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acetic acid; amino acids; analytical chemistry; chemical species; derivatization; mass spectrometry; metabolites; metabolomics; neuroglia; reversed-phase liquid chromatography; yeast extract
Abstract:
... The vast majority of mass spectrometry (MS)-based metabolomics studies employ reversed-phase liquid chromatography (RPLC) to separate analytes prior to MS detection. Highly polar metabolites, such as amino acids (AAs), are poorly retained by RPLC, making quantitation of these key species challenging across the broad concentration ranges typically observed in biological specimens, such as cell extr ...
acetic acid; adsorbents; atomic absorption spectrometry; chemical species; ionic strength; pH; solid phase extraction; toxicity; toxicology; water pollution; zinc oxide
Abstract:
... Water pollution due to toxic metals may pose a significant effect on the environment and the biota indicating the necessity of careful management of their concentration in the system. On the other hand, a simplified and useable sample preparation technique is required for their trace analysis. In this report, a simple solid-phase extraction procedure was developed for fast extraction and preconcen ...
acetic acid; acetonitrile; antidepressants; chemical species; computer software; digestive tract; honokiol; intragastric administration; liver; models; naringin; oral administration; pharmacokinetics; rats; serotonin; sucrose; tandem mass spectrometry; ultra-performance liquid chromatography
Abstract:
... To reveal the pharmacokinetic process of narirutin, naringin, and honokiol in normal and different courses of liver-stagnation and spleen-deficiency syndrome depressive rats after intragastric administration of Zhi-Zi-Hou-Po decoction (ZZHPD), a rapid ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) method was proposed in this study. Chronic unpredicta ...
... In the present study, a sample pretreatment based on the combination of vortex assisted liquid–liquid extraction and dispersive liquid–liquid microextraction has been proposed for the isolation and preconcentration of three acidic herbicides including fenoxaprop, fluazifop, and haloxyfop from edible oil samples. For this purpose, firstly, the analytes were extracted into sodium hydroxide solution ...
acetic acid; ammonia; ammonium; analytical chemistry; chemical species; electrospray ionization mass spectrometry; hydrogen; methanol; molecular weight; prediction; regression analysis; solvents
Abstract:
... The effect of makeup solvent composition in ultrahigh-performance supercritical fluid chromatography-triple quadrupole mass spectrometry using electrospray ionization was studied using a set of 91 compounds, 3 stationary phases, and 2 organic modifiers of the mobile phase. The 24 tested makeup solvents included pure alcohols and methanol in combination with commonly used additives such as water, f ...
3-hydroxybutyric acid; acetic acid; biomarkers; case studies; chemical species; diabetes; immune response; ketone bodies; metabolomics; mice; risk reduction; tandem mass spectrometry
Abstract:
... Recently, there has been growing interest in short-chain fatty acids (SCFA) and ketone bodies (KB) due to their potential use as biomarkers of health and disease. For instance, these diet-related metabolites can be used to monitor and reduce the risk of immune response, diabetes, or cardiovascular diseases. Given the interest in these metabolites, different targeted metabolomic methods based on UP ...
... Thyroid hormones and their derivatives are structurally related to the non-essential amino acid tyrosine (4-hydroxyphenylalanine). However, there are physicochemical differences that make it difficult to apply an analytical method for their simultaneous detection. This work focused on the optimization of a method using liquid chromatography-electrospray ionization mass spectrometry to measure eigh ...
... A variety of vitamin E dietary supplement capsules (DSC) based on different natural oils or synthesis products are currently found on the market whose vitamin contents need to be controlled before and after marketing. Here, we present an instrumental thin-layer chromatography (TLC) method which allows a direct determination of all tocopherols (T) and tocotrienols (T3) as well as α-tocopherol aceta ...
... In the present work, a new sensitive and selective high-performance liquid chromatography-fluorimetric detection (HPLC-FLD) method was developed and validated to quantify febuxostat (FBX) and montelukast (MON) in human plasma. The developed procedure was successfully applied to a study aimed at evaluating the pharmacokinetic profiles of febuxostat and montelukast in human plasma. A sol-gel poly (c ...
Codex Alimentarius; acetic acid; acetonitrile; agriculture; benzoic acid; chemical species; corn; half life; harvest date; isoxaflutole; mass spectrometry; maximum residue limits; metabolites; secondary amines; soot; sorbents; ultra-performance liquid chromatography; China
Abstract:
... OBJECTIVE: An improved QuEChERS method was established and verified for simultaneous determination of isoxaflutole and its metabolites diketonitrile and benzoic acid analogue residues in corn and plants. This method was mainly used to study the digestion rule and final residue level of isoxaflutole and its metabolites in corn and plants. It was hoped that the safe use of isoxaflutole in corn can b ...
