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Journal of Separation Science

Petra Steppert, Daniel Burgstaller, Miriam Klausberger, Petra Kramberger, Andres Tover, Eva Berger, Katharina Nöbauer, Ebrahim Razzazi-Fazeli, Alois Jungbauer
The downstream processing of enveloped virus-like particles is very challenging because of the biophysical and structural similarity between correctly assembled particles and contaminating vesicular particles present in the feedstock. We used hydroxyl-functionalized polymethacrylate monoliths, providing hydrophobic and electrostatic binding contributions, for the purification of HIV-1 gag virus-like particles. The clarified culture supernatant was conditioned with ammonium sulfate and after membrane filtration, loaded onto a 1 mL monolith...
December 8, 2016: Journal of Separation Science
Xiaobing Pang, Alastair C Lewis, Marvin D Shaw
Stir bar sorptive extraction is a powerful technique for the extraction and analysis of organic compounds in aqueous matrices. Carbonyl compounds are ubiquitous components in rainwater, however, it is a major challenge to accurately identify and sensitively quantify carbonyls from rainwater due to the complex matrix. A stir bar sorptive extraction technique was developed to efficiently extract carbonyls from aqueous samples following chemical derivatisation by O-(2,3,4,5,6-pentafluorobenzyl) hydroxylamine hydrochloride...
December 8, 2016: Journal of Separation Science
Zahra Ghasempour, Mohammad Alizadeh-Khaledabad, Mohammad-Reza Vardast, Mahmoud Rezazad- Bari
Since natural pigments are lost during the processing of beverages like pomegranate juice, carmoisine, as an adulterant, is often added into the pure juice to improve color characteristics. In this study, molecularly imprinted polymers, as adsorbent of carmoisine, were synthesized using acrylamide, methacrylic acid and 4-vinylpyridine as functional monomers and then they were evaluated in terms of separation and detection of carmoisine. Experiments on batch adsorption of carmoisine 10 ppm stock solution revealed a better binding capacity for 4-vinylpyridine based polymer in comparison to methacrylic acid and acrylamide polymers...
December 8, 2016: Journal of Separation Science
Hang Ren, Xinyue Zhang, Zhen Li, Zhaobin Liu, Jinxiang Li
A novel sulfonic acid group containing hydrophilic strong cation-exchange monolith was prepared by in situ coating 5 μm bare silica particles with the copolymers of glycidyl methacrylate and pentaerythritol triacrylate and further sulfonating the prepared polymer matrix with Na2 SO3 inside a 150 μm I.D. capillary. The preparation conditions were investigated and the method was described in detail. The prepared column was characterized by comparing with its counterparts reported previously in terms of matrix morphology, preparation reproducibility, permeability, swelling-shrinking behavior, mechanical stability, hydrophilicity, binding capacity, and column efficiency...
December 8, 2016: Journal of Separation Science
Saeideh Molaei, Abolfazl Saleh, Vanik Ghoulipour, Shahram Seidi
For the first time, the application of polytetrafluoroethylene powder as an extractant phase collector or holder in liquid-phase microextraction has been developed. For this purpose, the analytical performances of two different ways of applying polytetrafluoroethylene powder in microextraction methods including polytetrafluoroethylene physisorption-assisted emulsification microextraction and dispersive liquid-phase microextraction via polytetrafluoroethylene extractant phase holders have been compared for analysis of aliphatic hydrocarbons in aqueous phases...
December 8, 2016: Journal of Separation Science
Xiangyun Zhang, Hong Lu, Jing Liao, Caiming Tang, Guoying Sheng, Ping'an Peng
Two biomarkers, 5,9-dimethyl-6-isopropyl-2-decanone (1) and 4,9,11-trimethyl-6-isopropyl-2-dodecanone (2), were isolated from Chinese Maoming Oil Shale by silica gel column chromatography and preparative gas chromatography. Their structures were elucidated by using spectroscopic techniques. This article is protected by copyright. All rights reserved.
December 7, 2016: Journal of Separation Science
Si Mi, Yuan-Yuan Zhao, René L Jacobs, Jonathan M Curtis
A method was developed that applies hydrophilic interaction liquid chromatography with tandem mass spectrometry in the multiple-reaction monitoring mode to separate and accurately quantify trimethylamine and trimethylamine N-oxide in a single chromatographic run. This was achieved by converting trimethylamine to ethyl betaine, which is less volatile and hence results in greatly improved quantitation. Ethyl betaine also gives a similar response to trimethylamine N-oxide using positive ion electrospray ionization mass spectrometry...
