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https://www.readbyqxmd.com/read/29151005/synthesis-of-a-novel-polymeric-magnetic-solid-phase-extraction-adsorbent-for-selective-extraction-of-amphetamine-from-urine-samples-coupled-with-high-performance-liquid-chromatography
#1
Arezou Taghvimi, Marjan Ghorbani, Hamed Hamishehkar
A novel pH-responsive block copolymer (Poly ethylene glycol-b-poly (N,N-dimethylaminoethylmethacrylate-co-maleic acid) was designed for the decoration and stabilization of magnetic nanoparticles (MNPs) to apply as an efficient magnetic nano adsorbent for extraction of amphetamine (AM) from biological urine samples to be determined by high performance liquid chromatography ultra violet detector (HPLC-UV). Full characterization of the synthesized Polymeric magnetic nanoparticles (PMNPs) were followed by various techniques like Fourier transform infrared (FT-IR) spectroscopy, powder x-ray diffraction (XRD), scanning electron microscopy (SEM), and vibrating sample magnetometer (VSM)...
November 18, 2017: Drug Testing and Analysis
https://www.readbyqxmd.com/read/29150928/application-of-high-speed-counter-current-chromatography-and-hplc-to-separate-and-purify-of-three-polyacetylenes-from-platycodon-grandiflorum
#2
Bao Chen, Zhengbo Liu, Yuwei Zhang, Wei Li, Yanjun Sun, Yufang Wang, Yanhua Wang, Yinshi Sun
Three polyacetylenes were isolated and purified from Platycodon grandiflorum A. DC for the first time by high-speed counter-current chromatography using a two-phase solvent system composed of hexane/ethyl acetate/methanol/water (1:31:1:31, v/v/v/v) and high-performance liquid chromatography with an Agilent ZORBAX(®) SB-C18 column (4.6 mm × 150 mm, 5 μm). After separation by high-speed counter-current chromatography and high-performance liquid chromatography, we obtained 3.5 mg of platetyolin A, 4.1 mg of platetyolin B, and 18...
November 18, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/29150925/one-pot-synthesis-of-a-multi-template-molecularly-imprinted-polymer-for-the-extraction-of-six-sulfonamide-residues-from-milk-before-hplc-with-diode-array-detection
#3
Maria Kechagia, Victoria Samanidou, Abuzar Kabir, Kenneth G Furton
A highly selective molecularly imprinted polymer sorbent was synthesized and employed for the simultaneous determination of six sulfonamide antibiotic residues (sulfanilamide, sulfacetamide, sulfadiazine, sulfathiazole, sulfamerazine and sulfamethizole) in milk samples. Multi-analyte imprinted particles were used as sorbent in solid phase extraction. Sulfonamides were separated on a high-performance liquid chromatography column (Merck-Lichrospher RP18e, 5 μm 250 × 4 mm) and further identified and quantified by diode array detection...
November 18, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/29150709/simultaneous-detection-of-nadph-consumption-and-h2o2-production-using-the-ampliflu%C3%A2-red-assay-for-screening-of-p450-activities-and-uncoupling
#4
Lisa K Morlock, Dominique Böttcher, Uwe T Bornscheuer
Cytochrome P450s belong to a large and diverse group of heme-containing enzymes. These monooxygenases catalyze the incorporation of a single atom of molecular oxygen into their substrate. In contrast to most other enzymes, the activity of P450 enzymes is not only dependent on substrate and cofactor availability and reaction conditions, but also depends on the coupling efficiency of the catalytic cycle itself. Through the electron transfer from NAD(P)H to the heme-center of the P450, the enzyme becomes activated and binds oxygen...
November 17, 2017: Applied Microbiology and Biotechnology
https://www.readbyqxmd.com/read/29150064/metal-organic-frameworks-as-stationary-phase-for-application-in-chromatographic-separation
#5
REVIEW
Juan Zhang, Zilin Chen
Metal-organic frameworks (MOFs) as a subclass of coordination polymers, have attracted wide interest in various field. Herein, we focus on its application in chromatographic separation due to its excellent physical and chemical properties such as large surface area, high porosity, uniform pore sizes and structural diversity. In 2014, a review was published to summarize the most significant advances in MOFs, and their applications in separation science. The present review was an extensive update on applications of MOFs in chromatographic separation from 2014 to the present such as high-performance liquid chromatography (HPLC), capillary electrochromatography (CEC), nano-liquid chromatography (nano-LC), and gas chromatography (GC)...