European Union; acetic acid; capillary electrophoresis; chemical species; diodes; electrolytes; low fat milk; maximum residue limits; methanol; pH; sodium citrate; yogurt
Abstract:
... A dynamic pH junction was used in capillary electrophoresis (CE-DAD) to on-line preconcentrate, separate, and determine trace amounts of sulfonamide antibiotics (SAs) in milk and yoghurt samples in this study. A sample matrix with 0.15% acetic acid and 10% methanol (MeOH) at a pH of 4.0, and a background electrolyte (BGE) that contained 35 mM sodium citrate with 10% MeOH at a pH of 8.5, and an aci ...
Japan; Oriental traditional medicine; acetic acid; acetonitrile; blood-brain barrier; brain; chemical species; chemistry; drugs; electrospray ionization mass spectrometry; heart; kaempferol; kidneys; liver; lungs; methanol; naringenin; naringin; oral administration; osteoporosis; quality control; quercetin; rhizomes; small intestine; spleen; stomach; tissue distribution; uterus; China; Korean Peninsula
Abstract:
... Drynariae Rhizoma (Kunze ex Mett.) J. Sm. has been extensively used in China, Japan, and Korea to treat osteoporosis and tonify kidneys. A rapid and validated UPLC-MS/MS method for simultaneous determination of the seven analytes including neoeriocitrin, luteolin-7-O-β-D-glucoside, astragalin, naringin, eriodictyol, naringenin, and kaempferol in rats’ various tissues (heart, liver, spleen, lung, k ...
acetic acid; acetonitrile; chemical species; liquid chromatography; sediments; sulfates; sulfonates; tandem mass spectrometry; ultrasonic treatment; ultrasonics
Abstract:
... Despite their very wide use in various fields, knowledge concerning surfactants in environmental solid matrices is generally poor. One of the difficulties encountered in the analysis of surfactants is their very diverse physicochemical properties which require different extraction techniques. The objective of this work was therefore to develop an extraction method in sediments that allows the simu ...
acetic acid; adsorption; chemical species; compliance; insecticides; protocols; rice; solvents; tandem mass spectrometry; Vietnam
Abstract:
... The emerging ungovernable application of pesticides in rice farming has attracted public concerns as these hazardous chemicals leave long-lasting environmental impacts and cause severe health effects. Here, an optimized analytical method was proposed for the measurement of 656 pesticide residues in rice samples collected in Vietnam. We utilized chromatography with tandem mass spectrometry systems ...
... In this work, a novel strategy to prepare molecularly imprinted polymers (MIPs) functionalized magnetic carbon nanotubes (MCNTs) via a facile sol-gel polymerization by adopting Cu²⁺-mediating interaction was presented for selective recognition of celastrol (Cel), in the traditional Chinese medicines (TCM). Firstly, template Cel, 3-aminopropyltriethoxysilane (APTES) as monomer and Cu²⁺ (co-monomer) ...
... Insulin-like growth factors 1 and 2 (IGF-1 and IGF-2) are important biomarkers in research and diagnosis of growth disorders. Quantitative analysis is performed using various ligand-binding assays or enzymatic digestion LC-MS/MS methods, whose widespread adoption is hampered by time-consuming sample preparation procedures. We present a simple and fast antibody-free LC-MS/MS method for the quantifi ...
acetic acid; adverse effects; ammonium acetate; bronchodilators; chemical species; clenbuterol; enzymatic hydrolysis; isoxsuprine; liver; lungs; methanol; muscle tissues; muscles; oxygen; pH; protein synthesis; ractopamine; solid phase extraction; tandem mass spectrometry; therapeutics; urine; veterinary medicine; zilpaterol hydrochloride
Abstract:
... Wide use is made of β-agonists in therapy due to their smooth muscle–relaxant properties. They also have a side effect of increasing muscle mass. Besides improving oxygen utilisation as bronchodilators, β-agonists increase protein synthesis and promote fat burning. The growth- and performance-enhancing effects are often exploited in illegal use. The guiding objective of this study was to develop a ...
acetic acid; arginine; capillary electrophoresis; chemical species; diagnostic techniques; interferometry; metabolic diseases; pH; refractive index
Abstract:
... High speed capillary electrophoresis (HSCE) combined with refractive index (RI) detection is developed for the rapid separation and detection of inorganic ions and amino acids. A mixture of three inorganic ions (K⁺, Na⁺, Li⁺) and eight amino acids (Lys, Arg, Ala, Gly, Val, Thr, Trp, Asp) are detected using back scatter interferometry (BSI), without the need for chemical modifications or contrast. ...
acetic acid; acetonitrile; antidepressants; chemical species; detection; electric field; electrolytes; extraction; liquid chromatography; liquid membranes; mass spectrometry; precision; screening; solvents; standard deviation; toxicity testing
Abstract:
... In this work, for the first time, chromatographic paper was used for a multiphase extraction assisted by an electric field (MPEF) and directly coupled to paper spray mass spectrometry (PS-MS). Using this approach, five tricyclic antidepressants (TCAs) were determined in oral fluid. Firstly, the MPEF conditions were optimized using liquid chromatography-mass spectrometry (LC-MS/MS). The effects of ...
