87,603 results match your criteria column chromatography

Determination of Seven Organic Impurities in FD&C Yellow No. 6 by Ultra-High-Performance Liquid Chromatography.

J AOAC Int 2021 Jul 29. Epub 2021 Jul 29.

Office of Cosmetics and Colors, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, MD, 20740, USA.

Background: The U.S. Food and Drug Administration (FDA) batch certifies FD&C Yellow No. Read More

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Isolation, screening, and identification of key components having intense insect repellent activity against Plodia interpunctella from 4 different medicinal plant materials.

J Sci Food Agric 2021 Jul 29. Epub 2021 Jul 29.

Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul, 02841, Republic of Korea.

Background: Global warming and indiscriminate use of pesticides increased the propagation of the stored-product insect pests, leading to the enormous losses in the agriculture and food industries. The most used insect repellents were synthetic derivatives, however, these have an adverse effect on human health as well as on the environment. Therefore, we tried to find materials with insect repellent activity in natural products. Read More

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Lipidomics of Environmental Microbial Communities. II: Characterization Using Molecular Networking and Information Theory.

Front Microbiol 2021 12;12:659315. Epub 2021 Jul 12.

Department of Marine Microbiology and Biogeochemistry, NIOZ Royal Institute for Sea Research, Texel, Netherlands.

Structurally diverse, specialized lipids are crucial components of microbial membranes and other organelles and play essential roles in ecological functioning. The detection of such lipids in the environment can reveal not only the occurrence of specific microbes but also the physicochemical conditions to which they are adapted to. Traditionally, liquid chromatography coupled with mass spectrometry allowed for the detection of lipids based on chromatographic separation and individual peak identification, resulting in a limited data acquisition and targeting of certain lipid groups. Read More

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Simultaneous enantio- and diastereo-selective high-performance liquid chromatography separation of paroxetine on an immobilized amylose-based chiral stationary phase under green reversed-phase conditions.

J Chromatogr A 2021 Jul 14;1653:462406. Epub 2021 Jul 14.

National Centre for the Control and Evaluation of Medicines, Chemical Medicines Unit, Istituto Superiore di Sanità (ISS), Viale Regina Elena 299, 00161, Rome, Italy. Electronic address:

A simple and green high-performance liquid chromatography method for the separation of paroxetine from its enantiomeric and diastereomeric impurities has been developed. The simultaneous chromatographic resolution was carried out on the amylose-based Chiralpak IA-3 chiral stationary phase using the mixture ethanol-water-diethylamine 80:20:0.1 (v/v/v) as a mobile phase. Read More

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Separation of monomeric and dimeric phenolic compounds in lignosulphonate lignin on different stationary phases using ultrahigh-performance supercritical fluid chromatography.

J Chromatogr A 2021 Jul 14;1653:462408. Epub 2021 Jul 14.

Lund University, Department of Chemistry, Centre for Analysis and Synthesis, P.O. Box 124, SE-22100 Lund, Sweden. Electronic address:

Lignin is a promising renewable resource and its valorization could help to reduce our dependency on fossil carbon resources. Especially the production of small molecular weight and economically valuable compounds, such as vanillin, are of interest. A good separation of the sample components is crucial for a confident identification of compounds in complex sample mixtures using for instance mass spectrometry. Read More

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Patterns of protein adsorption in ion-exchange particles and columns: Evolution of protein concentration profiles during load, hold, and wash steps predicted for pore and solid diffusion mechanisms.

J Chromatogr A 2021 Jul 14;1653:462412. Epub 2021 Jul 14.

Department of Biotechnology, BOKU Vienna, Vienna, Austria. Electronic address:

Elucidation of protein transport mechanism in ion exchanges is essential to model separation performance. In this work we simulate intraparticle adsorption profiles during batch adsorption assuming typical process conditions for pore, solid and parallel diffusion. Artificial confocal laser scanning microscopy images are created to identify apparent differences between the different transport mechanisms. Read More

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Rapid Formation of Polymer Frits in Fused Silica Capillaries Using Spatially defined Thermal Free-Radical Initiated Polymerization.

Sep Sci Plus 2018 Nov 19;1(11):753-758. Epub 2018 Nov 19.

Department of Chemistry and Biochemistry, University of Arizona, Tucson, 85721, AZ.

