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Liquid Liquid extraction

Francesca Freni, Sara Bianco, Claudia Vignali, Angelo Groppi, Matteo Moretti, Antonio Marco Maria Osculati, Luca Morini
A multi-analyte method for detection and quantification of 16 synthetic cathinones (known also as "bath salts") in human hair has been developed and fully validated using liquid chromatography-tandem mass spectrometry system. About 20 mg of hair samples, previously washed and homogenized, were ultrasonicated with 1 mL HCl 0.1 M solution. Samples were then extracted using a solid phase extraction procedure (SPE), taken to dryness and reconstituted in 100 μL mobile phase. Finally, they were directly injected into a liquid chromatographic system, coupled with tandem mass spectrometer detector...
February 28, 2019: Forensic Science International
Jiao Guan, Liming Wang, Jia Jin, Sheng Chang, Xiao Xiao, Bo Feng, Heyun Zhu
Huangqi Guizhi Wuwu Decoction (HGWWD), consisting of Radix Astragali, Cinnamomi Ramulus, Paeoniae Radix Alba, Zingiberis Rhizoma Recens and Jujubae Fructus, is a widely used Traditional Chinese Medicine (TCM) formula for the treatment of human blood impediment in China for nearly 2000 years. In order to make good and rational use of this formula in the future, a rapid, sensitive and robust ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed for simultaneous determination of calycosin-7-O-β-D-glucoside, cinnamic acid, paeoniflorin and albiflorin, the main active constituents of HGWWD, in rat plasma using geniposide as internal standard (IS)...
March 14, 2019: Journal of Pharmaceutical and Biomedical Analysis
Benjamin Rioux, Jacques Rouanet, Hussein Akil, Sophie Besse, Eric Debiton, Bernadette Bouchon, Françoise Degoul, Mercedes Quintana
Determination of eumelanin and pheomelanin in melanomas that exhibit different pigmentation was carried using a solid-phase extraction (SPE) preparation method based on weak anion exchange chemistry. This extraction significantly enhanced the chromatographic profile obtained by reverse phase high performance liquid chromatography-diode array detection (RP-HPLC-DAD). The SPE method was developed using aqueous standards of melanin markers: thiazole-2,4,5-tricarboxylic acid (TTCA), thiazole-4,5-dicarboxylic acid (TDCA), pyrrole-2,3-dicarboxylic acid (PDCA) and pyrrole-2,3,5-tricarboxylic acid (PTCA) and non-pigmented cell lines spiked with those markers...
March 11, 2019: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
Rosa Montes, Rosario Rodil, Rafael Cela, Jose Benito Quintana
The presence of persistent and mobile organic contaminants (PMOC) in aquatic environments has become a matter of concern due to their ability of breaking through natural and anthropogenic barriers, even reaching drinking water. The presence of many of these compounds in surface and drinking water has been reported in screening studies, but there is still a lack of analytical methods capable of quantifying them. Herein, we propose a method combining mixed-mode-solid-phase extraction (MM-SPE) as pre-concentration technique and mixed-mode liquid chromatography (MMLC) coupled to tandem mass spectrometry as determination technique for the quantitative determination of 23 target PMOCs in surface and drinking water samples...
March 21, 2019: Analytical Chemistry
Clara Torrentó, Rani Bakkour, Gaétan Glauser, Aileen Melsbach, Violaine Ponsin, Thomas B Hofstetter, Martin Elsner, Daniel Hunkeler
Compound-specific isotope analysis (CSIA) is a valuable tool for assessing the fate of organic pollutants in the environment. However, the requirement of sufficient analyte mass for precise isotope ratio mass spectrometry combined with prevailing low environmental concentrations currently limits comprehensive applications to many micropollutants. Here, we evaluate the upscaling of solid-phase extraction (SPE) approaches for routine CSIA of herbicides. To cover a wide range of polarity, a SPE method with two sorbents (a hydrophobic hypercrosslinked sorbent and a hydrophilic sorbent) was developed...
March 21, 2019: Analyst
S D Liu, T Min, M Wang, D M Zhang
OBJECTIVES: To investigate the maximum allowable deviation of retention time (RT) or relative retention time (RRT) between the common poisons (drugs) and standard solvent by gas chromatography-mass spectrometry (GC-MS). METHODS: After pretreatment with liquid-liquid extraction, four common poisons (drugs)-dichlorvos, phorate, diazepam and estazolam-were detected by full scan mode GC-MS. RT and RRT were analyzed according to combined uncertainty and expanded uncertainty...