... The molecularly imprinted polymers (MIPs) with the following herbicides used as templates 2,4-dichlorophenoxyacetic acid (2,4-D) or 4-chloro-2-methylphenoxy- acetic acid (MCPA) were synthesized by precipitation polymerization technique using 4-vinylpyridine (4-VP) as a functional monomer, ethylene glycol dimethacrylate (EGDMA) as a cross-linking agent, and 2,2′-azobisisobutyronitrile (AIBN) as an ...
acetic acid; alanine; capillary electrophoresis; chemical species; chromatography; liquids; mass spectrometry; metabolomics; methionine; pH; sprayers; tyrosine; valine
Abstract:
... The performance of an original CE-MS interface that allows the in-axis positioning of the electrospray with respect to the MS inlet was evaluated. The variations in the geometrical alignment of this configuration in the absence of a nebulizing gas afforded a significant reduction in the sheath-liquid flow rate from 3 µL/min to as low as 300 nL/min. The sheath liquid and BGE were respectively compo ...
Mentha pulegium; acetic acid; chemical species; dibutyl phthalate; green tea; high performance liquid chromatography; lemons; liquid-phase microextraction; mint; phthalic acid; solidification; solvents; standard deviation
Abstract:
... In this work, a natural deep eutectic solvent (NADES) consisting of L-menthol and acetic acid in a 1:1 molar ratio has been applied as extraction solvent for the dispersive liquid-liquid microextraction based on the solidification of the floating organic drop (DLLME-SFO) of a group of nine phthalic acid esters (dipropyl phthalate, DPP; butyl benzyl phthalate, BBP; dibutyl phthalate, DBP; dicyclohe ...
... Surface-enhanced Raman scattering (SERS) has been a useful sensing technique, in which inelastic light scattering can be significantly enhanced by absorbing molecules onto rough metal surfaces or nanoparticles. Although many methods have been developed to prepare SERS substrates, it is still highly desirable and challenging to design SERS substrates, especially with highly ordered and controlled t ...
acetic acid; acetonitrile; acrylamides; anticonvulsants; area; blood serum; chemical bonding; chemical species; chlorides; composite polymers; electric potential difference; electroosmosis; electrophoresis; flow; humans; length; precision; separation; silica; volume; zwitterions
Abstract:
... Electrophoretic stacking is developed for sensitive determination of three zwitterionic antiepileptics, namely vigabatrin, pregabalin and gabapentin, in human serum. CE separation is performed in a 25 μm fused silica capillary covalently coated with the copolymer of acrylamide with 5% content of permanently charged 3-acrylamidopropyl trimethylammonium chloride (PAMAPTAC). In background electrolyte ...
acetic acid; adsorbents; chemical species; ciprofloxacin; coordination polymers; detection limit; high performance liquid chromatography; magnetic materials; magnetism; microchip technology; milk; norfloxacin; ofloxacin; sampling; solid phase extraction; solvents; surface area; tandem mass spectrometry; toxicity; zinc
Abstract:
... Herein, a two dimensional metal-organic framework (2D MOF) is introduced as an efficient adsorbent for simultaneously extraction of fluoroquinolones (FQs) from milk samples. The proposed MOF was synthesized by solvothermal method. The high surface area and high accessible sites of prepared MOF offered a unique adsorbent for solid phase extraction (SPE). The experiments showed the great ability of ...
acetic acid; acetonitrile; beers; centrifugation; chemical species; food chemistry; homogenization; laws and regulations; malt; mycotoxins; pesticides; spent grains; tandem mass spectrometry; uncertainty
Abstract:
... A multiclass analytical method to determine pesticides and mycotoxins in beer-related matrices based on the dilute and shoot approach was optimized and validated according to the European guidelines SANTE/12682/2019 and EC/401/2006. Extraction used acidified acetonitrile at 1% (v/v) acetic acid, followed by horizontal shaking homogenization, centrifugation, freeze-out step for cleanup, another cen ...
Alan Nascimento Bernardes; Leandro Augusto Gouvêa Godoi; Priscila Rosseto Camiloti; Absai da Conceição Gomes; Bruna Larissa Sandy Sanchez; Ana Paula Rodrigues Torres; Lívia Silva Botta
... The composition of sugarcane vinasse varies according to the substrate of alcoholic fermentation, e.g. if it is sugarcane juice and/or molasses. Regardless of the origin, the main organic compounds found in sugarcane vinasse are organic acids, alcohols and a low amount of carbohydrates. To access the organic composition of such wastewater, the present paper describes a high-performance liquid chro ...
Oriental traditional medicine; acetic acid; acetonitrile; aerosols; aqueous solutions; chemical species; drugs; high performance liquid chromatography; markets; quality control; quantitative analysis; China
Abstract:
... Bupleuri Radix (Chaihu, in Chinese) is the principal drug in Xiaochaihu granules (XGs) that is a famous Chinese medicine preparation in China. Since previous analytical methods have not focused on the multiactive saikosaponins of Chaihu, it is difficult to effectively control the quality of XG on the market. In this manuscript, the simultaneous determination of 7 saikosaponins (saikosaponins C, I, ...
