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liquidchromatography, etc ; alkaloids; chemical species; drugs; Show all 4 Subjects
Abstract:
... Natural products, especially alkaloids, are one of the most valuable, potential drug leads in drug discovery. As an efficient tool for complex samples, two-dimensional liquid chromatography (2D-LC) has become a powerful means of analysis and separation of natural alkaloids. Method development of 2D-LC is of great importance because it helps to enhance the selectivity, resolution and peak capacity ...
high performance liquidchromatography, etc ; acetaldehyde; acrolein; emissions factor; formaldehyde; smog pollution; tillage; China; Show all 8 Subjects
Abstract:
... Emissions of carbonyl compounds from agricultural machines cannot be ignored. Carbonyl compounds can cause the formation of ozone (O₃) and secondary organic aerosols, which can cause photochemical smog to form. In this study, 20 agricultural machines were tested using portable emission measurement system (PEMS) under real-world tillage processes. The exhaust gases were sampled using 2,4-dinitrophe ...
liquidchromatography, etc ; cannabidiol; cosmetics; isomerization; magnetism; microextraction; nanoparticles; polymers; sorbents; tandem mass spectrometry; tetrahydrocannabinol; Show all 11 Subjects
Abstract:
... An analytical method for the determination of tetrahydrocannabinol (THC) at trace level in cosmetics is presented. As psychoactive compound, the presence of THC in consumer products should be avoided. However, it might be unintentionally present in cannabidiol-rich or hemp-based products by contamination or isomerization of cannabidiol. Due to the low concentrations expected, a sensitive and selec ...
liquidchromatography, etc ; ammonium acetate; capillary electrophoresis; electric potential difference; mycotoxins; tandem mass spectrometry; temperature; wheat; Show all 8 Subjects
Abstract:
... Enniatins (ENN) and beauvericin (BEA) are emerging mycotoxins that have been traditionally determined by liquid chromatography coupled to tandem mass spectrometry (LC–MS/MS). However, to the best of our knowledge, no analytical methods based on capillary electrophoresis (CE)–MS/MS have been reported so far. Due to their non-polar nature, in this work, a non-aqueous CE (NACE) method coupled to quad ...
ultra-performance liquidchromatography, etc ; biosynthesis; cinnamon; diodes; food chemistry; food plants; green tea; mass spectrometry; melanin; Show all 9 Subjects
Abstract:
... Tyrosinase plays a primary role in melanin biosynthesis and enzymatic browning of freshly cut fruits and vegetables. Herein, an on-line ultraperformance liquid chromatography diode array detector biochemical detection (UPLC-DAD-BCD) method was established to identify trace amount potent tyrosinase inhibitors and antibrowning agents in complex mixtures. The tyrosinase inhibition activities of some ...
liquidchromatography, etc ; European Union; adsorption; milk; molecular imprinting; nanofibers; polyamides; polyethylene; polypropylenes; solid phase extraction; sorbents; Show all 11 Subjects
Abstract:
... Advanced solid phase extraction (SPE) fibrous sorbents including polyethylene, polypropylene poly (hydroxybutyrate), and polyamide 6 nanofibers, polycaprolactone microfibers/nanofibers, polycaprolactone microfibers/polyvinylidene difluoride nanofibers, and poly (hydroxybutyrate) microfibers/polypropylene microfibers composites, as well as commercial molecularly imprinted polymers and restricted ac ...
liquidchromatography, etc ; chemometrics; color; food chemistry; isorhamnetin; kaempferol; metabolomics; rapeseed; sinapic acid; solvents; tandem mass spectrometry; Show all 11 Subjects
Abstract:
... In this study, a two-step extraction strategy (TSES) and targeted metabolomics combined with chemometrics was successfully applied for profiling of phenolic compounds in different colored rapeseeds. To this end, organic solvent extraction followed by deep eutectic solvent extraction made up the TSES with improved extraction coverage of free phenolics and enhanced extraction yield of conjugated phe ...