June 2018: Fa Yi Xue za Zhi
J X Zhai, H Yan, M Shen, B H Shen, W Liu
OBJECTIVES: To develop a liquid chromatography-tandem mass spectrometry (LC-MS/MS) analytical method for the determination of oleandrin in blood and liver tissues, which could be applied to the cases of death caused by oleander poisoning. METHODS: Blood or liver tissues underwent a liquid-liquid extraction (LLE) using ethyl acetate, and the extract was separated on an Agilent ZORBAX SB-C18 column and eluted with a gradient of acetonitrile and 20 mmol/L ammonium acetate (containing 0...
June 2018: Fa Yi Xue za Zhi
Tibor Béres, Lucie Černochová, Sanja Ćavar Zeljković, Sandra Benická, Tomáš Gucký, Michal Berčák, Petr Tarkowski
This study compares alternative approaches for analyzing phytocannabinoids in different plant materials. Three chromatographic analytical methods (ultra-high-performance liquid chromatography with tandem mass spectrometric detection and gas chromatography with mass spectrometric and flame ionization detection) were evaluated regarding selectivity, sensitivity, analytical accuracy, and precision. The performance of the methods was compared and all three methods were demonstrated to be appropriate tools for analyzing phytocannabinoids in cannabis...
March 20, 2019: Analytical and Bioanalytical Chemistry
Zhen Li, Yang Li, Jin Li, Rui Liu, Jia Hao, Jun He, Yan-Xu Chang
A sensitive and simple liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated to simultaneously determine the toxic and other active components including isovanillin, scopoletin, periplocin, periplogenin, and periplocymarin after oral administration of cortex periplocae extract to rats. Plasma samples were prepared by protein precipitation with methanol. All compounds were separated on a C18 column with gradient elution using acetonitrile and formic acid aqueous solution (0...
2019: International Journal of Analytical Chemistry
Marianne Lauwers, Siegrid De Baere, Ben Letor, Michael Rychlik, Siska Croubels, Mathias Devreese
A reliable and practical multi-method was developed for the quantification of mycotoxins in plasma, urine, and feces of pigs, and plasma and excreta of broiler chickens using liquid chromatography⁻tandem mass spectrometry. The targeted mycotoxins belong to the regulated groups, i.e., aflatoxins, ochratoxin A and Fusarium mycotoxins, and to two groups of emerging mycotoxins, i.e., Alternaria mycotoxins and enniatins. In addition, the developed method was transferred to a LC-high resolution mass spectrometry instrument to qualitatively determine phase I and II metabolites, for which analytical standards are not always commercially available...
March 19, 2019: Toxins
Sina Taghvaee, Amirhosein Mousavi, Mohammad H Sowlat, Constantinos Sioutas
In this study, we developed a novel method for generating aerosols that are representative of real-world ambient particulate matter (PM) in terms of both physical and chemical characteristics, with the ultimate objective of using them for inhalation exposure studies. The protocol included collection of ambient PM on filters using a high-volume sampler, which were then extracted with ultrapure Milli-Q water using vortexing and sonication. As an alternative approach for collection, ambient particles were directly captured into aqueous slurry samples using the versatile aerosol concentration enrichment system (VACES)/aerosol-into-liquid collector tandem technology...
May 15, 2019: Science of the Total Environment
Matthew Wai Kin Wong, Nady Braidy, Russell Pickford, Fatemeh Vafaee, John Crawford, Julia Muenchhoff, Peter Schofield, John Attia, Henry Brodaty, Perminder Sachdev, Anne Poljak
Recent advances in mass spectrometry-based techniques have inspired research into lipidomics, a subfield of '-omics', which aims to identify and quantify large numbers of lipids in biological extracts. Although lipidomics is becoming increasingly popular as a screening tool for understanding disease mechanisms, it is largely unknown how the lipidome naturally varies by age and sex in healthy individuals. We aimed to identify cross-sectional associations of the human lipidome with 'physiological' ageing, using plasma from 100 subjects with an apolipoprotein E (APOE) E3/E3 genotype, and aged between 56 to 100 years...
2019: PloS One
Ansgar Korf, Viola Jeck, Robin Schmid, Patrick Olaf Helmer, Heiko Hayen
In recent years, proprietary and open-source bioinformatics software tools have been developed for the identification of lipids in complex biological samples based on high-resolution mass spectrometry data. These existent software tools often rely on publicly available lipid databases, such as LIPID MAPS®, which, in some cases, do only contain a limited number of lipid species for a specific lipid class. Other software solutions implement their own lipid species databases, which are often confined regarding implemented lipid classes, such as phospholipids...