... For many foods that undergo thermal treatment, the generation of numerous process-induced compounds has strong implications for food quality and safety. Today, increasing attention is payed to the generation and occurrence of particular classes of newly formed compounds in processed foods for their potential health implication. It is therefore of the utmost importance to monitor the process with f ...
Japan; Mizuhopecten; Ruditapes philippinarum; acetic acid; chemical species; clams; detection limit; gonyautoxins; graphene; hydrophilic interaction chromatography; neurotoxins; saxitoxins; scallops; shellfish; solid phase extraction; tandem mass spectrometry; tetrodotoxin; Europe; New Zealand
Abstract:
... Paralytic shellfish toxins and tetrodotoxin (puffer-fish toxin), the latter of which was recently found in bivalves from Europe, Japan, and New Zealand, are potent neurotoxins. A simple and effective clean-up procedure was developed for the simultaneous determination of ten paralytic shellfish toxins (gonyautoxins 1–6, decarbamoylgonyautoxins 2 and 3, and N-sulfocarbamoylgonyautoxins 2 and 3) and ...
... A rapid and sensitive UPLC-MS/MS method was developed and fully validated for the quantification of hyperoside in rat plasma after intragastric, intraperitoneal and intravenous administration. Geniposide was used as an internal standard, and simple liquid–liquid extraction by ethyl acetate was utilized for to extracting the analytes from the rat plasma samples. Chromatographic separation was carri ...
... A poly (N-isopropyl acrylamide) (polyNIPA)-based hybrid column for capillary liquid chromatography (cLC) was prepared with N-isopropyl acrylamide (NIPA) and alkoxysilanes through a sol–gel “one-pot” method. In this process, the hydrolyzed tetramethoxysilane (TMOS) and vinyltrimethoxysilane (VTMS) were the precursors for the synthesis of a silica-based monolith and subsequently reacted with organic ...
... A method for the simultaneous quantification of B vitamins and related amines in one-carbon (1C) metabolism would benefit the study of diet and genetic/epigenetic regulation of mammalian development and health. We present a validated method for the simultaneous quantitative analysis of 13 B vitamers and four related 1C-pathway amine intermediates in liver using hydrophilic interaction chromatograp ...
Helianthus annuus; Salvia hispanica; acetic acid; acetonitrile; chemical species; commercialization; detection limit; dietary supplements; guidelines; laws and regulations; liquid chromatography; maximum residue limits; methanol; pesticide residues; pumpkins; seeds; standard deviation; sulfonylureas; tandem mass spectrometry; temperature
Abstract:
... This work proposes a novel Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) method in combination with ultra-high performance liquid chromatography-tandem mass spectrometry for the determination of sulfonylurea residues in edible seeds. The chromatographic separation of nine sulfonylureas was accomplished in less than 5.5 min, using a Luna Omega C₁₈ column (50 × 2.1 mm, 1.6 µm). Mobile p ...
... Short-chain fatty acids (SCFAs) are gut microbiota metabolites recognized for their beneficial effects on the host organism. In this study, a simple and rapid sample preparation method combined to SCFAs analysis by direct injection and gas chromatography coupled with flame ionization detection (GC-FID), for the determination and quantification of eight SCFAs (acetic, propionic, i-butyric, butyric, ...
acesulfame potassium; acetic acid; analytical chemistry; capillary electrophoresis; chemical species; disinfection; electrolytes; environmental assessment; isopropyl alcohol; liquids; mass spectrometry; perfluorooctane sulfonic acid; phosphates; pollutants; reversed-phase liquid chromatography; silica; spectrometers; standard deviation; sulfates; water analysis
Abstract:
... Reversed-phase liquid chromatography (RPLC) used for water analysis is not ideal for the analysis of highly polar and ionic contaminants because of low retention. Capillary electrophoresis (CE), on the other hand, is perfectly suited for the separation of ionic compounds but rarely applied in environmental analysis due to the weak concentration sensitivity when coupled to mass spectrometry (MS). H ...
acetic acid; acidity; agitation; apple juice; beverages; biodegradability; centrifugation; chemical species; chromatography; dibutyl phthalate; differential scanning calorimetry; droplets; hydrochloric acid; infrared spectroscopy; liquid-phase microextraction; mineral water; solubilization; solvents; standard deviation; tap water; toxicity
Abstract:
... In this work, a natural deep eutectic solvent (NADES) composed of l-menthol:acetic acid 1:1 (molar ratio) was applied for the first time as the extraction solvent for the dispersive liquid–liquid microextraction (DLLME) of a group of 9 phthalic acid esters (i.e., dipropyl phthalate, DPP; butyl benzyl phthalate, BBP; dibutyl phthalate, DBP; diisopentyl phthalate, DIPP; di-n-pentyl phthalate, DNPP; ...
