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Journal of Separation Science

Zehua Li, Haiyang Gao, Jiangying Li, Yajun Zhang
Shaoyao-Gancao decoction, a Chinese herbal formula, is composed of Paeoniae Radix alba and Glycyrrhiza Radix et rhizoma. It has been widely used to treat muscle spasms and asthma. However, little is known about the bioactive components of Shaoyao-Gancao decoction. In the present study, the bioactive compounds in water-extract of Shaoyao-Gancao decoction were separated by the immobilized β2 -adrenoceptor affinity column and identified using quadrupole time-of-flight mass spectrometry. The affinity constants of the separated compounds that bound to β2 -adrenoceptor were determined by frontal analysis...
April 22, 2017: Journal of Separation Science
Jiří Šalplachta, Marie Horká, Karel Šlais
An improved preparative method based on isoelectric focusing of analytes in a cellulose-based separation medium is described in this study. Cellulose is suspended in an aqueous solution of simple buffers, ethylene glycol, glycerol, nonionic surfactant, and colored pI markers. Water partially evaporates during focusing run and the separation takes place in an in-situ generated layer of cellulose, which has a gel-like appearance at the end of analysis. Final positions of analytes are indicated by the positions of zones of focused pI markers...
April 22, 2017: Journal of Separation Science
Qiang Wang, Junnan Xu, Xiang Li, Dawei Zhang, Yong Han, Xu Zhang
Radix Sophorae flavescentis is generally used for the treatments of different stages of prostate cancer in China. It has ideal effects when combined with surgical treatment and chemotherapy. However, its active components are still ambiguous. We devised a comprehensive two-dimensional PC-3 prostate cancer cell membrane chromatography system for screening anti-prostate cancer components in Radix Sophorae flavescentis. Gefitinib and dexamethasone were chosen as positive and negative drugs respectively for validation and optimization the selectivity and suitability of the comprehensive two-dimensional chromatographic system...
April 22, 2017: Journal of Separation Science
Xochitli L Osorio Barajas, Maik A Jochmann, Thorsten Hüffer, Beat Schilling, Torsten C Schmidt
In-tube extraction is a full automated enrichment technique, which consists of a stainless-steel needle, packed with sorbent material for the extraction of volatile and semi-volatile compounds. In principle, all particulate sorbents used for enrichment in air or headspace analysis can be used. However, the selection of the sorbents is merely based on empirical considerations rather than on experimental data, which is caused by a lack of knowledge about the relevant physicochemical properties of the sorbent...
April 20, 2017: Journal of Separation Science
Eslam Pourbasheer, Farnaz Qasemi, Maryam Rouhi, Zhila Azari, Mohammad Reza Ganjali
A method was developed for determination of 2-mercaptobenzimidazole in water and urine samples by dispersive liquid-liquid microextraction coupled with ultraviolet-visible spectrophotometry. It was essential to peruse the effect of all parameters that can likely influence the performance of extraction. The influence of parameters on dispersive liquid-liquid microextraction such as dispersive and extraction solvent volume and sample volume were studied. The optimization was carried out by the central composite design method...
April 20, 2017: Journal of Separation Science
Xinquan Wang, Peipei Qi, Xiangyun Wang, Qian Zhang, Zhiwei Wang, Xiahong Xu, Hao Xu, Hu Zhang, Qiang Wang
We aimed to develop an efficient cleanup method for multi-pesticides residue analysis in complex plant matrices, shallot, ginger, garlic, onion, leek and celery. Column chromatography was used as the cleanup method and fabricated with florisil and graphitized carbon black as the adsorbents. The amount of the graphitized carbon black adsorbent and the choice of the elution solvent were systematically investigated for exploring the best combination. The target pesticides covered organochlorine, pyrethroid and organophosphorus pesticides, and were 38 in total...
April 20, 2017: Journal of Separation Science
Hui Zhu, Xiao Liu, Ting Ting Zhu, Xiao Li Wang, Kun Ming Qin, Ke Pei, Bao Chang Cai
Prepared rhubarb, as one of the main processed products of rhubarb, has a good effect on promoting blood circulation. This paper described a rapid, sensitive and selective ultra-fast liquid chromatography with tandem mass spectrometry method for simultaneous quantification of five anthraquinones (rhein, aloe-emodin, chrysophanol, emodin and physcion) and gallic acid in plasma. Chromatographic separation was performed on an Extend C18 column at the temperature of 30°C using the mobile phase consisted of 0.1% aqueous formic acid and acetonitrile...