Column preparation in capillary chromatography commonly relies upon the generation of on-column porous frits. Here, we report a simple, robust and low-cost approach for preparing polymer frits on-column, in a rapid and spatially controlled manner using thermal free-radical initiated polymerization. In this approach, a simple, temperature-controlled heating apparatus is positioned adjacent to a 100 m i. Read More

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November 2018

An Ion Chromatography Method for Simultaneous Quantification of Chromate, Arsenate, Selenate, Perchlorate, and Other Inorganic Anions in Environmental Media.

Environ Eng Sci 2021 Jul 22;38(7):626-634. Epub 2021 Jul 22.

School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, Arizona, USA.

Chromium (Cr) (VI) is a toxic, mutagenic, and carcinogenic water pollutant. The standard ion chromatography (IC) method for quantification of Cr (VI) in water samples is Environmental Protection Agency Method 218.7, which requires postcolumn derivatization with 1,5-diphenylcarbazide and UV-Vis spectroscopy detection. Read More

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Tissue N-Glycan Analysis Using LC-MS, MS/MS, and MS.

Noriko Suzuki

Curr Protoc 2021 Jul;1(7):e200

Graduate School of Science and Technology, Niigata University, Niigata, Japan.

Tissue glycans usually contain various structures, from simple to highly complicated, in different quantities. N-Glycans are particularly heterogeneous, with up to pentaantennary structures, different branch sequences, and several isomeric structures. 2-Aminopyridine (PA) tagging on released N-glycans is useful for separating isomers and to quantitatively analyze both the major and minor glycan structures in tissues using reversed-phase liquid chromatography (LC)-mass spectrometry (MS) and MS/MS analysis. Read More

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Thin-Layer Chromatography Gradient Optimization Strategy for Wet Load Adsorption Flash Chromatography.

J Chromatogr Sci 2021 Jul 27. Epub 2021 Jul 27.

Department of Pharmaceutical Chemistry, Drug Analysis and Radiopharmacy, Medical University of Lodz, ul. Muszyńskiego 1, 90-151 Łódź, Poland.

Chromatography is one of the most popular methods for the separation of compounds in modern pharmaceutical industry and science. Despite the extensive use of the reversed phase chromatography in analytical and preparative applications, the normal phase adsorption chromatography has a special place in purifying post-reaction mixtures or the separation of natural extracts, especially in wet load mode, because of simplicity and high velocity of preparation. Complex mixtures, more difficult to separate, require gradient methods to obtain better results of separations. Read More

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Tailored nanodisc immobilization for one-step purification and reconstitution of cytochrome P450: A tool for membrane proteins' hard cases.

J Sep Sci 2021 Jul 26. Epub 2021 Jul 26.

State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, China.

A novel nanodisc-based immobilization method was developed for high-efficient purification and reconstitution of cytochrome P450 in one step. Using membrane scaffold protein containing a histidine tag, charged-nanodiscs were prepared in the form of self-assembly of lipid-protein nanoparticles. Their properties including the particle diameter and its distribution, and Zeta potential were controlled well by adjusting molar ratios of phospholipids to membrane scaffold protein. Read More

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[Determination of furan in canned foods and packaged beverages by headspace gas chromatography-mass spectrometry].

Wei Sheng Yan Jiu 2021 Jul;50(4):641-645

Beijing Center for Disease Prevention and Control, Beijing Center for Prevention Medicine Research, Beijing 100013, China.

Objective: A headspace gas chromatography-mass spectrometry(HS-GC-MS) method for the analysis of furan in canned foods and packaged beverages was established.

Methods: The furan was extracted from the samples by headspace method. D_4-furan was used as internal standard and separated on a HP-Plot Q(30 m×0. Read More

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[Detect 15 pesticides fungicide in edible fungi by multiplug filtration clean-up pretreatment technology with ultra-high performance liquid chromatography-tandem mass spectrometry].

Wei Sheng Yan Jiu 2021 Jul;50(4):633-640

Beijing Center for Disease Control and Prevention, Beijing 100013, China.

Objective: To establish a method for determination of 15 pesticides residue in edible fungi by multiplug filtration clean-up(m-PFC) pretreatment technique with ultra-high performance liquid chromatography-tandem triple quadruple mass spectrometry(UPLC-MS/MS).