... Lipid A represents a heterogeneous group of bacterial outer membrane phosphoglycolipids, which play a major role in the pathogenesis of Gram‐negative sepsis. The number and position of phosphoryl and acyl groups in lipid A molecules are key structural determinants in their bioactivities. In this study, a NACE–ESI‐MS/MS method was developed for the simultaneous analysis of lipid A isomers possessin ...
... In the present study, liquid chromatography coupled to an Orbitrap mass spectrometer (HPLC–Q-Orbitrap MS) was used as an approach for identification and quantification of 113 drugs simultaneously in biological samples (whole blood/plasma/serum). Samples were prepared using liquid–liquid extraction conducted using a trizma/isopropanol/butyl chloride buffer system. Reversed-phase separation employin ...
acetates; acetic acid; acetonitrile; ammonia; chemical species; dialysis; enantiomers; enantioselectivity; humans; isotope labeling; lansoprazole; liquid chromatography; proton pump; proton pump inhibitors; separation; spectrometers; tandem mass spectrometry
Abstract:
... Proton pump inhibitors, including omeprazole, rabeprazole, lansoprazole, and pantoprazole, achieved simultaneous enantioselective determination in the human plasma by chiral liquid chromatography–tandem mass spectrometry. The four corresponding stable isotope‐labeled proton pump inhibitors were adopted as the internal standards. Each enantiomer and the internal standards were extracted with aceton ...
Shun-Chung Yang; Lisa Welter; Anand Kolatkar; Jorge Nieva; Kathryn R. Waitman; Kuo-Fang Huang; Wen-Hsuan Liao; Shotaro Takano; William M. Berelson; A. Joshua West; Peter Kuhn; Seth G. John
... The isotopic composition of iron, zinc, copper, and cadmium (δ⁵⁶Fe, δ⁶⁶Zn, δ⁶⁵Cu, and δ¹¹⁴Cd) are novel and promising tools to study the metabolism and homeostasis of trace metals in the human body. Serum δ⁶⁵Cu has been proposed as a potential tool for diagnosis of cancer in liquid biopsy, and other metals may have similar utility. However, accurate analysis of trace metal isotopes is challenging ...
... Stomach content is a matrix often applied in post-mortem cases. It is especially important in oral intoxication cases. The main advantages are the usually high concentration of analytes and the lack of biotransformation process. Still, even with extensive sample preparation, the final extract is not always suitable for analysis. The aim of this study was to develop an alternative method using QuEC ...
acetic acid; chemical species; comprehensive two-dimensional gas chromatography; containers; databases; ethanol; iso-octanes; manufacturing; mass spectrometry; polypropylenes; volatile compounds
Abstract:
... This study reports on the potential of comprehensive two-dimensional gas chromatography combined with time-of-flight mass spectrometry (GC×GC−ToF MS) for the exhaustive untargeted characterization of the volatile and semi-volatile analytes migrating from four commercial polypropylene food containers into four simulants (water, 3% acetic acid, 10% ethanol, and isooctane) according to European Regul ...
acetic acid; acetonitrile; adsorption; chemical species; desorption; detection limit; fabrics; filtration; high performance liquid chromatography; methanol; models; pH; solvents; standard deviation
Abstract:
... A new sample preparation and chromatographic separation method for methyl paraben (MP), propyl paraben (PP) and butyl paraben (BP) in cosmetic and environmental samples has been developed, based on fabric phase sorptive extraction (FPSE) and high performance liquid chromatography-photodiode array (HPLC-PDA) detection. In the proposed method, MP, PP and BP molecules were efficiently retained on a s ...
high performance liquid chromatography; oral administration; drugs; chemical species; oxyclozanide; standard deviation; half life; formates; monitoring; chlorine; cattle; models; acetonitrile; niclosamide; ammonium; pharmacokinetics; acetic acid; fascioliasis; methanol; tandem mass spectrometry; fluorine
Abstract:
... BACKGROUND: Oxyclozanide is an anthelmintic drug that is widely used to treat fasciolosis. However, the pharmacokinetics of oxyclozanide in cattle are not yet clearly understood. The present study was designed to develop a sensitive method to determine oxyclozanide levels in cattle plasma using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) and to study its pharmacoki ...
... A validated approach to determine various methionine cycle metabolites (S-adenosylmethionine, S-adenosylhomocysteine, and methylthioadenosine) in human blood plasma is offered. The approach is based on solid-phase extraction (with grafted phenylboronic acid) and derivatization with chloroacetaldehyde followed by ultra-performance liquid chromatography with fluorescence detection. We used a 100 × 2 ...
... A highly sensitive and specific methodology has been developed for the simultaneous determination of the flavonoids hesperidin, hesperetin, naringin, and naringenin in chicken plasma employing UHPLC-HRMS (Orbitrap Velos). Plasma samples were preprocessed by protein precipitation with cold acetone. Analysis was carried out on an INTERCHIM UHPLC C18 column using aq. 0.1% glacial acetic acid, acetoni ...