high performance liquidchromatography, etc ; coumarin; derivatization; electrospray ionization mass spectrometry; fluorescence; tandem mass spectrometry; urea; wavelengths; Show all 8 Subjects
Abstract:
... In this paper, we report about the application of a sensitive fluorescent derivatization reagent Coumarin151-N-Hydroxysuccinimidyl Carbamate (Cou151DSC) for amino compounds using high-performance liquid chromatography (HPLC) compatible with ultraviolet (UV), fluorescence detector (FLD) and electrospray ionization - tandem mass spectrometry (ESI-MS/MS)―positive mode. We optimized derivatization pro ...
liquidchromatography, etc ; breakfast; cocoa (beverage); cooking fats and oils; food composition; fortified foods; mass spectrometry; vitamin D; Show all 8 Subjects
Abstract:
... Fortified foods are an important source of dietary vitamin D, since this nutrient occurs naturally in relatively low concentrations in a limited number of foods. Hence, we aimed to investigate the accuracy of the declared vitamin D content of Australian fortified foods. Vitamin D₃, 25-hydroxyvitamin D₃ (25(OH)D₃), vitamin D₂ and 25(OH)D₂ were measured in 30 fortified food samples (edible oil sprea ...
ultra-performance liquidchromatography, etc ; barley; chemical species; diet; food chemistry; mass spectrometry; oats; pesticides; pseudocereals; rye; standard deviation; Show all 11 Subjects
Abstract:
... In this work, the development of an analytical method for the evaluation of a wide variety of pesticide residues in cereals and pseudo-cereals widely consumed has been carried out. A QuEChERS method was used as extraction and clean-up procedure prior to separation and quantification of the target analytes by ultra-high performance liquid chromatography coupled to mass spectrometry using a single q ...
ultra-performance liquidchromatography, etc ; animal husbandry; chemical species; chlorpromazine; fish; food chemistry; hydrolysis; mass spectrometry; metabolites; pork; risk; Show all 11 Subjects
Abstract:
... Chlorpromazine (CPZ) is abused in animal husbandry and can be extensively metabolized in humans and animals. However, the actual monitoring mainly focuses on the parent compound but lacks attention to its metabolites. A method was developed and validated firstly for identification and determination of CPZ and its four major metabolites in animal-derived foods using ultrahigh-performance liquid chr ...
liquidchromatography, etc ; adsorbents; adsorption; detection limit; fluorine; magnetism; mass spectrometry; soil; solid phase extraction; standard deviation; surface area; Show all 11 Subjects
Abstract:
... Novel magnetic and fluorinated porous carbons (M-FPCs) with high fluorine content, large pore volume and specific surface area were first prepared by carbonizing and further fluorinating Fe–Zr bimetal-organic frameworks. The M-FPCs exhibit excellent adsorption performance toward perfluorinated compounds (PFCs), and the maximal adsorption capacity ranges from 518.1 to 919.3 mg g⁻¹ for various PFCs. ...
liquidchromatography, etc ; discriminant analysis; food safety; grapes; mass spectrometry; models; multivariate analysis; prediction; product authenticity; spectrometers; white wines; Show all 11 Subjects
Abstract:
... Instrument comparability is a major prerequisite for the harmonization of non-targeted analytical approaches for food authentication. While non-targeted liquid chromatography coupled with mass spectrometry (LC-MS) is a powerful and widely used technique in authenticity studies, inter-laboratory or instrument comparison exercises are rare. For the first time, in the present study a comparison of tw ...
high performance liquidchromatography, etc ; acetochlor; atrazine; catalytic activity; colorimetry; crop production; food chemistry; fruits; immunoassays; juices; vegetables; voltammetry; Show all 12 Subjects
Abstract:
... Herbicides atrazine and acetochlor are used in crop production. Because of environmental and health hazards with respective maximum contamination levels of 3 and 20 ng/mL, quantifying these herbicides is important when considering presence in foods and vegetables. We utilized two Pd@Pt nanoparticle-amplified immunoassays, a colorimetric Pd@Pt nanoparticle-linked immunosorbent assay (NLISA) and dif ...
