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https://www.readbyqxmd.com/read/28811019/introducing-a-new-and-rapid-microextraction-approach-based-on-magnetic-ionic-liquids-stir-bar-dispersive-liquid-microextraction
#1
Alberto Chisvert, Juan L Benedé, Jared L Anderson, Stephen A Pierson, Amparo Salvador
With the aim of contributing to the development and improvement of microextraction techniques, a novel approach combining the principles and advantages of stir bar sorptive extraction (SBSE) and dispersive liquid-liquid microextraction (DLLME) is presented. This new approach, termed stir bar dispersive liquid microextraction (SBDLME), involves the addition of a magnetic ionic liquid (MIL) and a neodymium-core magnetic stir bar into the sample allowing the MIL coat the stir bar due to physical forces (i.e., magnetism)...
August 29, 2017: Analytica Chimica Acta
https://www.readbyqxmd.com/read/28808779/optimisation-of-extraction-methods-and-quantification-of-benzo-a-pyrene-and-benz-a-anthracene-in-yerba-mat%C3%A3-tea-by-isotope-dilution-mass-spectrometry
#2
Ee Mei Gui, Ting Lu, Tang Lin Teo, Pui Sze Cheow, Tong Kooi Lee
A gas chromatography-isotope dilution mass spectrometry (GC-IDMS) technique was developed for the quantification of two heavy polyaromatic hydrocarbons (PAHs), benz[a]anthracene and benzo[a]pyrene, in yerba maté tea (maté). The optimisation of two extraction methods, namely liquid-liquid extraction and accelerated solvent extraction, was carried out. Both optimised methods were validated using a certified reference material of fine dust and the results were within the expanded uncertainties at 95% confidence level...
August 14, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28808600/simultaneous-determination-of-11-compounds-in-gualou-guizhi-granule-and-pharmacokinetics-study-by-uplc-ms-ms
#3
Chengtao Sun, Wen Xu, Yuqin Zhang, Lishuang Yu, Miao Ye, Kedan Chu, Wei Xu, Yu Lin
A rapid and sensitive ultrafast performance liquid chromatography-tandem mass spectrometry method (UPLC-MS/MS) was developed for the simultaneous determination of 11 compounds in Gualou Guizhi Granule (GLGZG), including liquiritin, isoliquiritin, liquirtin apioside, isoliquiritin apioside, liquiritigenin, isoliquiritigenin, glycyrrhizic acid, glycyrrhetinic acid, paeoniflorin, albiflorin, and paeoniflorin sulfonate in rat plasma. UPLC-MS/MS assay with negative ion mode was performed on a Waters CORTECS C18 (2...
2017: Journal of Analytical Methods in Chemistry
https://www.readbyqxmd.com/read/28807090/mass-spectral-characterization-and-uplc-quantitation-of-3-deoxyanthocyanidins-in-sorghum-bicolor-varietals
#4
Nathan P Stern, Jatinder Rana, Amitabh Chandra, John Balles
A quantitative ultra-performance LC (UPLC) method was developed and validated to successfully separate, identify, and quantitate the major polyphenolic compounds present in different varieties of sorghum (Sorghum bicolor) feedstock. The method was linear from 3.2 to 320 ppm, with an r² of 0.99999 when using luteolinidin chloride as the external standard. Method accuracy was determined to be 99.5%, and precision of replicate preparations was less than 1% RSD. Characterization by UPLC-MS determined that the predominant polyphenolic components of the sorghum varietals were 3-deoxyanthocyanidins (3-DXAs)...
August 10, 2017: Journal of AOAC International
https://www.readbyqxmd.com/read/28804803/comparison-of-sample-preparation-procedures-on-metal-loid-fractionation-patterns-in-lichens
#5
E M Kroukamp, T W Godeto, P B C Forbes
The effects of different sample preparation strategies and storage on metal(loid) fractionation trends in plant material is largely underresearched. In this study, a bulk sample of lichen Parmotrema austrosinense (Zahlbr.) Hale was analysed for its total extractable metal(loid) content by ICP-MS, and was determined to be adequately homogenous (<5% RSD) for most elements. Several subsets of this sample were prepared utilising a range of sample preservation techniques and subjected to a modified sequential extraction procedure or to total metal extraction...
