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ion chromatography

Yan-Ru Liu, Zhi-Shu Tang, Jin-Ao Duan, Xiao-Chun Sun, Zhong-Xing Song, Xin-Bo Shi, Yang Lv, Zhao Zhang, Da-Wei Qian
To explore the flavor and meridian tropism classification of Callianthemum taipaicum by principal components analysis(PCA) and partial least square analysis(PLS). Meanwhile,to establish a high performance liquid chromatography-tandem mass spectrometry(HPLC-ESI-MS) method for the simultaneous determination of 55 active components from 13 kinds of Ranunculaceae of Chinese traditional herbs. Samples were separated on HPLC system by Agilent 5 TC-C₁₈(2)(4.6 mm×250 mm,5 μm)column and eluted with acetonitrile and 0...
January 2018: Zhongguo Zhong Yao za Zhi, Zhongguo Zhongyao Zazhi, China Journal of Chinese Materia Medica
Wen-Jing Zhao, Mo-Ran Huang, Zhan-Peng Shang, Zi-Jian Wang, Zhi-Bin Wang, Jia-Yu Zhang
An efficient method of ultra-high performance liquid chromatography coupled with linear ion trap-Orbitrap (UHPLC-LTQ-Orbitrap) mass spectrometer was established to elucidate the in vivo metabolites of tanshinone Ⅰ and tanshinone ⅡA in rats. Urine and plasma samples were collected after oral gavage. After processing biological sample by solid phase extraction, Waters ACQUITY HPLC BEH C₁₈ column (2.1 mm×100 mm, 1.7 μm) was used with 0.1% formic acid (A) - acetonitrile (B) solution as the mobile phase for gradient elution...
January 2018: Zhongguo Zhong Yao za Zhi, Zhongguo Zhongyao Zazhi, China Journal of Chinese Materia Medica
Sunil Ghatge, Youri Yang, Woo-Young Song, Tae-Young Kim, Hor-Gil Hur
In the present study, the gene encoding a multicopper oxidase, more precisely a laccase from the thermoalkaliphilic aerobic bacterium Caldalkalibacillus thermarum strain TA2.A1 (CtLac), was cloned and expressed in Escherichia coli. CtLac is a monomeric protein with a molecular weight of 57 kDa as determined by native polyacrylamide gel electrophoresis. The optimum pH and temperature for 2,6-dimethoxyphenol (2,6-DMP) oxidation were 8.0 and 70 °C, respectively. The kinetic constants Km and kcat for 2,6-DMP were of 200 μM and 23 s-1 , respectively...
March 19, 2018: Applied Microbiology and Biotechnology
Atsushi Hirano, Kazuki Iwashita, Shun Sakuraba, Kentaro Shiraki, Tsutomu Arakawa, Tomoshi Kameda
Ion-exchange chromatography and multimodal ion-exchange chromatography are widely used for the separation of small molecules, peptides and proteins. Salts generally attenuate the electrostatic interactions between charged moieties of solutes and those of resins through electrostatic screening. However, little is known about how salts affect the interaction between the uncharged moieties of the solutes, such as aromatic moieties, and the charged moieties of the resins. In this study, we used alkyl gallates as model aromatic solutes to investigate the interaction mechanism of aromatic moieties with multimodal and conventional ion-exchange resins...
March 6, 2018: Journal of Chromatography. A
Mathijs Baert, Steven Martens, Gert Desmet, André J de Villiers, Filip E Du Prez, Frederic Lynen
Comprehensive two-dimensional liquid chromatography (LC×LC) allows for substantial gains in theoretical peak capacity in the field of liquid chromatography. However, in practice theoretical performance is rarely achieved due to a combination of undersampling, orthogonality and refocusing issues prevalent in many LC×LC applications. This is intricately linked to the column dimensions, flow rates and mobile phase compositions used, where in many cases incompatible or strong solvents are introduced in the second-dimension (2D) column, leading to peak broadening and the need for more complex interfacing approaches...
March 18, 2018: Analytical Chemistry
Bo Zhuang, Zhi-Ming Bi, Zi-Yuan Wang, Li Duan, Chang-Jiang-Sheng Lai, E-Hu Liu
Platycladi Cacumen (PC) is a traditional Chinese medicine used for the treatment of hemorrhages, cough, asthma and hair loss. To get a better understanding of the chemical constituents in PC, ultra-high performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry (UPLC-Q-TOF-MS/MS) and diagnostic ion filtering strategy were firstly employed for chemical profiling of PC. A total of 43 compounds including organic acids and derivatives, flavonoids as well as phenylpropanolds were unambiguously or reasonably identified...