... In this study a method is developed for quantitative analysis of three potential biomarkers, including 4-hydroxyphenyl acetic acid (PHPAA), 4-hydroxyphenyl lactic acid (PHPLA) and 3,4-hydroxyphenylpropionic acid (PHPA), in human urine. Molecular imprinted polymers (MIPs) as the sample clean up materials were applied to selectively extract these tyrosine metabolites, followed by precise detection u ...
acetic acid; chemical species; cooking fats and oils; electrospray ionization mass spectrometry; formic acid; glufosinate; glyphosate; herbicide resistance; ionization; liquid chromatography; liquids; metabolites; methanol; tandem mass spectrometry
Abstract:
... A method has been developed for the rapid, specific, accurate, precise and sensitive determination of glufosinate, glyphosate and its major metabolite, aminomethylphosphonic acid, in edible oils, by liquid chromatography coupled to tandem mass spectrometry. Oils were extracted with acidified water (1% formic acid), and the extracts were directly injected into an LC using a Hypercarb column as the ...
... Ingestion of hypoglycin A (HGA) in maple seeds or alkaloids produced by symbiotic fungi in pasture grasses is thought to be associated with various syndromes in grazing animals. This article describes analytical methods for monitoring long-term exposure to HGA, its metabolite MCPA-carnitine, as well as ergocristine, ergocryptine, ergotamine, ergovaline, lolitrem B, N-acetylloline, N-formylloline, ...
... A method for simultaneous determination of Fe (232.036 nm) and Ni (232.195 nm) in vegetable oil samples by high-resolution continuum source graphite furnace atomic absorption spectrometry (HR-CS GF AAS) after an acid extraction of the analytes is proposed. In the extraction step, hydrochloric, nitric and acetic acid solutions were tested. The optimization of the procedure was performed by applying ...
... Barrier materials have wide applicability in both professional (military, medical, industrial) and non-professional (leisure and sports) fields. This paper focuses on the preparation of real conductive polymer (CP) sensors, for the study of the permeation of volatile toxic compounds through barrier materials. Use of such a CP sensor can help improve the quality of barrier materials used in protect ...
Sepiidae; acetic acid; acetonitrile; chemical species; detection limit; drug residues; malachite green; oysters; quinolones; scallops; squid; standard deviation; tandem mass spectrometry; tetracycline; ultra-performance liquid chromatography; veterinary drugs; China
Abstract:
... The extant methods for detecting multi-residues in aquatic products can avoid the disadvantages of complex pretreatment, long time consumption, single detection type, and low sensitivity. Therefore, developing a method that enables a multi-residue detection of veterinary drugs is very important. QuEChERS is a simple, rapid, and efficient method for detecting multi-drug residues. In this work, QuEC ...
acetic acid; acetonitrile; adsorbents; ammonium acetate; aromatic amines; baked goods; byproducts; chemical species; heat; heterocyclic compounds; liquid chromatography; monitoring; nitrogen; quantitative analysis; sodium hydroxide; standard deviation; tandem mass spectrometry
Abstract:
... Heterocyclic aromatic amines (HAAs) are harmful by-products naturally formed during the heating process of foodstuffs. The present work reported an analytical method for HAAs analysis for the first time in bakery products by QuEChERS technique combined with ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Bakery products were ultrasonically extracted with aceton ...
... The physicochemical treatment (PT) of slaughterhouse wastewater (SWW) was investigated. In the first stage, calcium acetate (Ca(Ac)₂) was synthesized in five different ways: (1) acetic acid (HAc) and chicken eggshell (CaAc1), (2) lime (CaAc2), (3) a 1:1 eggshell and lime mixture (CaAc3), (4) a 1:2 eggshell and lime mixture (CaAc4), and (5) calcium oxide via the calcination of eggshell (CaAc5). The ...
acetic acid; acetonitrile; ammonium acetate; calibration; carbon; chemical species; electrospray ionization mass spectrometry; guidelines; half life; humans; liquid chromatography; liquid-liquid extraction; metabolites; monitoring; oral administration; pharmacokinetics; stable isotopes; tandem mass spectrometry; yohimbine
Abstract:
... We developed and validated a human plasma LC-MS/MS assay according to FDA guidelines to determine the impact of the CYP2D6 inhibitor paroxetine on the pharmacokinetics of the assumed specific CYP2D6 substrate yohimbine. Yohimbine, its main metabolite 11-OH-yohimbine, and paroxetine were quantified using plasma (100 μL) and liquid–liquid extraction for sample preparation. Analytes were separated wi ...