Methods: The interferences of edible fungus samples were removed by extracting with acetonitrile and filtration type extraction column, which were fat, carbohydrates, water-soluble vitamins. Samples were separated with column of Waters ACQUITY UPLC®HSS T3(2. Read More

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[Determination of chlorate and perchlorate in infant formula by ultra-high performance liquid chromatography-tandem mass spectrometry].

Wei Sheng Yan Jiu 2021 Jul;50(4):625-632

Fujian Provincial Key Laboratory of Zoonosis Research, Fujian Center for Disease Control & Prevention, Fuzhou 350001, China.

Objective: To establish a method for determination of perchlorate and chlorate in infant formula by ultra-high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).

Methods: Chlorate-~(18)O_3 and perchlorate-~(18)O_4 were added to the samples, and the filtrate was collected and analyzed by UPLC-MS/MS by vortex mixing, extraction, centrifugation and filtration. The mobile phase was 20 mmol/L ammonium formate and acetonitrile. Read More

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[Determination of quinoxalines veterinary drug residues in food products of animal origin by high performance liquid chromatography-tandem mass spectrometry].

Hua Yin Weiming Lu

Wei Sheng Yan Jiu 2021 Jul;50(4):620-624

Changshu Provincial Center for Disease Control and Prevention, Changshu 215500, China.

Objective: To establish a high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)method for simultaneous determination of olaquindox, quinoxaline-2-carboxylic acid, 3-methyl-quinoxaline-2-carboxylic acid in food products of animal origin.

Methods: Samples were extracted with ethyl acetate-0.1 mol/L sodium dihydrogen phosphate(1∶9, V/V) solution in water bath at 40 ℃, purified by solid phase extraction column(olaquindox uses HLB SPE cartridge, quinoxaline-2-carboxylic acid and 3-methyl-quinoxaline-2-carboxylic acid use MAX SPE cartridge), evaporated by concentrator, and dissolved by mobile phase. Read More

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[Determination of vitamin A, vitamin E isomers and cholesterol in foods by reversed-phase high-performance liquid chromatography].

Wei Sheng Yan Jiu 2021 Jul;50(4):615-619

Center for Disease Control and Prevention of Shaanxi Province, Xi'an 710054, China.

Objective: To establish a method for simultaneous analysis of vitamin A, three vitamin E isomers and cholesterol in meat products by reversed-phase high-performance liquid chromatography. This method is used to determine the contents of the corresponding nutrients in several meat products.

Methods: The sample was pretreated with saponification and liquid-liquid extraction, then separated on Waters Symmetry C_(18) column(4. Read More

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SAPT, a Fast and Efficient Approach for Simultaneous Profiling of Protein N- and C-Terminome.

Anal Chem 2021 Jul 23. Epub 2021 Jul 23.

Shanghai Cancer Center and Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, P. R. China.

Protein termini play pivotal roles in various biological processes. Although several terminomic strategies have been proposed for the analysis of protein N-termini or protein C-termini separately, few can analyze both ends of proteins at the same time. Herein, we developed a workflow, termed Simultaneous Analysis of Protein N- and C-Terminome (SAPT) based on strong cation exchange chromatography (SCX) fractionation. Read More

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Bridging the Polar and Hydrophobic Metabolome in Single-Run Untargeted Liquid Chromatography-Mass Spectrometry Dried Blood Spot Metabolomics for Clinical Purposes.

J Proteome Res 2021 Jul 23. Epub 2021 Jul 23.

National Unit for Screening and Diagnosis of Congenital Pediatric Metabolic Disorders, Department of Medical Biochemistry, Oslo University Hospital, Rikshospitalet, Sognsvannsveien 20, Oslo 0372, Norway.

Dried blood spot (DBS) metabolite analysis is a central tool for the clinic, e.g., newborn screening. Read More

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Insight into purification of monoclonal antibodies in industrial columns studies of Protein A binding capacity by ATR-FTIR spectroscopy.

Analyst 2021 Jul 23. Epub 2021 Jul 23.

Department of Life Sciences, Imperial College London, South Kensington Campus, SW7 2AZ, London, UK.