August 13, 2017: Environmental Monitoring and Assessment
https://www.readbyqxmd.com/read/28803650/lipid-determination-in-bone-marrow-and-mineralized-bone-tissue-from-sample-preparation-to-improved-high-performance-thin-layer-and-liquid-chromatographic-approaches
#6
Alexandrine During
In view of their key roles in the bone physiology (e.g., in the biomineralization process) and their potential implication in bone pathologies, an approach to study lipids in situ is needed. The aim of the present paper is to propose an original procedure to characterize lipids in both bone marrow (BM) and mineralized tissue (MT) compartments, taking into consideration sample preparation, lipid extraction and analytical issues, when using small sample size (≤ 0.5g of rat femurs). The potential contamination of the MT by marrow lipids and the poor accessibility of certain lipids from the MT - two major issues in bone handling - were taking care, respectively by performing two cleaning steps after BM removal and by adding a demineralization step to the overall lipid extraction protocol...
August 3, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28803648/automated-multi-filtration-cleanup-with-nitrogen-enriched-activated-carbon-material-as-pesticide-multi-residue-analysis-method-in-representative-crop-commodities
#7
Yuhong Qin, Jingru Zhang, Yifan Li, Qiuxiao Wang, Yangliu Wu, Lanshu Xu, Xiaojuan Jin, Canping Pan
An automated multi-filtration cleanup (Auto m-FC) method with nitrogen-enriched activated carbon material based on modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) extracts was developed. It was applied to pesticide multi-residue analysis in six representative crop commodities. The automatic device was aimed to improve the cleanup efficiency and reduce manual operation workload in cleanup step. By controlling extracts volume, flow rate and Auto m-FC cycles, the device could finish cleanup process accurately...
August 5, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28802857/spectrophotometric-methods-for-the-determination-of-urea-in-real-samples-using-silver-nanoparticles-by-standard-addition-and-2nd-order-derivative-methods
#8
Nauman Ali, Muhammad Ismail, Adnan Khan, Hamayun Khan, Sajjad Haider, Tahseen Kamal
In this work, we have developed simple, sensitive and inexpensive methods for the spectrophotometric determination of urea in urine samples using silver nanoparticles (AgNPs). The standard addition and 2nd order derivative methods were adopted for this purpose. AgNPs were prepared by chemical reduction of AgNO3 with hydrazine using 1,3-di-(1H-imidazol-1-yl)-2-propanol (DIPO) as a stabilizing agent in aqueous medium. The proposed methods were based on the complexation of AgNPs with urea. Using this concept, urea in the urine samples was successfully determined spectrophotometric methods...
August 1, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28802525/layered-double-hydroxides-based-ion-exchange-extraction-for-high-sensitive-analysis-of-non-steroidal-anti-inflammatory-drugs
#9
Wei Zhou, Chenlu Wang, Yikun Liu, Wenpeng Zhang, Zilin Chen
Layered double hydroxides (LDHs) are ideal sorbents for solid phase extraction (SPE) because of the excellent ion exchange capacity and high specific surface area. However, difficult elution of the analytes from the LDHs is a problem due to the strong ionic interaction between anions and LDHs. High concentrated NaOH solution is employed to elute the sample, but it not suitable for analyzing by HPLC. To solve this problem, a simple acid-base neutralization method was proposed after elution, and then the neutral samples were directly injected to HPLC for analysis...
July 15, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28802242/an-lc-ms-ms-method-for-simultaneous-determination-of-nine-steroidal-saponins-from-paris-polyphylla-var-in-rat-plasma-and-its-application-to-pharmacokinetic-study
#10
Guangyi Yang, Wei Lu, Meng Pan, Chenning Zhang, Yuan Zhou, Pei Hu, Ming Hu, Gao Song
Paris polyphylla var is an herbal plant herb widely used in Traditional Chinese Medicine. The purpose of this study is to develop an Ultra Performance Liquid Chromatography-tandem mass spectrometer (UPLC-MS) method to quantify the major components (i.e., nine saponins) from P. polyphylla in plasma samples. A UItra BiPh column (100×2.1mm, 5μm) was used with acetonitrile/0.1% formic acid in water as mobile phases. The analytes were quantified using a Waters XEVO TQ mass spectrometer via multiple reaction monitoring (MRM) with positive scan mode...