November 28, 2016: Journal of Separation Science
Xiangwei You, Chengcheng Sui, Yiqiang Li, Xiuguo Wang
A rapid, reliable and sensitive method is reported for the simultaneous analysis of pyrifluquinazon and its main metabolite NNI-0101-1H in fruits (strawberry and cherry) and vegetables (cucumber and tomato) using high-performance liquid chromatography coupled with tandem mass spectrometry. A modified quick, easy, cheap, effective, rugged and safe procedure was used for the sample pre-preparation. The target analytes were extracted with acetonitrile and then cleaned up using dispersive solid phase extraction procedure with primary secondary amine...
November 28, 2016: Journal of Separation Science
Guizhen Li, Tao Zhu, Kyung Ho Row
Deep eutectic solvents were used in both dispersive liquid-liquid microextraction and solid-phase extraction for the purification of chloromycetin and thiamphenicol from milk. In the dispersive liquid-liquid microextraction procedure, deep eutectic solvents mixed with chloroform at different ratios (0:1-5:1, v/v) were used as the extraction agent to optimize the procedure, and the ratio of 2:1 v/v was found to be the best extraction agent with 87.23 and 83.17% recoveries of chloromycetin and thiamphenicol, respectively...
November 26, 2016: Journal of Separation Science
Zirui Zhang, Meng Mei, Yanmei Huang, Xiaojia Huang, Hanyue Huang, Yuxin Ding
A new multiple monolithic fiber solid-phase microextraction using a polydopamine-based monolith as the extraction medium is proposed. The monolith was synthesized by facile in situ copolymerization of N-methacryldopamine and dual cross-linkers (divinylbenzene/ethylenedimethacrylate) in the presence of N,N-dimethylformamide. The effect of the contents of N-methacryldopamine and porogen in the polymerization mixture on the extraction performance was investigated thoroughly. A series of characterization studies was performed to validate the structure and properties of the monolith...
November 26, 2016: Journal of Separation Science
Zuzana Nováková, Vladimír Pejchal, Jan Fischer, Petr Česla
A method for the separation of enantiomers of leucine and phenylalanine benzothiazole derivatives as potential antimicrobial agents was developed using capillary zone electrophoresis with a dual cyclodextrin system. The best resolution of enantiomers was achieved in 100 mmol.L(-1) phosphate background electrolyte pH 3.5 with dual cyclodextrin system consisting of 10 mmol.L(-1) of β-cyclodextrin with 10 mmol.L(-1) of 2-hydroxypropyl-β-cyclodextrin for leucine derivative and 10 mmol.L(-1) of 2-hydroxypropyl-γ-cyclodextrin for phenylalanine derivative, respectively...
November 26, 2016: Journal of Separation Science
Mir Ali Farajzadeh, Elahe Behboudi Khiavi, Parisa Khorram, Mohammad Reza Afshar Mogaddam
In the present study a simple and rapid method for the extraction and preconcentration of some polycyclic aromatic hydrocarbons in water samples has been developed. In this method two sample preparation methods were combined to obtain high extraction recoveries and enrichment factors for sensitive analysis of the selected analytes. In the first stage of the method, a homogeneous solution containing an aqueous solution and cyclohexyl amine is broken by addition of a salt. After centrifugation, the upper collected phase containing the extracted analytes is subjected to the following dispersive liquid-liquid microextraction method...
November 25, 2016: Journal of Separation Science
Jing Sun, Xian-En Zhao, Jun Dang, Xiaoyan Sun, Longfang Zheng, Jinmao You, Xiao Wang
In this work, a hyphenated technique of dual ultrasound-assisted dispersive liquid-liquid microextraction combined with microwave-assisted derivatization followed by ultra high performance liquid chromatography tandem mass spectrometry has been developed for the determination of phytosterols in functional foods and medicinal herbs. Multiple reaction monitoring mode was used for the tandem mass spectrometry detection. A mass-spectrometry-sensitive reagent, 4'-carboxy-substituted rosamine, has been used as the derivatization reagent for five phytosterols, and internal standard diosgenin was used for the first time...