Therapeutic monoclonal antibodies (mAbs) are effective treatments for a range of cancers and other serious diseases, however mAb treatments cost on average ∼$100 000 per year per patient, limiting their use. Currently, industry favours Protein A affinity chromatography (PrAc) as the key step in downstream processing of mAbs. This step, although highly efficient, represents a significant mAb production cost. Read More

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Structural characterization of novel arabinoxylan and galactoarabinan from citron with potential antitumor and immunostimulatory activities.

Carbohydr Polym 2021 Oct 11;269:118331. Epub 2021 Jun 11.

College of Food and Bioengineering, South China University of Technology, Guangzhou 510640, China. Electronic address:

This study aimed to extract polysaccharides from citron and analyze their structures and potential bioactivities. Two novel polysaccharides CM-1 and CM-2 were purified from citron by DEAE-Sepharose Fast Flow and Sephadex G-100 column chromatography. Monosaccharide composition, linkage and NMR data were used to infer their sugar chains composition. Read More

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October 2021

Structural characterization and mechanisms of macrophage immunomodulatory activity of a pectic polysaccharide from Cucurbita moschata Duch.

Carbohydr Polym 2021 Oct 2;269:118288. Epub 2021 Jun 2.

College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China; National Engineering Research Center for Fruits and Vegetables Processing, Beijing 100083, China. Electronic address:

A pectic polysaccharide (named CMDP-4b) with a molecular weight of 31.97 kDa was extracted from Cucurbita moschata Duch and purified by column chromatography. On the basis of methylation, Fourier-transform infrared, monosaccharide composition, and one- and two-dimensional nuclear magnetic resonance spectroscopy analyses, the structure of CMDP-4b was determined to be composed of an α-1,4-linked homogalacturonan backbone, which was slightly acetylated and highly methyl-esterified, and branched at the O-3 position of the →4)-α-D-GalpA-6-OMe-(1→. Read More

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October 2021

Using multimodal chromatography for post-conjugation antibody-drug conjugate purification: A methodology from high throughput screening to in-silico process development.

J Chromatogr A 2021 Jun 30;1653:462378. Epub 2021 Jun 30.

Purification Process Sciences, BioPharmaceuticals Development, R&D, AstraZeneca, Gaithersburg, USA.

In this paper, a methodology for the development of a multimodal chromatography process is presented that is aimed at removal of under-conjugated antibody-drug conjugate (ADC) species. Two ADCs are used as case studies: One ADC results from site-directed conjugation to inserted cysteine residues and has a drug-to-antibody ratio (DAR) of two, the other is the product of conjugation to interchain disulfide bonds with a DAR of eight. First, filter plate screening studies are designed for the unconjugated antibody and the ADCs. Read More

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Development and validation of an LC-MS/MS method to quantify the bromodomain and extra-terminal (BET) inhibitor JQ1 in mouse plasma and brain microdialysate: Application to cerebral microdialysis study.

J Pharm Biomed Anal 2021 Jul 21;204:114274. Epub 2021 Jul 21.

Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, TN, USA. Electronic address:

JQ1, is a cell-permeable small-molecule inhibitor of bromodomain and extra-terminal protein (BET) function with reportedly good CNS penetration, however, unbound and pharmacologically active CNS JQ1 exposures have not been characterized. Additionally, no quantitative bioanalytical methods for JQ1 have been described in the literature to support the CNS penetration studies. In the present article, we discuss the development and validation of a sensitive and reliable liquid chromatography-tandem mass spectrometry (LC-MS/MS) quantitative methods to determine JQ1 in mouse plasma and brain microdialysate. Read More

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Simultaneous Determination of 78 Compounds of Extract by Supercritical CO-Extraction and HPLC-ESI-MS/MS Spectrometry.

Biochem Res Int 2021 6;2021:9957490. Epub 2021 Jul 6.

N. I. Vavilov All-Russian Institute of Plant Genetic Resources, B. Morskaya 42-44, Saint-Petersburg 190000, Russia.

The plant L. of family was extracted using the supercritical CO-extraction method. Several experimental conditions were investigated in the pressure range of 200-500 bar, with the used volume of cosolvent ethanol in the amount of 1% in the liquid phase at a temperature in the range of 31-70°C. Read More

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Quantification and discovery of quality control chemical markers for Ba-Bao-Dan by UPLC-MS/MS combined with chemometrics.

J Pharm Biomed Anal 2021 Jul 21;204:114273. Epub 2021 Jul 21.