March 20, 2019: Analytical Chemistry
Mi-Youn Brusniak, Chad Christianson, Emily Witthuhn, Shane Needham, James M Olson
AIM: Develop a universal extraction and liquid chromatography-mass spectrometer method to simultaneously analyze cystine-dense peptide (CDP) miniproteins from rat and human plasma. The results of the analysis will be used to assist selection of therapeutic drug candidates from the vast CDP library. METHODS & RESULTS: A micro-elution solid-phase extraction method was developed for the sample preparation of the CDP peptides in rat and human plasma followed by analysis by microflow liquid chromatography MS/MS...
March 20, 2019: Bioanalysis
Iria González-Mariño, Andrea Estevez-Danta, Rosario Rodil, Katyeny Manuela Da Silva, Fernando Fabriz Sodré, Rafael Cela, José Benito Quintana
This work provides a new analytical method for the determination of cocaine, its metabolites benzoylecgonine and cocaethylene, the pyrolytic products anhydroecgonine and anhydroecgonine methyl ester and the pharmaceutical levamisole in wastewater. Samples were solid-phase extracted and extracts analyzed by liquid chromatography-tandem mass spectrometry using, for the first time in the illicit drug field, a stationary phase that combines reversed-phase and weak cation-exchange functionalities. The overall method performance was satisfactory, with limits of detection below 1 ng/L, relative standard deviations below 21% and percentages of recovery between 93% and 121%...
March 19, 2019: Drug Testing and Analysis
Michael McCullagh, Cintia Alessandra Matiucci Pereira, Janete Harumi Yariwake
INTRODUCTION: Plant medicine/herbal extracts are typically complex, encompassing a wide range of flavonoid diversity and biological benefits. Combined with a lack of standards; species authentication profiling is a challenge. A non-targeted screening strategy using two-dimensional (2D) separation and specificity of ultra-high-performance liquid chromatography ion mobility collision-induced dissociation mass spectrometry (UHPLC-IM-CID-MS) has been investigated, to identify the 6-C and 8-C-glycosylflavone isomer orientin/isoorientin and vitexin/isovitexin pairs in Passiflora species...
March 19, 2019: Phytochemical Analysis: PCA
E L Legacki, E L Scholtz, B A Ball, A Esteller-Vico, S D Stanley, A J Conley
BACKGROUND: Few studies have provided a longitudinal analysis of systemic concentrations of conjugated oestrogens (and androgens) throughout pregnancy in mares, and those only using immuno-assay. The use of liquid chromatography tandem mass spectrometry (LC-MS/MS) will provide more accurate concentrations of circulating conjugated steroids. OBJECTIVES: To characterise circulating concentrations of individual conjugated steroids throughout equine gestation by using LC-MS/MS...
March 20, 2019: Equine Veterinary Journal
Shahlizah Sahul Hamid, Masataka Wakayama, Kensuke Ichihara, Katsutoshi Sakurai, Yujin Ashino, Rie Kadowaki, Tomoyoshi Soga, Masaru Tomita
Among seaweed groups, brown algae had characteristically high concentrations of mannitol, and green algae were characterised by fructose. In red algae, metabolite profiles of individual species should be evaluated. Seaweeds are metabolically different from terrestrial plants. However, general metabolite profiles of the three major seaweed groups, the brown, red, and green algae, and the effect of various extraction methods on metabolite profiling results have not been comprehensively explored. In this study, we evaluated the water-soluble metabolites in four brown, five red, and two green algae species collected from two sites in northern Japan, located in the Sea of Japan and the Pacific Ocean...
March 19, 2019: Planta
Igor A Butovich, Anne McMahon, Jadwiga C Wojtowicz, Nita Bhat, Amber Wilkerson
The possible role of sex in the biosynthesis of lipids in the Meibomian glands (termed meibogenesis) remains unclear. To determine if there were any major sex-specific differences in the lipid composition of meibomian gland secretions (meibum) and gene expression patterns (GEP) related to meibogenesis, we conducted a study using healthy, age and diet-matched young adult wild-type C57Bl/6J mice (2-2.5 month old). Tarsal plates (TP) were surgically excised from the eyelids of mice 2and subjected to transcriptomic and lipidomic analyses...
March 16, 2019: Ocular Surface
Pablo Dualde, Olga Pardo, Sandra F Fernández, Agustín Pastor, Vicent Yusà
For the first time, a multiresidue, sensitive and high throughput method for determination of bisphenol A, F and S and 4 parabens (methyl paraben, ethyl paraben, propyl paraben and butyl paraben) in human breast milk was developed. The proposed method includes an extraction and clean-up procedure based on QuEChERS methodology followed by liquid chromatography coupled to triple quadrupole mass spectrometry determination. Negative atmospheric pressure chemical ionization in the selected reaction monitoring mode was used for mass detection...
March 7, 2019: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
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