November 25, 2016: Journal of Separation Science
Petr Česla, Jana Křenková
Two-dimensional liquid-phase separations have gained increasing attention for its ability to separate complex sample mixtures. Among the experimental setups used, on-line approach is preferred for reduction of the probability of sample contamination, for easier automation and high-sample throughput. The interfacing of the separation techniques in the on-line mode brings additional demands on proper optimization of the two-dimensional system. In this review, the possibilities of the on-line coupling of liquid chromatography and liquid chromatography with capillary electrophoresis in two-dimensional systems are discussed...
November 25, 2016: Journal of Separation Science
Jian Li, Tian Chen, Yuwei Wang, Zhixiong Shi, Xianqing Zhou, Zhiwei Sun, Dejun Wang, Yongning Wu
Two simplified sample preparation procedures for simultaneous extraction and clean-up of tetrabromobisphenol A, α-, β- and γ-hexabromocyclododecane and polybrominated diphenyl ethers in human serum were developed and validated. The first procedure was based on solid-phase extraction. Sample extraction, purification and lipid removal were carried out directly on an Oasis HLB cartridge. The second procedure was a quick, easy, cheap, effective, rugged and safe based approach using octadecyl-modified silica particles as a sorbent...
November 25, 2016: Journal of Separation Science
Zerong Long, Weiwei Xu, Yumei Peng, Yi Lu, Qian Luo, Hongdeng Qiu
A simple one-pot approach based on molecularly imprinted polymer shells dispersed on the surface of silica for simultaneous determination of rhodamine B and dibenzyl phthalate has been developed. Highly dense molecularly imprinted polymer shells were formed in the mixture of acetonitrile and toluene by the copolymerization of methacrylic acid and ethylene glycol dimethacrylate, as well as two templates, rhodamine B and dibenzyl phthalate, at the directing by the vinyl end groups functional monolayer at surface silica microspheres after 3-methacryloxypropyl trimethoxysilane modification...
November 24, 2016: Journal of Separation Science
Liangfei Ouyang, Qian Liu, Heng Liang
A common drawback of paper-based separation devices is their poor detection limit. In this study, we combined field-amplified sample stacking with moving reaction boundary electrophoresis on a paper chip with six array channels for the parallel separation and concentration of multiple samples. With a new hyphenated technique, the brown I2 from the Fe(3+) -I(-) oxidation-reduction reaction emerged near the boundary between the dilute ethylene diamine tetraacetic acid and potassium iodide and highly concentrated KCl solutions...
November 23, 2016: Journal of Separation Science
Jinhai Huo, Xiaowei Du, Guodong Sun, Yanli Meng, Weiming Wang
The processing of Juglans mandshurica maxim. is important to reduce its toxicity and enhance its efficacy. Simple, efficient, and sensitive ultra high performance liquid chromatography coupled with a time-of-flight mass spectrometry-based chemical profiling approach was proposed to rapidly evaluate the chemical difference between fresh and dry samples. Under the optimised ultra high performance liquid chromatography and quadrupole time-of-flight tandem mass spectrometry conditions, 81 significantly different compounds were rapidly discovered using principal component analysis, and then tentatively identified by comparison with reference substances or inferred through mass spectral fragment ion analysis and literature data...
November 23, 2016: Journal of Separation Science
Chang Liu, Aihua Zhang, Guang-Li Yan, Hui Shi, Hui Sun, Ying Han, Ying Zhou, Xijun Wang
Radix polygalae, the dried roots of Polygala tenuifolia and P. sibirica, is one of the most well-known traditional Chinese medicinal plants. It is an important medicinal plant that has been used as a sedative and to improve memory for a number of years in most of Asia. However, the in vivo constituents of the multiple constituents from Radix Polygalae remain unknown. In the current study, ultra high performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry and the MarkerLynx(TM) software combined with multiple data processing approach were used to study the constituents in vitro and in vivo...
November 22, 2016: Journal of Separation Science
Mengwei Ye, Lijing Zhang, Panpan Xu, Runtao Zhang, Jilin Xu, Xiaokai Wu, Juanjuan Chen, Chengxu Zhou, Xiaojun Yan
A method using high-performance liquid chromatography coupled with tandem mass spectrometry was developed for simultaneous determination of organic acids in microalgae. o-Benzylhydroxylamine was used to derivatize the analytes, and stable isotope-labeled compounds were used as internal standards for precise quantification. The proposed method was evaluated in terms of linearity, recovery, matrix effect, sensitivity, and precision. Linear calibration curves with correlation coefficients of >0.99 were obtained over the concentration range of 0...
November 22, 2016: Journal of Separation Science
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