College of Pharmacy, Fujian Key Laboratory of Chinese Materia Medica, Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian, 350122, China. Electronic address:

Ba-Bao-Dan (BBD) is a well-known Traditional Chinese medicine (TCM) prescription in China. It was first formulated in approximately 1555 AD. As one of the National Protected TCM, it is widely used to treat jaundice, viral hepatitis, cholecystitis, acute urinary tract infection, cancer, and other diseases. Read More

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Development & validation of LC-MS/MS assay for 5-amino-1-methyl quinolinium in rat plasma: Application to pharmacokinetic and oral bioavailability studies.

J Pharm Biomed Anal 2021 Jul 8;204:114255. Epub 2021 Jul 8.

Department of Pharmaceutical Sciences, Texas Southern University, Houston, TX, 77004, United States. Electronic address:

5-Amino-1-methyl quinolinium (5-AMQ) is a potent Nicotinamide N-methyl transferase (NNMT) inhibitor. NNMT is an enzyme that catalyzes the N-methylation of the endogenous substrate nicotinamide, as well as exogenous xenobiotics. NNMT is fundamental to cellular metabolism; NNMT is overexpressed in select tissues (e. Read More

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Comparing the relative robustness of anion exchange and the corresponding mixed-mode chromatography on removing a weakly-bound byproduct: A case study of bispecific antibody purification.

Protein Expr Purif 2021 Jul 22:105948. Epub 2021 Jul 22.

Technology and Process Development (TPD), WuXi Biologics, 288 Fute Zhong Road, Waigaoqiao Free Trade Zone, Shanghai, 200131, China. Electronic address:

A certain impurity may bind weaker or tighter to a particular type of chromatography column (e.g., ion exchange, hydrophobic interaction or mixed-mode) than the target protein, and this forms the basis for separation. Read More

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Short- and medium-chain chlorinated paraffins in human blood serum of Czech population.

Sci Total Environ 2021 Jul 18;797:149126. Epub 2021 Jul 18.

University of Chemistry and Technology, Prague, Faculty of Food and Biochemical Technology, Department of Food Analysis and Nutrition, Technicka 3, 166 28 Prague 6, Czech Republic. Electronic address:

Short- and medium-chain chlorinated paraffins (SCCPs; MCCPs) are widespread environmental pollutants with bioaccumulation potential and adverse effects on human health. The analysis of blood serum is an important strategy to assess the human exposure to various contaminants, including SCCPs and MCCPs. Lately, the information about the exposure of Chinese population has been reported; nevertheless, data on human exposure to SCCPs and MCCPs outside East Asia are still very limited. Read More

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Simplified and Rapid Determination of Primaquine and 5,6-Orthoquinone Primaquine by UHPLC-MS/MS: Its Application to a Pharmacokinetic Study.

Molecules 2021 Jul 19;26(14). Epub 2021 Jul 19.

Clinical Pharmacokinetics and Pharmacogenomics Research Unit, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand.

The method for the determination of primaquine (PQ) and 5,6-orthoquinone primaquine (5,6-PQ), the representative marker for PQ active metabolites, via CYP2D6 in human plasma and urine has been validated. All samples were extracted using acetonitrile for protein precipitation and analyzed using the ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) system. Chromatography separation was carried out using a Hypersil GOLD aQ C column (100 × 2. Read More

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Validated Simultaneous Gradient Ultra-Performance Liquid Chromatographic Quantification of Some Proton Pump Inhibitor Drug Residues in Saudi Pharmaceutical Industrial Wastewater.

Molecules 2021 Jul 19;26(14). Epub 2021 Jul 19.

Pharmaceutical Chemistry Department, College of Pharmacy, Prince Sattam Bin Abdulaziz University, Al Kharj 11942, Saudi Arabia.

Monitoring and quantification of active pharmaceutical ingredients (APIs) in the environment constitute important and challenging tasks, as they are directly associated with human health. Three commonly used proton pump inhibitors (PPIs), namely, omeprazole sodium (OMP), pantoprazole sodium (PNT), and lansoprazole sodium (LNZ) are well separated and quantified using ultra-performance liquid chromatography (UPLC) in pharmaceutical industrial wastewater. The separation of the studied drugs was performed on a stationary phase with a Waters column (100 × 2. Read More

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