October 27, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/29149736/graphene-oxide-reinforced-ionic-liquid-functionalized-adsorbent-for-solid-phase-extraction-of-phenolic-acids
#6
Xiudan Hou, Xiaofeng Lu, Sheng Tang, Licheng Wang, Yong Guo
An environmental friendly sorbent of polymeric ionic liquids modified graphene oxide-grafted silica (PILs@GO@Sil) was synthesized for solid-phase extraction (SPE) of phenolic acids. The sorbent was prepared via a chemical layer-to-layer fabrication including amidation reaction, surface radical chain-transfer polymerization and in situ anion exchange. After modification with PILs, the silica surface had higher positive potential so that it would exhibit stronger electrostatic interaction for acidic compounds compared with GO@Sil...
November 12, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/29149712/detection-of-perfluoroalkyl-acids-and-sulphonates-in-italian-eel-samples-by-hplc-hrms-orbitrap
#7
Luca Maria Chiesa, Maria Nobile, Elisa Pasquale, Claudia Balzaretti, Petra Cagnardi, Doriana Tedesco, Sara Panseri, Francesco Arioli
Perfluoroalkyl substances (PFASs) contain one or more carbon-bound hydrogens substituted by fluorine. Since the 1950s, these compounds have been used to manufacture fat- and water-resistant fabrics, paper and food containers, and to produce photographic films, firefighting foams, detergents and insecticides. The widespread use and global distribution of PFASs, have led to their accumulation in the environment. Food, particularly fish and other seafood, is considered the main route of human exposure to PFASs...
October 27, 2017: Chemosphere
https://www.readbyqxmd.com/read/29149702/an-hplc-tandem-mass-spectrometry-for-quantification-of-et-26-hcl-and-its-major-metabolite-in-plasma-and-application-to-a-pharmacokinetic-study-in-rats
#8
Xu Chen, Wensheng Zhang, Sandy Rios, Miriam B Morkos, Xiaoli Ye, Gen Li, Xuehua Jiang, Zhijun Wang, Ling Wang
ET-26-HCl is a new analog of etomidate, a short-acting anesthetic drug, with less adrenal cortex inhibition. The pharmacokinetics of ET-26-HCl in rats needs to be determined for future clinical trials in human subjects. In order to facilitate the pharmacokinetic study, a liquid chromatography based tandem mass spectrometric (HPLC-MS/MS) method was developed and validated for quantification of ET-26-HCl and its major metabolite, ET-26-acid. These two compounds and gabapentin (internal standard) were extracted using a protein precipitation method with methanol and detected by Multiple Reaction Monitoring of m/z transition of 275...
November 8, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/29149042/comparative-study-of-biological-activities-of-venom-from-colubrid-snakes-rhabdophis-tigrinus-yamakagashi-and-rhabdophis-lateralis
#9
Yumiko Komori, Toru Hifumi, Akihiko Yamamoto, Atsushi Sakai, Manabu Ato, Kyoko Sawabe, Toshiaki Nikai
Rhabdophis lateralis, a colubrid snake distributed throughout the continent of Asia, has recently undergone taxonomic revisions. Previously, Rhabdophis lateralis was classified as a subspecies of R. tigrinus (Yamakagashi) until 2012, when several genetic differences were discovered which classified this snake as its own species. To elucidate the toxicity of venom from this poorly studied colubrid, various biological activities were compared between the venom from the two snake species. The components of their venom were compared by the elution profiles of reversed-phase HPLC and SDS-PAGE, and gel filtrated fractions were tested for effects on blood coagulation...
November 17, 2017: Toxins
https://www.readbyqxmd.com/read/29148846/preparation-and-evaluation-of-curcumin-loaded-self-assembled-micelles
#10
Lu-Lu Wang, Dan-Dan He, Shu-Xia Wang, Yun-Hao Dai, Jian-Ming Ju, Cheng-Lei Zhao
Objective Curcumin being used to treat various chronic diseases while its poor bioavailability issue limited its wide clinical application as a therapeutic agent. The aim of this work was to prepare curcumin-loaded self-assembled micelles using soluplus and solutol®HS15 (SSCMs) to enhance curcumin's solubility and thus oral bioavailability. Methods Optimum formulation was investigated and the optimized ratio of drugs and excipients was obtained and the SSCMs were prepared via ethanol solvent evaporation method...
November 17, 2017: Drug Development and Industrial Pharmacy
https://www.readbyqxmd.com/read/29148716/rapid-quantification-of-4-4-methylenedianiline-by-surface-enhanced-raman-spectroscopy
#11
Samuel L Kleinman, Mark C Peterman, Merwan Benhabib, Michael T Cheng, James D Hudson, Rachel E Mohler
Methylenedianiline (MDA) is a common industrial chemical with health and product safety concerns. Common analysis methods require many steps including extraction and derivatization ending in GC-MS or HPLC analysis, which minimize its use as an on-line or at-line technique. The procedure can take hours, prohibiting its use as a real-time decision-making tool as well as using valuable resources and laboratory space. The new method presented here has been validated for MDA quantification in industrial grease samples over the concentration range of 1-40 ppm 4,4'-MDA...