April 20, 2017: Journal of Separation Science
Jolanta Flieger, Joanna Feder-Kubis, Małgorzata Tatarczak-Michalewska, Anita Płazińska, Anna Madejska, Marta Swatko-Ossor
We present the specific cooperative effect of a semisynthetic glycopeptide antibiotic teicoplanin and chiral ionic liquids containing the (1R,2S,5R)-(-)-menthol moiety on the chiral recognition of enantiomers of mandelic acid, vanilmandelic acid and phenyllactic acid. Experiments were performed chromatographically on an Astec Chirobiotic T chiral stationary phase applying the mobile phase with the addition of the chiral ionic liquids. The stereoselective binding of enantiomers to teicoplanin in presence of new chiral ionic liquids were evaluated applying thermodynamic measurements and the docking simulations...
April 20, 2017: Journal of Separation Science
Xiuqin Wang, Juanjuan Feng, Yanan Bu, Yu Tian, Chuannan Luo, Min Sun
Stainless-steel wires coated with mesoporous titanium oxide were placed into a polyether ether ketone tube for in-tube solid-phase microextraction, and the coating sorbent was characterized by X-ray diffraction and scanning electron microscopy. It was combined with high performance liquid chromatography to build an online system. Using eight polycyclic aromatic hydrocarbons as the analytes, some conditions including sample flow rate, sample volume, organic solvent content and desorption time were investigated...
April 20, 2017: Journal of Separation Science
Qing Wang, Bin Qiu, Xianbo Chen, Bin Wang, Hui Zhang, Xiaoyuan Zhang
A novel mixed hemimicelles and magnetic dispersive solid-phase extraction method based on long-chain ionic liquids for the extraction of five fluorescent whitening agents was established. The factors influenced on extraction efficiency were investigated. Under the optimal conditions, namely, the pH of sample solution at 8.0, the concentration of long chain ionic liquid at 0.5 mmol/L, the amount of Fe3 O4 nanoparticle at 12 mg, extraction time at 10 min, pH 6.0 of methanol as eluent and the desorption time at 1 min, satisfactory results were obtained...
April 12, 2017: Journal of Separation Science
Xiaoxing Liu, Shuyu Xie, Tengteng Ni, Dongmei Chen, Xu Wang, Yuanhu Pan, Yulian Wang, Lingli Huang, Guyue Cheng, Wei Qu, Zhenli Liu, Yanfei Tao, Zonghui Yuan
Carbon nanotubes-magnetic nanoparticles, comprising ferroferric oxide nanoparticles and carbon nanotubes, were prepared through a simple one-step synthesis method and subsequently applied to magnetic solid-phase extraction for the determination of polyether antibiotic and s-triazine drug residues in animal food coupled with liquid chromatography with tandem mass spectrometry. The nanocomposites were characterized by transmission electron microscopy, X-ray diffraction, and vibrating sample magnetometry. The components within the nanocomposites endowed the material with high extraction performance and manipulative convenience...
April 12, 2017: Journal of Separation Science
Georg Kreisberger, Wolfgang W Buchberger
Hindered amine light stabilizers are of essential for the stabilization of synthetic polymers, particularly for materials used for outdoor applications. Although up to now a considerable number of studies dealing with the analytics of this class of stabilizers had been published, especially the determination of oligomeric hindered amine light stabilizers is still an analytical challenge. In the current work a fast and simple liquid chromatographic method for the quantitative determination of oligomeric hindered amine light stabilizers is presented...
April 12, 2017: Journal of Separation Science
Yunliang Zheng, Cong Cao, Meihua Lin, You Zhai, Zhiwei Ge, Jianzhong ShenTu, Lihua Wu, Xingjiang Hu
Physalin D is known to show extensive bioactivities. However, no excretion study has elucidated the excretion of physalin D and its metabolites. This study investigates the excretion of physalin D and its metabolites in rats. Metabolites in rat urine and feces were separated and identified by liquid chromatography with triple quadrupole time-of-flight mass spectrometry. Furthermore, a validated high-performance liquid chromatography with tandem mass spectrometry method was developed to quantify physalin D, physalin D glucuronide, and physalin D sulfate in rats feces and urine after the intragastric administration of physalin D...