high performance liquidchromatography, etc ; acetonitrile; apricots; boscalid; detection limit; food composition; grapes; liquid-liquid extraction; pyraclostrobin; standard deviation; trifloxystrobin; Show all 11 Subjects
Abstract:
... This paper describes the development of extraction and high-performance liquid chromatography with ultraviolet detection methods for the determination of boscalid, pyraclostrobin, and trifloxystrobin. The extraction method includes classical solid-liquid and liquid-liquid extraction methods. The fungicides and the internal standard were separated in less than 6.5 min on an ODS column with acetonit ...
ultra-performance liquidchromatography, etc ; chemometrics; decision support systems; discriminant analysis; flavonoids; food safety; grapes; tandem mass spectrometry; white wines; Show all 9 Subjects
Abstract:
... The use of metabolic fingerprinting combined with advanced chemometric tools for wine authentication has increased in recent years. Although numerous studies, showing different authentication strategies, have been published, rarely any attention has been paid to the stability of used classification models over a longer time period. Here, we present a reliable and robust metabolic fingerprinting-ba ...
liquidchromatography, etc ; adsorption; bioaccumulation; cross-coupling reactions; density functional theory; food chemistry; solid phase microextraction; tandem mass spectrometry; toxicity; Show all 9 Subjects
Abstract:
... The growing detection of emerging perfluoropolyether carboxylic acids (PFECAs) in food has raised considerable concerns about their high persistence, bioaccumulation, and toxicity. In this study, a pyridine-functionalized covalent organic framework (Py-COF) was synthesized by introducing basic pyridyl groups into Br-COF via Heck cross-coupling. According to density functional theory, PFECAs were a ...
high performance liquidchromatography, etc ; adsorbents; adsorption; catalysts; chemical species; chlorophenols; food chemistry; honey; polymers; porous media; solid phase extraction; Show all 11 Subjects
Abstract:
... A new carbazole-based spherical microporous polymer (Car-BDA-POP) was fabricated by employing 4,4′-biphenyldicarboxaldehyde (BDA) and carbazole as monomers via a one-step and non-metal catalyst synthetic approach. It was then explored as an adsorbent for solid-phase extraction (SPE) of some chlorophenols (CPs). Under the optimized extraction conditions, the established Car-BDA-POP-based SPE couple ...
ultra-performance liquidchromatography, etc ; Pampus argenteus; Thunnus obesus; diacylglycerols; food composition; marine fish; mass spectrometry; palmitoleic acid; phospholipids; sardines; seafoods; Show all 11 Subjects
Abstract:
... Palmitoleic acid (POA) is a monounsaturated n-7 fatty acid (16:1 n-7) that is active in modulating cardiovascular and metabolic processes. POA-structured phospholipids, diglycerides, and triglycerides (POA-PL, -DG, -TG) are abundantly present in marine life. In this study, POA and POA-lipids contained in crude lipids in visceral by-products of six seafood products (n = 6 for each sample) were anal ...
liquidchromatography, etc ; chickens; diacylglycerols; docosahexaenoic acid; egg yolk; eicosapentaenoic acid; food composition; lipid composition; lipidomics; lysophosphatidylcholine; phosphatidylethanolamines; tandem mass spectrometry; Show all 12 Subjects
Abstract:
... Chicken egg yolk (EY) can be divided into yolk granule (EYG) and yolk plasma (EYP); they develop individually based on their remarkably different nutritional compositions and properties. However, the differences in lipid profiles between EYG and EYP have not been fully revealed. In this study, quantitative lipidomic analyses of EY, EYG, and EYP were implemented through a liquid chromatography-tand ...