Read by QxMD icon Read

Solid phase extraction

Priyanka A Shah, Pranav S Shrivastav, Jaivik V Shah, Archana George
A single LC-MS/MS assay is developed and validated for simultaneous determination of metformin and dapagliflozin in human plasma using ion-pair solid phase extraction. Chromatographic separation of the analytes and their internal standards was carried out on a reversed-phase ACE 5CN (150 × 4.6 mm, 5 μm) column using acetonitrile-15 mM ammonium acetate, pH 4.5 (70:30, v/v) as the mobile phase. To achieve higher sensitivity and selectivity for the analytes, mass spectrometric analysis was performed using polarity switching approach...
December 5, 2018: Biomedical Chromatography: BMC
Girish Choppala, Edward D Burton
Schwertmannite is an Fe(III)-oxyhydroxysulfate which is common in acid mine drainage (AMD) and acid sulfate soil (ASS) environments. Natural schwertmannite is often enriched in Cr(III), yet the effects of Cr(III) substitution on schwertmannite transformation to more stable Fe(III) minerals has not been addressed. Here we examine, for the first time, the effects of Cr(III) substitution on the Fe(II)-accelerated transformation of schwertmannite. X-ray diffraction (XRD) and Fe K-edge extended X-ray absorption fine structure (EXAFS) spectroscopy shows that Cr(III) substitution inhibits schwertmannite transformation...
2018: PloS One
Kang Chen, Jie Wang, Shiyan Li, Yang Wang, Yiqi Zhang, Qing Shen
Tetracyclines abuse is frequently occurred in aquaculture against bacteria, rickettsiae, spirochetes and mycoplasmas. In this study, a high-throughput sample preparation method was developed using 96-well plate solid-phase extraction (p-SPE) and the extract was anal. yzed by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). The experimental conditions were optimized such that the pH is 4, the eluting solvent is methanol (2 mL), and the sorbent is hydrophilic-lipophilic balance (HLB) microsphere...
December 4, 2018: Electrophoresis
Tianli Yang, Ren He, Guihua Nie, Wenlei Wang, Gui Zhang, Yunchu Hu, Lichao Wu
In this work, carbon quantum dots were first prepared through one-pot hydrothermal route of the propyl aldehyde and sodium hydroxide via an aldol condensation reaction, and a novel solid-phase extraction adsorbent of hollow calcite single crystals was prepared via the precipitation of metal nitrates by the CO2 diffusion method in the presence of CQDs and further applied for excessive Cd(II) ions removal from water. The spectra and morphologies of the etched calcite were investigated by X-ray diffraction, Fourier transform infrared spectrometry, Scanning electron microscope, and Transmission electron microscopy...
December 4, 2018: Scientific Reports
Carsten Schmelter, Sebastian Funke, Jana Treml, Anja Beschnitt, Natarajan Perumal, Caroline Manicam, Norbert Pfeiffer, Franz H Grus
Proper sample preparation protocols represent a critical step for liquid chromatography-mass spectrometry (LC-MS)-based proteomic study designs and influence the speed, performance and automation of high-throughput data acquisition. The main objective of this study was to compare two commercial solid-phase extraction (SPE)-based sample preparation protocols (comprising SOLAµTM HRP SPE spin plates from Thermo Fisher Scientific and ZIPTIP® C18 pipette tips from Merck Millipore) for analytical performance, reproducibility, and analysis speed...
December 3, 2018: International Journal of Molecular Sciences
Hui Tang, Jin-Kui Ma, Lin Chen, Li-Wen Jiang, Jing Xie, Pao Li, Jing He
This study optimized the headspace solid phase microextraction (HS-SPME) conditions for the analysis of the volatile flavor compounds of Chinese south stinky tofu brine by gas chromatography-mass spectrometry (GC-MS). The optimum HS-SPME conditions established were as follows: polar column CD-WAX, white 85 μm polyella extractor, extraction temperature 60 °C, equilibrium time 20 min, extraction time 40 min. Under these conditions, a total of 63 volatile flavor compounds in five stinky tofu brines were identified...
November 30, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Ioannis K Karabagias, Miguel Maia, Vassilios K Karabagias, Ilias Gatzias, Anastasia V Badeka
The present study was conducted to evaluate the quality and bio-functional properties of Portuguese honeys of different botanical and geographical origins. Quality parameter analyses included the determination of palynological (predominant, secondary, minor and isolated pollen percentage), physicochemical (°Brix, moisture content, pH, electrical conductivity, free acidity, total dissolved solids, salinity, vitamin C content and specific weight) including colour-metrics (CIELAB, Pfund and colour intensity determinations), along with volatile compounds identification using solid phase micro-extraction coupled to gas chromatography mass spectrometry...