March 9, 2018: Journal of Pharmaceutical and Biomedical Analysis
Adriana Ferreira Lopes Vilela, Cláudia Seidl, Juliana Maria de Lima, Carmen Lúcia Cardoso
Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) are key cholinesterase enzymes responsible for the hydrolysis of acetylcholine into choline and acetic acid, an essential process for the restoration of the cholinergic neuron. The loss of cholinergic function in the central nervous system contributes to the cognitive decline associated with advanced age and Alzheimer's disease (AD). Inhibitions assays represent a significant role in the drug discovery process. Herein, we describe an improved label free method to screen and characterize new BChE ligands...
March 14, 2018: Analytical Biochemistry
Marie Mardal, Petur Weihe Dalsgaard, Bing Qi, Christian Brinch Mollerup, Pieter Annaert, Kristian Linnet
The main analytical targets of synthetic cannabinoids are often metabolites. With the high number of new psychoactive substances entering the market, suitable workflows are needed for analytical target identification in biological samples. The aims of this study were to identify the main metabolites of the synthetic cannabinoids, AMB-CHMICA and 5C-AKB48, using an in silico-assisted workflow with analytical data acquired using ultra-high-performance liquid chromatography-(ion mobility spectroscopy)-high resolution-mass spectrometry in data-independent acquisition mode (UHPLC-(IMS)-HR-MSE )...
March 10, 2018: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
Zhao-Lian Lu, Ying-Jian Chen, Xin-Yan Jing, Na-Na Wang, Ting Zhang, Cheng-Jin Hu
BACKGROUND Papillary thyroid cancer (PTC) is currently the most commonly diagnosed endocrine malignancy. In addition, the sex- and age-adjusted incidence of PTC has exhibited a greater increase over the last 2 decades than in many other malignancies. Thus, discovering noninvasive specific serum biomarker to distinguish PTC from cancer-free controls in its early stages remains an important goal. MATERIAL AND METHODS Serum samples from 88 PTC patients and 80 cancer-free controls were randomly allocated into training or validation sets...
March 17, 2018: Medical Science Monitor: International Medical Journal of Experimental and Clinical Research
Ivan Notardonato, Elisabetta Salimei, Mario Vincenzo Russo, Pasquale Avino
Baby foods are either a soft, liquid paste or an easily chewed food since babies lack developed muscles and teeth to chew effectively. Babies typically move to consuming baby food once nursing or formula is not sufficient for the child's appetite. Some commercial baby foods have been criticized for their contents. This article focuses on the simultaneous determination of organophosphorus pesticides and phthalates by means of a method based on ultrasound-vortex-assisted liquid-liquid microextraction coupled with gas chromatography-ion trap mass spectrometry (GC-IT/MS)...
March 17, 2018: Analytical and Bioanalytical Chemistry
Anetta Zioła-Frankowska, Marcin Frankowski
The research presents the first results of aluminium speciation analysis in aqueous extracts of individual plant parts of Betula pendula and soil samples, using High Performance Ion Chromatography with Diode Array Detection (HPIC-DAD). The applied method allowed us to carry out a full speciation analysis of aluminium in the form of predominant aluminium-fluoride complexes: AlF(x=2,3,4) (3-x) (first analytical signal), AlF2+ (second analytical signal) and Al3+ (third analytical signal) in samples of lateral roots, tap roots, twigs, stem, leaf and soil collected under roots of B...
March 2018: Journal of Environmental Sciences (China)
Tahereh Shojaeimehr, Farshad Rahimpour, Michael Schwarze, Jens-Uwe Repke, Hamid Reza Godini, Günter Wozny
The present study evaluates the capability of ion exclusion chromatography (IEC) of short chain aliphatic carboxylic acids using a cation exchange column (8% sulfonated cross-linked styrene-divinylbenzene copolymer) in different experimental conditions. Since one of the prerequisites to the development of an efficient carboxylic acid separation process is to obtain the optimum operational conditions, response surface methodology (RSM) was used to develop an approach to evaluate carboxylic acids separation process in IEC columns...
March 8, 2018: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
Heike Bittersohl, Björn Schniedewind, Uwe Christians, Peter B Luppa
Therapeutic drug monitoring (TDM) of the immunosuppressive drug tacrolimus is essential to avoid side effects and rejection of the allograft after transplantation. In the blood circulation, tacrolimus is largely located inside erythrocytes or bound to plasma proteins and less than 0.1% is protein-unbound (free). One basic principle of clinical pharmacology is that only free drug is pharmacologically active and monitoring this portion has the potential to better reflect the drug effect than conventional measurements of total tacrolimus in whole blood...
March 7, 2018: Journal of Chromatography. A
Charles M Nichols, Jody C May, Stacy D Sherrod, John A McLean
The field of ion mobility-based omics studies requires high-quality collision cross section (CCS) libraries to effectively utilize CCS as a molecular descriptor. Absolute CCS values with the highest precision are obtained on drift tube instruments by measuring the drift time of ions at multiple drift voltages, commonly referred to as a 'stepped field' experiment. However, generating large scale absolute CCS libraries from drift tube instruments is time consuming due to the current lack of high-throughput methods...
