine in dry milk. The water-compatible cellulose acetate membrane, which is photo-grafted by melamine imprinted nanospheres, was prepared by placing the membrane into the polymerization solution containing methacrylic acid as functional monomer, ethylene glycol dimethacrylate as cross-linker, acetonitrile as porogen and melamine as the template molecule. The characterization of the polymeric membrane was performed by Fourier transmission infrared spectroscopy and scanning electron microscopy...
January 18, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28087893/brompheniramine-as-a-novel-probe-for-indirect-uv-detection-and-its-application-for-the-capillary-electrophoresis-of-adamantane-drugs
#15
Pornpan Prapatpong, Brompoj Prutthiwanasan, Nantana Nuchtavorn, Sawanya Buranaphalin, Leena Suntornsuk
Brompheniramine, an antihistamine drug, was employed as a novel UV probe for capillary electrophoresis with indirect UV detection of adamantane drugs (memantine, amantadine, and rimantadine). The probe possesses high molar absorptivity of 24 × 10(3) L/mol cm at 6 mM, which enables the measurement of these non-chromophore analytes without derivatization. The simple background electrolyte (10 mM sodium dihydrogen phosphate (pH 5.0) containing 5 mM brompheniramine and 6 mM β-cyclodextrin) provided the separation of the analytes in a short time (7...
January 14, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28059486/comparison-of-the-origin-and-phenolic-contents-of-lycium-ruthenicum-murr-by-high-performance-liquid-chromatography-fingerprinting-combined-with-quadrupole-time-of-flight-mass-spectrometry-and-chemometrics
#16
Irma Belinda Yossa Nzeuwa, Yuanyuan Xia, Zhou Qiao, Feng Feng, Wenyuan Liu, Wei Qu
The fruits of Lycium ruthenicum Murr. have long been used in folk medicine. Nevertheless, detailed information related to its phenolic composition and its quality control remains scarce. In this study, a simple and reproducible method, based on high-performance liquid chromatography combined with chemometrics, was developed to authenticate 18 samples of L. ruthenicum Murr. collected from different parts of China through fingerprint analysis. The main peaks were identified by quadrupole time-of-flight electrospray ionization mass spectrometry...
January 6, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28059481/zinc-sulfide-nanosheets-as-a-novel-solid-phase-extraction-material-for-flavonoids
#17
Licheng Wang, Wei Fan, Shuman Li, Yong Jia, Xiudan Hou, Xusheng Wang, Shuai Wang, Yong Guo
As a novel solid-phase extraction material, zinc sulfide nanosheets were prepared by a simple method and were used to extract flavonoids. We used scanning electron microscopy to show its nanosheet morphology and energy dispersive X-ray spectroscopy and powder X-ray diffraction to confirm its chemical and phase compositions. Coupled to a high-performance liquid chromatography, the zinc sulfide nanosheets were packed into a micro-column and were used to extract four model flavonoids to examine its extraction ability...
January 6, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28058775/new-procedure-for-the-examination-of-the-degradation-of-volatile-organonitrogen-compounds-during-the-treatment-of-industrial-effluents
#18
Grzegorz Boczkaj, Patrycja Makoś, Andre Fernandes, Andrzej Przyjazny
We present a new procedure for the determination of 32 volatile organonitrogen compounds in samples of industrial effluents with a complex matrix. The procedure, based on dispersive liquid-liquid microextraction followed by gas chromatography with nitrogen-phosphorus and mass spectrometric detection, was optimized and validated. Optimization of the extraction included the type of extraction and disperser solvent, disperser solvent volume, pH, salting out effect, extraction and centrifugation time. The procedure based on nitrogen-phosphorus detection was found to be superior, having lower limits of detection (0...
January 6, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28058766/synthesis-of-molecularly-imprinted-polymers-by-atom-transfer-radical-polymerization-for-the-solid-phase-extraction-of-phthalate-esters-in-edible-oil
#19
Ningning Chen, Juan He, Chaojun Wu, Yuanyuan Li, An Suo, Hongliang Wei, Lijun He, Shusheng Zhang
Novel molecularly imprinted polymers of phthalate esters were prepared by atom transfer radical polymerization using methyl methacrylate as functional monomer, cyclohexanone as solvent, cuprous chloride as catalyst, 1-chlorine-1-ethyl benzene as initiator and 2,2-bipyridyl as cross-linker in the mixture of methanol and water (1:1, v/v). The effect of reaction conditions such as monomer ratio and template on the adsorption properties was investigated. The optimum condition was obtained by an orthogonal experiment...
January 6, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28054455/development-and-validation-of-a-liquid-chromatography-with-tandem-mass-spectrometry-method-for-the-determination-of-nitroimidazole-residues-in-beeswax
#20
Kamila Mitrowska, Maja Antczak
In this study a new method for the determination of 12 nitroimidazoles and their hydroxymetabolites (metronidazole, hydroxymetronidazole, dimetridazole, ronidazole, hydroxydimetridazole, ipronidazole, hydroxyipronidazole, carnidazole, ornidazole, secnidazole, ternidazole, tinidazole) in beeswax has been developed and validated. The optimized sample preparation procedure included melting and dilution of beeswax in a mixture of n-hexane and isopropanol followed by extraction with 2% acetic acid. The extracts were purified on strong cation exchange based solid-phase extraction cartridges and evaporated in a vacuum system with vortex motion...
January 5, 2017: Journal of Separation Science
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