November 17, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/29148595/determination-of-cefoperazone-and-sulbactam-in-serum-by-hplc-ms-ms-an-adapted-method-for-therapeutic-drug-monitoring-in-children
#12
Xiu-Jun Wu, Xin Huang, Hai-Yan Shi, Xing-Kai Chen, Qian Dong, Guo-Xiang Hao, Yan Li, Yi Zheng, Wei Zhao
A rapid, accurate and specific high-performance liquid chromatographic -tandem mass spectrometry method has been validated for the simultaneous determination of cefoperazone and sulbactam in a small volume sample for children. A Shim-pack XR-ODS C18 column with gradient elution of water (0.1% formic acid) and acetonitrile (0.1% formic acid) solution was used for separation at a flow rate of 0.3 mL/min. The calibration curves of two analytes in serum showed excellent linearity over the concentration ranges of 0...
November 17, 2017: Biomedical Chromatography: BMC
https://www.readbyqxmd.com/read/29148163/development-and-validation-of-a-high-performance-liquid-chromatography-method-for-determination-of-lisinopril-in-human-plasma-by-magnetic-solid-phase-extraction-and-pre-column-derivatization
#13
Noushin Rastkari, Reza Ahmadkhaniha
A sensitive, reliable and simple HPLC method was developed for the determination of lisinopril in human plasma. The method consists of extraction and clean-up steps based on magnetic solid-phase extraction and pre-column derivatization with a fluorescent reagent. The mobile phase consisted of a mixture of methanol-sodium dihydrogen phosphate (pH 3.0; 0.005 m; 75:25, v/v). The flow rate was set at 0.7 mL/min. Fluorescence detection was performed at 470nm excitation and 530nm emission wavelengths. Total chromatography run time was 5 min...
November 16, 2017: Biomedical Chromatography: BMC
https://www.readbyqxmd.com/read/29148050/the-pharmacokinetics-of-morphine-and-codeine-in-human-plasma-and-urine-after-oral-administration-of-qiangli-pipa-syrup
#14
Bin-Bin Guo, Yu-Qiao Zhang, Sheng-Feng Wang, Jin-Song Ding, Wen-Hu Zhou
Papaveris pericarpium, a natural source of morphine and codeine, is the principal active component in many antitussive traditional Chinese medicines. We herein report the first PK study of papaveris pericarpium in human plasma and urine following oral administration of single (15, 30, 60 mL) and multiple dose (15 mL) of Qiangli Pipa Syrup (MOR 0.1 mg/mL, COD 0.028 mg/mL) by monitoring morphine and codeine using a HPLC-MS/MS method. Their Tmax and t1/2 values are independent of dosages, while the AUC0-t linearly increased with higher dosages, indicating linear PK characteristics...
November 17, 2017: Journal of Forensic Sciences
https://www.readbyqxmd.com/read/29147966/polyamine-concentration-is-increased-in-thoracic-ascending-aorta-of-patients-with-bicuspid-aortic-valve
#15
Amalia Forte, Mario Grossi, Ciro Bancone, Marilena Cipollaro, Marisa De Feo, Per Hellstrand, Lo Persson, Bengt-Olof Nilsson, Alessandro Della Corte
Polyamines are cationic molecules synthesized via a highly regulated pathway, obtained from the diet or produced by the gut microbiota. They are involved in general molecular and cellular phenomena that play a role also in vascular disease. Bicuspid aortic valve (BAV) is a congenital malformation associated to a greater risk of thoracic ascending aorta (TAA) aneurysm, whose pathogenesis is not yet well understood. We focused on differential analysis of key members of polyamine pathway and on polyamine concentration in non-dilated TAA samples from patients with either stenotic tricuspid aortic valve (TAV) or BAV (diameter ≤ 45 mm), vs...
November 17, 2017: Heart and Vessels
https://www.readbyqxmd.com/read/29147097/characterization-of-paenibacillus-sp-mbt213-isolated-from-raw-milk-and-its-ability-to-convert-ginsenoside-rb1-into-ginsenoside-rd-from-panax-ginseng
#16
Gereltuya Renchinkhand, Soo Hyun Cho, Magsar Urgamal, Young W Park, Joong Hyeon Nam, Hyung Churl Bae, Gyu Yong Song, Myoung Soo Nam
This study was conducted to isolate and characterize Paenibacillus sp. MBT213 possessing β-glucosidase activity from raw milk, and examine the enzymatic capacity on the hydrolysis of a major ginsenoside (Rb1). Strain MBT213 was found to have a high hydrolytic ability on ginsenoside Rb1 by Esculin Iron Agar test. 16S rDNA analysis revealed that MBT213 was Paenibacillu sp. Crude enzyme of MBT213 strain exhibited high conversion capacity on ginsenoside Rb1 into ginsenoside Rd proven by TLC and HPLC analyses. The API ZYM kit confirmed that Paenibacillu sp...