November 30, 2018: Foods (Basel, Switzerland)
Vincenzo Ferrone, Roberto Cotellese, Annadomenica Cichella, Paolo Raimondi, Maura Carlucci, Paola Palumbo, Giuseppe Carlucci
A simple and rapid ultra high-performance liquid chromatographic (UHPLC) for the simultaneous determination of meropenem and ciprofloxacin in human plasma was developed and validate. All the analytes were separated in less than 5 min. A solid-phase extraction method was applied from samples preparation. Analytical separation was performed on a Poroshell SB C18 column (50 x 2.1 mm, 2.7 μm particle size) with PDA detection. Meropenem and ciprofloxacin were carried out at a wavelength 300 and 277 nm, respectively...
December 4, 2018: Biomedical Chromatography: BMC
Yuqi Jiang, Zhunmei Ning, Shuang Li
Ionic liquid-based ultrasonic-assisted extraction (IL-UAE) was developed to extract and separate the isochlorogenic acid C (ICGA) from a cultivar of Chrysanthemum morifolium ( Chrysanthemummorifolium Ra Tnat .). The influencing parameters, including IL concentration, liquid-to-solid ratio, and ultrasonic time, were optimized using response surface methodology. Of the ILs studied, 1-butyl-3-methylimidazolium bromide [(Bmim)Br] exhibited the best extraction ability. The optimized conditions included liquid-to-solid ratio of 23...
November 2018: Food Science & Nutrition
Oluwafemi A Adebo, Patrick B Njobeh, Steve C Z Desobgo, Mark Pieterse, Eugenie Kayitesi, Derek T Ndinteh
The objective of this study was to investigate the volatile flavor compounds of nkui , a Cameroonian food, using solid phase microextraction (SPME) and a two-dimensional gas chromatography time of flight mass spectrometry GC×GC-TOF-MS system. Using SPME, volatile compounds were extracted from nkui and analyzed by GC×GC-TOF-MS. The data retrieved revealed the presence of flavor volatiles including acids (20%), alcohols (4%), aldehydes (10%), aromatic compounds (4%), esters (7%), furans (4%), ketones (11%), terpenes and terpernoids (27%)...
November 2018: Food Science & Nutrition
Pappula Nagaraju, Balaji Kodali, Peda Varma Datla, Surya Prakasarao Kovvasu
An accurate, highly sensitive, and precise method for quantitative analysis of tramadol (TMD) and gabapentin (GBP) by high performance liquid chromatography and tandem mass spectrometry in human plasma was proposed and validated successfully using venlafaxine and pregabalin as internal standards (ISTDs), respectively. An aliquot of 200 μ L of plasma was mixed with internal standard dilution and extraction was performed by using solid phase extraction (SPE) technique. Peak resolution was achieved on Phenomenex PFP column (50×4...
2018: International Journal of Analytical Chemistry
Kwangu M Kanama, Adegbenro P Daso, Lizzy Mpenyana-Monyatsi, Marthie A A Coetzee
The presence of 17 pharmaceutical and personal care products (PPCPs) belonging to various therapeutic categories was investigated in two hospital wastewater treatment plants (WWTPs) in North West Province, South Africa. The compounds were extracted from wastewater samples by solid-phase extraction and analysed by liquid chromatography-tandem mass spectrometry. The results showed that ofloxacin, chloramphenicol, and bezafibrate were generally below the limit of quantification (LOQ) in the analysed samples. Acetaminophen and ibuprofen were the dominant pharmaceuticals in the influent streams with corresponding concentrations ranging from 21 to 119 μ g/L and 0...
2018: Journal of Toxicology
Hina Javed, Aminul Islam, Anjali Chauhan, Suneel Kumar, Sushil Kumar
Graphene oxide (GO) was immobilized innovatively through azo spacer arm onto the surface of polymeric Amberlite XAD-16 resin in order to expose all oxygen functionalities freely available for metal ions coordination and further modification with picolylamine which governs selectivity. The GO Amberlite XAD-16 picolylamine enables the development of SPE column coupled with ICP-OES for preconcentration and determination of Pb (II) and Cu (II) in water and fish samples. Elution was performed by mild acid (2M HCl) no other carcinogenic organic solvent was used, prevents ligand leaching...