April 7, 2017: Journal of Separation Science
Meihua Hu, Pengcheng Huang, Lili Suo, Fangying Wu
A new method based on cetylpyridinium chloride coated ferroferric oxide/silica magnetic microspheres as an efficient solid-phase adsorbent was developed for the extraction and enrichment of ochratoxin A. The determination of ochratoxin A was obtained by high-performance liquid chromatography with fluorescence detection. In the presence of cetylpyridinium chloride, the adsorption capacity of ferroferric oxide/silica microspheres was 5.95 mg/g for ochratoxin A. The experimental parameters were optimized, including the amounts of ferroferric oxide/silica microspheres (20 mg) and cetylpyridinium chloride (0...
April 7, 2017: Journal of Separation Science
Chengtian Huang, He Zhu, Yang Yu, Qi Ding, Fuyan Jia, Bochui Zhao, Siyuan Wei, Dangsheng Gong, Weichang Xu, Mingshan Ji
An easy, effective and sensitive analytical method for the simultaneous determination of a novel fungicide pyrametostrobin and its two metabolites pyrametostrobin-M1 and pyrametostrobin-M2 in cucumber and soil was developed using a quick, easy, cheap, effective, rugged, and safe method with high-performance liquid chromatography and tandem mass spectrometry. The extraction solvent was acetonitrile, and cleanup sorbents were primary secondary amine and graphitized carbon black for cucumber samples and primary secondary amine for soil samples...
April 7, 2017: Journal of Separation Science
Alexis G Huckabee, Charu Yerneni, Rachel E Jacobson, Edwin J Alzate, Tse-Hong Chen, Mary J Wirth
It is difficult to pack chromatographic particles having polymeric bonded phases because solvents used for making a stable slurry cause the polymer layer to swell. Growth of the polymer inside the column (in situ) after packing was investigated and compared with conventional, ex situ polymer growth. The method of activators generated by electron transfer, along with atom-transfer radical polymerization, enabled polymerization under ambient conditions. Nonporous, 0.62 μm silica particles with silane initiators were used...
April 7, 2017: Journal of Separation Science
Yao Wang, Ruiyang Ma, Ruobai Xiao, Qiuhua Wu, Chun Wang, Zhi Wang
In this study, corn stalk was used to synthesize a magnetic adsorbent by pyrolysis together with KHCO3 as the chemical activator and iron(III) salt as the magnetic reagent. The characterization by scanning electron microscopy, transmission electron microscopy and N2 adsorption-desorption analysis showed that the magnetic carbon adsorbent had a structure of hierarchical pores with a high specific surface area. To evaluate its adsorption performance, the adsorbent was used for the extraction of carbamates pesticides (propoxur, isoprocarb and fenobucarb) from water and zucchini samples before high-performance liquid chromatography analysis...
April 6, 2017: Journal of Separation Science
Yu-Hsuan Yeh, Wen-Chi Chen, Sarah Y Chang
A sensitive method for the determination of mexiletine and lidocaine using surfactant-assisted dispersive liquid-liquid microextraction coupled with capillary electrophoresis was developed. Triton x-100 and dichloromethane were used as the dispersive agent and extraction solvent, respectively. After the extraction, mexiletine and lidocaine were analyzed using capillary electrophoresis with UV detection. The detection sensitivity was further enhanced through the use of field-amplified sample stacking. Under optimal extraction and stacking conditions, the calibration curves were linear over a concentration range of 0...
April 5, 2017: Journal of Separation Science
Haojiang Wang, Wenli Hu, Qiong Zheng, Wei Bian, Zian Lin
A novel mercaptotetrazole-silica hybrid monolithic column was prepared for capillary liquid chromatography, in which the thiol-end mercaptotetrazole was mixed with hydrolyzed γ-methacryloxypropyltrimethoxysilane and tetramethyloxysilane for the co-polycondensation and thiol-ene click reaction in a one-pot process. The effects of the molar ratio of silanes, the amount of mercaptotetrazole, and the volume of porogen on the morphology, permeability and pore properties of the as-prepared mercaptotetrazole-silica hybrid monoliths were investigated in detail...
April 4, 2017: Journal of Separation Science
Jingjing Wang, Zhiguo Gong, Tingting Zhang, Shun Feng, Jide Wang, Yi Zhang
As a result of the low water content and high fat matrices in nuts, it is very difficult to simultaneously determine multi-pesticides in trace levels. Here, a sample pretreatment method was developed in which, microwave-assisted solvent extraction was firstly used to extract pesticides, and then a two-step cleanup method was conducted combining freeze-out with dispersive solid-phase extraction to removed lipidic matrix. By this way, it was achieved that 106 pesticides were simultaneously determined in the complicated nut sample by using an ultra high pressure liquid chromatography coupled to a tandem mass spectrometer platform...
April 3, 2017: Journal of Separation Science
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