Codex Alimentarius; European Union; acetic acid; acetonitrile; animal tissues; cation exchange; cattle; chemical species; cleaning; compliance; drug residues; ethanol; ethyl acetate; hexane; hydrogen peroxide; liquid chromatography; liver; maximum residue limits; metabolites; monitoring; muscles; oxidation; sodium hydroxide; solid phase extraction; tandem mass spectrometry; temperature; triclabendazole
Abstract:
... A reliable LC-MS/MS analytical method for the determination of residual triclabendazole and its principal metabolites (triclabendazole sulfoxide, triclabendazole sulfone and keto-triclabendazole) in bovine tissues was developed, in which triclabendazole and its metabolites are oxidized to keto-triclabendazole as a marker residue. The method involves sample digestion with hot sodium hydroxide, thus ...
acetic acid; acetonitrile; aquatic invertebrates; calibration; chemical species; computer software; drugs; energy; freshwater; ions; liquid chromatography; liquid-liquid extraction; personal care products; streams; tandem mass spectrometry
Abstract:
... A simple sample preparation method based on a modified liquid‐phase extraction approach to extract selected pharmaceuticals and personal care products from freshwater organisms is described. Extracted samples were analysed using liquid chromatography with Q‐Exactive plus hybrid quadrupole Orbitrap mass spectrometry, using 2.6 μm C18 media. A 0.1% v/v acetic acid/acetonitrile mobile phase was appli ...
... The supercritical water gasification of xylose, a model substrate for hemicellulose, was carried out at 400 and 450 °C and at a constant pressure of 25 MPa in the presence of acetic acid using a continuous flow reactor. More specifically, we aimed to compare the reaction rate constants of xylose decomposition in both the presence and absence of acetic acid. Upon the application of a residence time ...
acetic acid; acetonitrile; atropine; chemical species; corn; liquid chromatography; magnesium sulfate; methanol; scopolamine; sodium chloride; sodium citrate; tandem mass spectrometry
Abstract:
... The undemanding LC-MS/MS method was developed for the synchronized analysis of atropine and scopolamine in maize crop. The dSPE was carried out with 1% acetic acid in acetonitrile/water and a mixture of magnesium sulphate, sodium chloride and sodium citrate. The analytes were separated on a Zorbax XDB C18 column using methanol/water as the mobile phase in gradient mode. The detection was done usin ...
... We report a flexible sensor array electronic tongue system that is fabricated on a polymer substrate by the laser direct writing process for multiflavor detection. Electronic tongue is a sensing system that is applied to detect different elements with the same sensor array. By analyzing responses from different measurement units, it enables a cross-sensitivity, namely, the ability of the system to ...
acetic acid; acetonitrile; chemical species; ciprofloxacin; cleaning; data collection; databases; honey; liquid chromatography; macrolides; mass spectrometry; pH; screening; sorbents; sulfonamides; tetracyclines; veterinary drugs
Abstract:
... A strategy for the quantification and confirmation of 40 multi-class veterinary drugs in honey by QuEChERS (quick, easy, cheap, effective, rugged, and safe) combined with liquid chromatography coupled quadrupole time-of-flight mass spectrometry (LC-Q-TOF/MS) is described. The veterinary drugs examined belong to four classes: quinolones, sulfonamides, macrolides, and tetracyclines. Before analysis ...
Bauhinia variegata; Cecropia palmata; Connarus; Mansoa alliacea; acetic acid; acetonitrile; apigenin; caffeic acid; catechin; chemical species; chlorogenic acid; data collection; detection limit; ferulic acid; high performance liquid chromatography; medicinal plants; monitoring; p-coumaric acid; rutin; tandem mass spectrometry; ultra-performance liquid chromatography; vanillic acid; Amazonia; Brazil
Abstract:
... A method for the separation, identification and quantification of 24 phenolic compounds using ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) was developed and validated. Six species of traditional medicinal plants from the Brazilian Amazon region were studied (Mansoa alliacea, Bauhinia variegata var. variegata, Bauhinia variegata var. alboflava, Conn ...
acetic acid; acetonitrile; adsorbents; bisphenol A; chemical species; detection limit; liquid chromatography; solid phase extraction; tandem mass spectrometry; tea
Abstract:
... A rapid and sensitive method for the simultaneous determination of bisphenol A (BPA) and tetrabromobisphenol A (TBBPA) in tea using liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed and validated. Sample preparation was based on a modified QuEChERS procedure through extraction of the target analytes using acetonitrile with 0.7% acetic acid followed by a dispersive solid phase ...
acetic acid; acetonitrile; centrifugation; chemical species; dissolved carbon dioxide; emulsifying; gas chromatography; glass; liquid-phase microextraction; mass spectrometry; pyrethrins; separation; sodium bicarbonate; solvents
Abstract:
... A method using dissolved carbon dioxide flotation after dispersive liquid–liquid microextraction (DCF-DLLME) was proposed for the determination of sixteen pyrethroids in water samples, coupled with gas chromatography with triple quadrupole mass spectrometry in a homemade glass round flask. The DCF-DLLME method is based on the rapid and simple phase separation of a low density organic solvent from ...
