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Journal of Separation Science

Shobhit Misra, M Farooq Wahab, Darshan C Patel, Daniel W Armstrong
Modern chromatographic data acquisition software often behave as black boxes where the researchers have little control over the raw data processing. One of the significant interests of separation scientists is to extract physico-chemical information from chromatographic experiments and peak parameters. In addition, column developers need the total peak shape analysis to characterize the flow profile in chromatographic beds. Statistical moments offer a robust approach for providing detailed information for peaks in terms of area, its center of gravity, variance, resolution, and its skew without assuming any peak model or shape...
February 16, 2019: Journal of Separation Science
Fernando Maya, Brett Paull
This review summarizes recent development made in the incorporation of functional materials into organic polymer monoliths, together with new monolithic forms and formats, which enhance their application as supports and stationary phase materials for sample preparation and chromatographic separations. While polymer monoliths are well known supports for the separation of large molecules, recent development have been made to improve their features for the separation of small molecules. The selectivity and performance of organic polymer monoliths has been improved by the incorporation of different materials, such as metal-organic frameworks, covalent organic frameworks, or other types of nanostructured materials (carbon nanohorns, nanodiamonds, polyoxometalates, layered double hydroxides, or attapulgite)...
February 15, 2019: Journal of Separation Science
Chaoran Liu, Xinya Liu, Philip J Marriott, Heng Qian, Zilin Meng, Zhirong Yang, Runhua Lu, Haixiang Gao, Wenfeng Zhou
In this work, a method for the analysis of benzoylurea insecticides, including hexaflumuron, flufenoxuron, lufenuron and chlorfluazuron, in tea samples by HPLC with Fe3 O4 - hyperbranched polyester nanocomposite as the adsorbent for magnetic solid-phase extraction was developed. The magnetic nanocomposite was prepared and characterized by infrared spectroscopy, vibrating sample magnetometry and scanning electron microscopy. The as-prepared nanocomposite was used as the sorbent for extraction and preconcentration of pesticide residues in tea samples...
February 15, 2019: Journal of Separation Science
Chao Ma, Huida Guan, Zhengcai Ju, Shuping Li, Gang Deng, Yunpeng Zhang, Qiyan Lin, Xuemei Cheng, Li Yang, Zhengtao Wang, Changhong Wang
Notoginsenoside Fc (NGFc), a protopanaxadiol-type saponin, shows multi-pharmacological activities. Chemical stability evaluation plays a crucial role in drug development. In this study, the forced degradation behavior of NGFc was investigated under hydrolytic and oxidative conditions. A specific ultra-high performance liquid chromatography with quadrupole time-of-flight mass spectrometry was developed for the separation, identification, and characterization of the degradation products of NGFc. Fifty potential degradation products were formed via deglycosylation, dehydration, hydration, isomerization, side-chain cleaving, oxidation, and superoxidation...
February 15, 2019: Journal of Separation Science
Irena Choma, Małgorzata Olszowy, Marek Studziński, Sebastian Gnat
The great prevalence of thin-layer chromatography over HPLC is connected with the possibility of analyzing many samples in parallel. Therefore, the method is often used in screening and/or effect directed analysis to compare composition and chemical/biological properties of many samples in one run. It was already proved, that high performance thin-layer chromatography, in many cases, can replace HPLC for quantitative analysis. The main aim of the paper is to show that also simple thin-layer chromatography can be used as a quantitative or at least as a semi-quantitative method, even when it concerns effect directed analysis e...
February 15, 2019: Journal of Separation Science
Roman Papoušek, Stanislav Žák, Pavel Štverka, Aleš Gavenda, Lucie Borovcová, Petr Barták
The masking derivatization was introduced for the determination of residual solvents in samples containing a volatile reactive matrix component(s). Isobutylboronic acid, used in the last step of Bortezomib synthesis, represents such a compound passing to the gas phase and deteriorating a chromatographic column during a headspace analysis. The masking derivatization with 1,8-diaminonaphthalene allowed a simple and straightforward conversion of isobutylboronic acid to a stable nonvolatile derivative and thus prevented GC column deterioration...
February 14, 2019: Journal of Separation Science
Qamar Salamat, Yadollah Yamini, Morteza Moradi, Abolfazl Farahani, Neda Feizi
In the present study, a supramolecular solvent was formed from reverse micelle aggregates of octanol. The proposed supramolecular solvent was used for rapid extraction of some antidepressants drugs including amitriptyline, imipramine, desipramine, maprotiline, sertraline, and doxepin from biological samples. Alkanol-based supramolecular solvent have a unique array of physicochemical properties, making them a very attractive alternative to replace organic solvents in analytical extractions. The parameters affecting the extraction of target analytes (i...