December 3, 2018: Scientific Reports
Idalina Bragança, Paulo C Lemos, Cristina Delerue-Matos, Valentina F Domingues
3-Phenoxybenzoic acid (3-PBA) is a shared metabolite of several synthetic pyrethroid pesticides (SPs) resulting from environmental degradation of parent compounds and thus occurs frequently as a residue in samples. Hence, the importance of 3-PBA evaluation after pyrethroid application. There is a gap of analytical methods to determine 3-PBA in soil samples. Therefore, an analytical method that combines the solid-phase extraction (SPE) and gas chromatography-mass spectrometry (GC/MS) detection has been developed for the determination of 3-PBA in soil samples...
November 30, 2018: Environmental Science and Pollution Research International
Odelia Nahum, Amanda Thomas, Brynn Levy
A prenatal noninvasive genetic screening test that yields a positive result typically warrants further direct assessment of fetal DNA following an invasive procedure. The precious nature of these invasively acquired samples, combined with the time sensitive nature with which results should be reported, demands that the methodologies used for analysis be quick, efficient, and dependable.Prenatal diagnosis has been performed using DNA extracted from amniotic fluid and chorionic villi for several decades, and more recently methodologies have been developed to extract cell free fetal DNA from amniotic fluid...
2019: Methods in Molecular Biology
Hiroko Kasai, Yui Kubota
Volatile components originating from Lavandula angustifolia Hidcote and Lavandula x intermedia Grosso plants cultivated in a medicinal plant garden of Hoshi University located in southern Tokyo were investigated using thermal desorption-GC-MS. Sampling of the flowers and herbs of the lavender was performed at different developmental stages, i.e., summer, autumn, and winter (herbs only) using solid phase micro extraction fibers. Linalool, linalyl acetate, β-caryophyllene, β-myrcene, α-ocimene, β-ocimene, and terpinen-4-ol were the predominant constituents originating from the flowers of both plants...
2018: Yakugaku Zasshi: Journal of the Pharmaceutical Society of Japan
Selda Mercan, Merve Kuloglu, Tugba Tekin, Zeynep Turkmen, Ahmet Ozgur Dogru, Ayse N Safran, Munevver Acikkol, Faruk Asicioglu
Wastewater-based epidemiology is a well-established and complementary approach for monitoring illicit drug use in the general population. In this study, amphetamine (AMP), methamphetamine (METH), 3,4-methylenedioxymethamphetamine (MDMA), cocaine (COC) (from benzoylecgonine), and cannabis (from THC-COOH) consumption levels were investigated for the first time in Turkey (Istanbul). A solid-phase extraction method was applied to influent wastewater samples collected from two districts, Beyoglu and Catalca. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis was conducted with electrospray ionization in positive mode...
November 24, 2018: Science of the Total Environment
Rosimeire Resende Dos Santos, Lívia Dias Vidotti Leal, Zenilda de Lourdes Cardeal, Helvécio Costa Menezes
Polycyclic aromatic hydrocarbons (PAHs) are food contaminants; besides, their oxygenated (oxy-PAHs) and nitrated (nitro-PAHs) derivatives have also been detected in some foods. This is worrying because these derivatives may be more toxic than PAHs. This study presents a new method for the determination of PAHs and their oxygenated and nitrated derivatives in coffee brew. The analytes were extracted by cold fiber solid phase microextraction (CF-SPME) with analysis by gas chromatography/mass spectrometry. The developed method presented good precision with intra-assay and inter-assay, ranged from 4...
November 26, 2018: Journal of Chromatography. A
Tahereh Golzari Aqda, Mehrnoosh Raoofi, Shima Behkami, Habib Bagheri
In this study, a method was described for the extraction of three antibiotic residues from cow milk samples using a graphene oxide-starch-based nanocomposite. The prepared nanocomposites were employed as an extractive phase for micro-solid phase extraction of antibiotics from cow milk samples. The extracted antibiotics, i.e. amoxicillin, ampicillin and cloxacillin, were subsequently analyzed by high-performance liquid chromatography-ultraviolet detection (HPLC-UV). Important variables associated with the extraction and desorption efficiency were optimized...
November 26, 2018: Journal of Chromatography. A
Sayyed Hossein Hashemi, Massoud Kaykhaii, Ahmad Jamali Keikha, Zahra Sajjadi
In this paper, a rapid, selective and effective technique, pipette-tip solid phase extraction based on molecularly imprinted polymer, was used for extraction and pre-concentration of methyl red (MR) prior to its determination by spectrophotometer. Variables influencing extraction efficiency including type and volume of eluent solvent, sample volume, number of cycles of extraction and elution, amount of sorbent and pH of the sample solution were optimized with two methods of one-variable-at-a-time and response surface methodology (RSM)...
December 2018: Marine Pollution Bulletin
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"