Callicarpa; acetic acid; acetonitrile; chemical species; cultivars; ethanol; flavanoids; glycosides; high performance liquid chromatography; quantitative analysis; solvents; tandem mass spectrometry; China
Abstract:
... An effective and comprehensive method was developed for the simultaneous analysis of phenylethanoid glycosides and flavanoid compounds in the ethanol extracts of Callicarpa kwangtungensis Chun (CK) using high-performance liquid chromatography-electrospray ionization-ion trap-time-of-flight-tandem mass spectrometry (HPLC-ESI-IT-TOF-MS/MS) and a high-performance liquid chromatography-diode array det ...
acetic acid; acetonitrile; chemical species; chemometrics; cluster analysis; high performance liquid chromatography; principal component analysis; quality control; quantitative analysis; quercetin; regression analysis; rutin; wavelengths; China
Abstract:
... A simple and efficient HPLC method is developed for the fingerprint analysis of Flos Sophorae Immaturus and for the simultaneous determination of three flavonoids in Flos Sophorae Immaturus, namely rutin, narcissin and quercetin. The separation of analytes is conducted on a Dikma Diamonsil C₁₈ column (250 mm × 4.6 mm, 5 μm) at 35 °C; the wavelength of UV detector was set at 254 nm; the mobile phas ...
... Sequential extraction consists of the use of a number of extractors with different chemical properties that are progressively applied to a sample. The objective of this study was to evaluate the influence of sequential extraction of Cu, Fe, Mn, Mg and Zn from fruit and vegetable residue flour during storage for up to 60 days. The following extractors were applied: 1M calcium chloride, 0.1M acetic ...
acetic acid; acetonitrile; benzimidazoles; beta-adrenergic agonists; chemical species; dried milk; elemental composition; hormones; ions; liquid chromatography; macrolides; nitroimidazoles; pH; quinolones; screening; sorbents; sulfonamides; tandem mass spectrometry; tetracyclines; tranquilizers; veterinary drugs
Abstract:
... In this study, a simple and rapid multi-residue screening method for the quantification and confirmation of 100 multi-class veterinary drugs in milk powder by the Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) method combined with liquid chromatography coupled to quadrupole time-of-flight mass spectrometry was developed. The veterinary drugs investigated belonged to several families su ...
acetic acid; acetonitrile; beef; benzimidazoles; beta-adrenergic agonists; chemical species; drug residues; electrospray ionization mass spectrometry; high performance liquid chromatography; macrolides; muscle tissues; ofloxacin; pork; sheep meat; sulfonamides; veterinary drugs
Abstract:
... A novel method for the determination of 55 multi-class veterinary drug residues in different muscle tissues (porcine, bovine and ovine animals) by modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) combined with high performance liquid chromatography coupled to electrospray ionization tandem mass spectrometry (HPLC-MS/MS) is described. The veterinary drugs focused on here belong to ...
... A sensitive, rapid and reliable ultra-performance liquid chromatography (UPLC) with Photo-Diode Array (PDA) detection method was developed for simultaneous determination of sulindac and its metabolites sulindac sulfide and sulindac sulfone in human plasma. The analytes were extracted by dichloromethane from human plasma using a liquid–liquid extraction method. The chromatographic separation was pe ...
... Torrefied biomass provides opportunities for an alternative, renewable fuel in the energy market. Much work on torrefaction is based on weight loss transients without much insight into the evolution of volatile species. A previous model from our group has been developed that predicts the degradation of raw biomass into specific chemical species during torrefaction (water, acetic acid, carbon monox ...
acetic acid; aqueous solutions; capillary zone electrophoresis; chemical species; detectors; electrolytes; enzymes; high performance liquid chromatography
Abstract:
... A method based on capillary electrophoresis with capacitively coupled contactless conductivity detection (CE-C⁴D) for determination of two important phosphodiesterase type-5 inhibitors (sildenafil and vardenafil) is introduced. The background electrolyte (BGE) consisted of an aqueous solution of 500 mmol L⁻¹ acetic acid, and the capillary was previously treated with polybrene solution to prevent c ...
Rauvolfia; acetic acid; ammonium acetate; berberine; capillary electrophoresis; chemical species; electric potential difference; methanol; reserpine; yohimbine
Abstract:
... In this article, we propose very simple procedures to analyze two important indole alkaloids, reserpine and yohimbine, in Rauvolfia yunnanensis. A nonaqueous CE method has been employed using berberine as an internal standard. Optimum separation conditions were obtained when the sample was injected by pressure for 3 s at 50 mbar and then separated with the buffer containing 40 mM ammonium acetate, ...
Aloe vera; acetic acid; acetonitrile; centrifugation; chemical species; emodin; filtration; gels; ionization; methanol; particle size; tandem mass spectrometry; ultra-performance liquid chromatography
Abstract:
... A novel method for the simultaneous determination of aloin A and aloe emodin in products labeled to contain Aloe vera has been developed and validated. This analytical procedure involved extracting a test portion of the product in acetonitrile : water (40 : 60, v/v), followed by centrifugation and filtration through a 0.2 μm PTFE filter. Quantitation was achieved using ultra-performance liquid chr ...