February 13, 2019: Journal of Separation Science
Parezhati Pataer, Turghun Muhammad, Yunusjan Turahun, Wenwu Yang, Sailemayi Aihebaier, Muyasier Wubulikasimu, Lingxin Chen
This paper describes a stoichiometric approach to synthesis molecularly imprinted polymers specific for auramine O. Using the stoichiometric interaction in molecular imprinting no excess of binding sites is necessary and binding sites are only located inside the imprinted cavities. The free base of template was obtained to facilitate the interaction with the monomers. Itaconic acid was selected as functional monomer and stoichiometric ratio of the interaction with the free base was investigated. The molecularly imprinted polymers preparation conditions such as cross-linker, molar ratio, porogen were optimized to be divinylbenzene, 1:2:20 and chloroform/N,N-dimethylformamide, respectively...
February 13, 2019: Journal of Separation Science
Fernanda das Neves Costa, Ricardo Moreira Borges, Gilda Guimarães Leitão, Gerold Jerz
Salicornia species have just been introduced to the European market as a vegetable named 'samphire', 'green asparagus' or 'sea asparagus'. Due to its increasing attention, and associated value, minor compounds of Salicornia gaudichaudiana Moq were investigated. The use of countercurrent chromatography and mass spectrometry enabled the search for known, as well as potentially novel natural products. Their identification was achieved based on molecular weights, and mass-spectrometric fragmentation data. Low detection limits enabled the visualization of all compounds with their identification in almost real time close to the preparative countercurrent chromatography experiment...
February 11, 2019: Journal of Separation Science
Ning Xu, Haifeng Lin, Katsumi Uchiyama, Jin-Ming Lin
Pipes are the primary structural elements used for transporting fluid in various industries. The most common damage mechanism is corrosion, which occurs in pipes surface of turbine. The corrosive compounds for pipes are inorganic ion (Na+ , Cl- , NH4 + , NO3 - , et al.) and grinding oil. For rapid and quantitative detection of inorganic ions on site, the more reliable and reproducible analytical methods are demanded. A highly efficient solid-liquid sampling collection system is introduced in this work. Papering on the sample surface, inorganic cations and anions were simultaneously collected and analyzed by capillary electrophoresis (CE) with indirect ultraviolet detection...
February 11, 2019: Journal of Separation Science
Guanwei Gao, Hongping Chen, Yunfeng Chai, Lili Jin, Xin Liu, Chengyin Lu
Phthalimide can be formed from either degradation of folpet and phosmet, or reaction of phthalic anhydride with primary amino groups. Consequently, the sum of phthalimide and folpet, expressed as folpet-residue definition, is highly prone to false-positive levels of folpet in tea. An analytical method is thus urgently needed to investigate the residue level and source of phthalimide in tea. In this work, we developed an accurate method of determining phthalimide and phthalic acid (the indicator of phthalic anhydride) by acetonitrile extraction and 3-bromopropyltrimethylammonium bromide derivatization coupled with ultra performance liquid chromatography high resolution mass spectrometry...
February 11, 2019: Journal of Separation Science
Ke Wang, Huiyun Zeng, Yi Zhang, Xiujuan Xie, Zhenfeng Yue, Wei Zhang, Chujun Fu, Laicheng Luo, Huajun Fan
A novel method for hierarchical screening of illegal adulterants in Fur seal ginseng pills products was developed by multi-dimensional fingerprint profiling analysis. fingerprint feature of the samples was acquired by HPLC analysis of 11 batches of samples with diode array detector and fluorescence detector, and then potential illegal adulterants including phosphodiesterase type-5 inhibitors, androgens, α receptor antagonists and yohimbine, were further separated at multiple wavelengths to reduce or remove interferences from sample matrix for highlight their chromatographic characteristics...
February 11, 2019: Journal of Separation Science
Enrico Gerace, Denise Caneparo, Federica Borio, Alberto Salomone, Marco Vincenti
Most routine practices for drugs-of-abuse testing do not include screening procedures for new psychoactive substances, despite their increasing diffusion, preventing clear knowledge of the real consumption of these drugs in the populations. To make up for this shortcoming, a GC-MS method was developed for the simultaneous determination of 18 synthetic cathinones and one amphetamine-like compound in human urine. The sample preparation was based on liquid-liquid extraction under alkaline condition followed by derivatization with trifluoroacetic anhydride...
February 11, 2019: Journal of Separation Science
Tiefeng Wang, Ruiqi Zhang, Di Li, Ping Su, Yi Yang
In this study, magnetized MOF-74 (Ni) was prepared using an ultrasound-assisted synthesis method. This novel functional magnetic adsorbent was characterized using various techniques. Using the prepared material as adsorbents, a magnetic solid-phase extraction method coupled with HPLC was proposed for determining four phthalate esters in Chinese liquor samples. The extraction parameters, including solution pH, adsorbent amount, extraction time, and eluent type and volume, were optimized. Under the optimized conditions, proposed method showed good linearity within the range of 1...