March 15, 2018: Analyst
Moayad Saad, Sebastiaan Bijttebier, An Matheeussen, Evy Verbueken, Casper Pype, Christophe Casteleyn, Chris Van Ginneken, Louis Maes, Paul Cos, Steven Van Cruchten
This article represents data regarding a study published in Toxicology in vitro entitled " in vitro CYP-mediated drug metabolism in the zebrafish (embryo) using human reference compounds" (Saad et al., 2017) [1]. Data were acquired with ultra-performance liquid chromatography - accurate mass mass spectrometry (UPLC-amMS). A full spectrum scan was conducted for the testosterone (TST) metabolites from the microsomal stability assay in zebrafish and humans. The microsomal proteins were extracted from adult zebrafish male (MLM) and female (FLM) livers, whole body homogenates of 96 h post fertilization larvae (EM) and a pool of human liver microsomes from 50 donors (HLM)...
February 2018: Data in Brief
Pierluigi Delmonte, Andrea Milani, Shivani Bhangley
Several marine oils and seed oils on the market contain relevant quantities of stearidonic acid (18:4n-3, SDA). The formation of 18:4n-3 trans fatty acids (tFA) during the refining of these oils necessitates the development of a method for their quantification. In this study, 18:4n-3 was isolated from Ahiflower and isomerized to obtain its 16 geometric isomers. The geometric isomers of 18:4n-3 were isolated by silver ion HPLC (Ag+ -HPLC) and characterized by partial reduction with hydrazine followed by gas chromatography analysis...
March 14, 2018: Lipids
Michael Mccullagh, David Douce, Els Van Hoeck, Séverine Goscinny
A method using Ion Mobility Mass Spectrometry (IM-MS) and collision induced dissociation (CID) coupled with micro flow Ultra High Performance Chromatography (UPLC-IM-MS) has been developed to screen for steviol glycosides. Travelling wave ion mobility was used to determine rotationally averaged collision cross sections in nitrogen buffer gas (TWCCSN2). To illustrate the evolving applicability of ion mobility screening, the analytical approach was initially developed and applied to the analysis of a steviol/steviol glycoside spiked chocolate spread extract...
March 14, 2018: Analytical Chemistry
Marta Menicatti, Marco Pallecchi, Silvia Bua, Daniela Vullo, Lorenzo Di Cesare Mannelli, Carla Ghelardini, Fabrizio Carta, Claudiu T Supuran, Gianluca Bartolucci
Rheumatoid arthritis (RA) is a chronic inflammatory disease caused by a faulty autoimmune response. Recently, it was reported that some human carbonic anhydrases (CAs) isoforms are overexpressed in inflamed synovium of RA patients. New CA inhibitors (CAIs) incorporating CA-binding moiety and the cyclooxygenase inhibitor tail (nonsteroidal anti-inflammatory drug [NSAID] type) were studied. The aim of this work is the evaluation of the chemical stability of NSAID - CAI hybrids towards spontaneous or enzymatic hydrolysis by LC-MS/MS...
December 2018: Journal of Enzyme Inhibition and Medicinal Chemistry
Youssef Rouphael, Giampaolo Raimondi, Luigi Lucini, Petronia Carillo, Marios C Kyriacou, Giuseppe Colla, Valerio Cirillo, Antonio Pannico, Christophe El-Nakhel, Stefania De Pascale
Interest in the role of small bioactive molecules (< 500 Da) in plants is on the rise, compelled by plant scientists' attempt to unravel their mode of action implicated in stimulating growth and enhancing tolerance to environmental stressors. The current study aimed at elucidating the morphological, physiological and metabolomic changes occurring in greenhouse tomato (cv. Seny) treated with omeprazole (OMP), a benzimidazole inhibitor of animal proton pumps. The OMP was applied at three rates (0, 10, or 100 μM) as substrate drench for tomato plants grown under nonsaline (control) or saline conditions sustained by nutrient solutions of 1 or 75 mM NaCl, respectively...
2018: Frontiers in Plant Science
Inga Markeviciute, Wolfgang Frenzel
Sample preparation is a key issue in the analysis of many real samples using ion chromatography (IC). One of the many means of sample preparation that has received considerable attention in recent years is the stopped-flow in-line dialysis approach hyphenated to IC. Using appropriate dialysis membranes undesirable high-molecular weight compounds, colloids and dispersed particulate matter are retained whereas the analyte ions pass through the membrane and are separated and quantified by IC. However, in the many papers about analytical use of in-line dialysis (not only in connection with IC) the retention of undesirable compounds has never been quantified...
August 3, 2018: Analytica Chimica Acta
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