2017: Korean Journal for Food Science of Animal Resources
https://www.readbyqxmd.com/read/29146374/formation-kinetics-of-furfuryl-alcohol-in-a-coffee-model-system
#17
Abdullatif Albouchi, Michael Murkovic
The production of furfuryl alcohol from green coffee during roasting and the effect of multiple parameters on its formation were studied employing HPLC-DAD. Results show that coffee produces furfuryl alcohol in larger quantities (418µg/g) compared to other beans or seeds (up to 132µg/g) roasted under the same conditions. The kinetics of furfuryl alcohol production resemble those of other process contaminants (e.g., HMF, acrylamide) produced in coffee roasting, with temperature and time of roasting playing significant roles in quantities formed...
March 15, 2018: Food Chemistry
https://www.readbyqxmd.com/read/29146354/a-novel-calcium-binding-peptide-from-antarctic-krill-protein-hydrolysates-and-identification-of-binding-sites-of-calcium-peptide-complex
#18
Hu Hou, Shikai Wang, Xiao Zhu, Qiqi Li, Yan Fan, Dong Cheng, Bafang Li
Trypsin was used for preparing peptides with high calcium-binding capacity from Antarctic krill. Hydroxyapatite chromatography (HAC), size-exclusion chromatography (SEC), and reversed phase high performance liquid chromatography (RP-HPLC) were used to capture and purify calcium-binding peptides. The peptide sequence was determined to be VLGYIQIR (N- to C-terminal, MW = 960.58 Da), using LTQ Orbitrap XL. According to the results of FTIR and mass spectrometry, chelating site of calcium ions may possibly involve the carbonal or amino groups of Gln, Ile and Arg residues...
March 15, 2018: Food Chemistry
https://www.readbyqxmd.com/read/29146349/analysis-of-alternariol-and-alternariol-monomethyl-ether-in-foodstuffs-by-molecularly-imprinted-solid-phase-extraction-and-ultra-high-performance-liquid-chromatography-tandem-mass-spectrometry
#19
A Rico-Yuste, J Walravens, J L Urraca, R A G Abou-Hany, A B Descalzo, G Orellana, M Rychlik, S De Saeger, M C Moreno-Bondi
Molecularly imprinted porous polymer microspheres selective to Alternaria mycotoxins, alternariol (AOH) and alternariol monomethyl ether (AME), were synthesized and applied to the extraction of both mycotoxins in food samples. The polymer was prepared using 4-vinylpiridine (VIPY) and methacrylamide (MAM) as functional monomers, ethylene glycol dimethacrylate (EDMA) as cross-linker and 3,8,9-trihydroxy-6H-dibenzo[b,d]pyran-6-one (S2) as AOH surrogate template. A molecularly imprinted solid phase extraction (MISPE) method has been optimized for the selective isolation of the mycotoxins from aqueous samples coupled to HPLC with fluorescence (λex=258nm; λem=440nm) or MS/MS analysis...
March 15, 2018: Food Chemistry
https://www.readbyqxmd.com/read/29146316/comparative-evaluation-of-three-different-elisa-assays-and-hplc-esi-itms-ms-for-the-analysis-of-n-%C3%AE%C2%B5-carboxymethyl-lysine-in-food-samples
#20
Armando Gómez-Ojeda, Sarahi Jaramillo-Ortíz, Katarzyna Wrobel, Kazimierz Wrobel, Gloria Barbosa-Sabanero, Claudia Luevano-Contreras, Maria Pia de la Maza, Jaime Uribarri, Ma Dolores Del Castillo, Ma Eugenia Garay-Sevilla
N(ε)-carboxymethyl-lysine (CML) is measured in food, but there is a controversy concerning the most convenient yet reliable method(s) for this task. This work compares three different ELISA assays and HPLC-ESI-ITMS/MS for the analysis of CML in several food items. The four methods showed the same decreasing order of CML concentration: beef, bacon>chicken > fish>dairy products>grain products>fruits/vegetables. HPLC-ESI-ITMS/MS results highly correlated with those obtained by ELISA performed with monoclonal CML-antibody (β=0...
March 15, 2018: Food Chemistry
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