February 8, 2019: Journal of Separation Science
Xiang Cui, Yu-Meng Shen, Shu Jiang, Da-Wei Qian, Er-Xin Shang, Zhen-Hua Zhu, Jin-Ao Duan
In this study, a rapid and highly sensitive ultra performance liquid chromatography-triple quadrupole mass spectrometer method with the mobile phases of acetonitrile and 0.1% aqueous formic acid was established and successfully applied to comparatively analyze main active components after their compatibility. Besides, the effects of Scutellariae Radix, Coptidis Rhizoma and combined extracts on type 2 diabetic rats induced by high-fat diet along with low dose of streptozocin were investigated. Under the optimized chromatographic conditions, good separation of seven target components was achieved within 12 min...
February 7, 2019: Journal of Separation Science
Batoul Arabsorkhi, Hassan Sereshti, Alireza Abbasi
A new composite nanofiber of polyacrylonitrile doped with copper benzene-1,3,5-tricarboxylate metal-organic framework was fabricated by electrospinning and used as a microsorbent in solid phase extraction of trace tetracycline. The chemical structure of adsorbent was studied by X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, Brunauer-Emmett-Teller surface area analysis and Barrett-Joyner-Halenda pore size and volume analysis techniques. The significant parameters of the method including desorption solvent kind and volume, adsorbent mass, pH, and salt percentage were investigated...
February 7, 2019: Journal of Separation Science
Vitória L Louros, Diana L D Lima, Jorge H Leitão, Valdemar I Esteves, Helena G Nadais
Estrone, 17β-estradiol and 17α-ethinylestradiol are increasingly recognised as important micropollutants to be monitored in wastewater treatment plants. These estrogens are retained onto sludge due to their high adsorption and since they are largely used in land applications, the monitoring of these chemicals in sludge samples is of great importance. This study describes a method for the determination of estrone and 17α-ethinylestradiol in fresh sludge samples. After spiking fresh digested sludge with estrone and 17α-ethinylestradiol and maintaining in contact during 5, 30 and 60 min, the freeze-dried samples were subjected to ultrasonic liquid extraction, with methanol and acetone, and analysed by high-performance liquid chromatography with fluorescence detection...
January 31, 2019: Journal of Separation Science
Zhuo Xu, Xinxin Dai, Shulan Su, Hui Yan, Sheng Guo, Dawei Qian, Jingao Duan
In the process of planting and harvesting of Rehmannia glutinosa, only the underground part is used, and a large number of stems and leaves that are considered non-medicinal parts are usually discarded. Recent studies have shown that the chemical components in the leaves are similar to those identified in the roots. In this study, we selected leaves and roots from Rehmannia glutinosa at different growth stages and leaves from different cultivation regions to investigate the dynamic accumulation of 3 kinds of glycosides (catalpol, acteoside and ajugol), 6 kinds of carbohydrates (rhamnose, fructose, sucrose, melibiose, stachyose, and verbascose) and acidic and neutral polysaccharides via rapid quantitative analysis technology, including ultra-performance liquid chromatography triple quadrupole tandem mass spectrometry, HPLC and UV...
January 31, 2019: Journal of Separation Science
Nasim Baimani, Parviz Aberoomand Azar, Syed Waqif Husain, Homayon Ahmad Panahi, Ali Mehramizi
This study introduced a developed approach for the use of polyester dendrimer during the imprinting process to raise the number of recognized sites in the polymer matrix and improve its identification ability. Photo-responsive molecular imprinting polymers were synthesized on modified magnetic nano-particles involving polyester dendrimer which uses the reactivity between allyl glycidyl ether and acrylic acid for the high-yielding assembly by surface polymerization. The photo responsive molecular imprinting polymers were constructed using methylprednisoloneacetate as the template, water-soluble azobenzene involving 5-[(4, 3-(methacryloyloxy) phenyl) diazenyl] dihydroxy aniline as the novel functional monomer, and ethylene glycol dimethacrylate as the cross-linker...
January 28, 2019: Journal of Separation Science
Habib Razmi, Sara Manafi Khoshmanesh
A layered by layered graphenized graphite/ polyaniline coating was fabricated on commercial pencil lead substrate by an in situ facile, fast and efficient electrochemical procedure. The electrodeposited polyaniline film on surface confined graphene structure can integrate the advantages of the both layers that were used for solid phase microextraction. Effective experimental parameters in electrochemical production of graphene nanosheets and electropolymerization of aniline were optimized. The prepared fiber was used for extraction and determination of four polycyclic aromatic hydrocarbons: phenanthrene, anthracene, fluoranthene and pyrene in aqueous samples by high performance liquid chromatography...
January 25, 2019: Journal of Separation Science
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