August 1, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28802217/comparatively-evaluating-the-pharmacokinetic-of-fifteen-constituents-in-normal-and-blood-deficiency-rats-after-oral-administration-of-xin-sheng-hua-granule-by-uplc-ms-ms
#11
Han-Qing Pang, Yu-Ping Tang, Yu-Jie Cao, Ya-Jie Tan, Yi Jin, Xu-Qin Shi, Sheng-Liang Huang, Da-Zheng Sun, Jin Sun, Zhi-Shu Tang, Jin-Ao Duan
Xin-Sheng-Hua Granule (XSHG), a famous traditional Chinese medicine prescription, are clinically applied for the treatment of postpartum disease through nourishing blood and promoting blood circulation. In this investigation, a multi-constituents (trigonelline, stachydrine hydrochloride, hydroxysafflor yellow A, chlorogenic acid, amygdalin, leonurine, liquiritin, ferulic acid, senkyunolide I, senkyunolide H, glycyrrhizic acid, senkyunolide A, ligustilide, butylidenephthalide and glycyrrhetinic acid) pharmacokinetic study of XSHG was conducted for the first time...
July 30, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28802025/simple-and-rapid-determination-of-zaltoprofen-in-human-plasma-by-manual-shaking-assisted-dispersive-liquid-liquid-microextraction-followed-by-liquid-chromatography-with-ultraviolet-detection
#12
Se Young Han, Kyung Min Jeong, Da Eun Yoo, Yan Jin, Eun Mi Kim, Su Hyun Kim, Seok-Yong Lee, Se-Hyung Kim, Jing Zhao, Jeongmi Lee
A readily applicable method was developed to determine the concentration level of zaltoprofen, a non-steroidal anti-inflammatory drug from the propionic acid family, in human plasma. This method is based on manual shaking-assisted dispersive liquid-liquid microextraction coupled with liquid chromatography with UV detection. Factors affecting the extraction efficiency were screened and optimized by experimental design using fractional factorial and central composite designs, respectively. Optimal conditions were: 220 μL of C2 H4 Cl2 (extraction solvent), 5 mL of 3...
August 12, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28801923/sensitive-liquid-chromatography-tandem-mass-spectrometry-method-for-the-determination-of-two-novel-highly-lipophilic-anti-cancer-drug-candidates-in-rat-plasma-and-tissues
#13
Shirin Hooshfar, Michael R Linzey, Daqing Wu, Lajos Gera, Kenza Mamouni, Xin Li, Yanhua Chen, Yang Yang, Oluwasegun Olorunyolemi, Michael G Bartlett
A simple and sensitive liquid chromatography/electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) method was developed and validated for determination of two highly lipophilic anti-cancer drug candidates, LG1980, and GH501, in rat plasma and tissues (liver, kidney and femur bones). LG1980 and GH501 were extracted from rat plasma and tissue homogenates using liquid-liquid extraction. The method provided a linear range of 1.0-200.0 ng/mL for GH501 in plasma and LG1980 in plasma and liver. For both analytes in other tissue homogenates the linear range was 2...
August 12, 2017: Biomedical Chromatography: BMC
https://www.readbyqxmd.com/read/28800528/comparison-of-three-officinal-species-of-callicarpa-based-on-a-biochemome-profiling-strategy-with-uhplc-it-ms-and-chemometrics-analysis
#14
Meng-Lu Chen, Wen-Qi Chang, Jian-Liang Zhou, Ying-Hao Yin, Wen-Rui Xia, Jian-Qun Liu, Li-Fang Liu, Gui-Zhong Xin
Traditional Chinese medicine (TCM) materials with closely related species are frequently fungible in clinical use. Therefore, holistic comparison of the composition in bioactive compounds is essential to evaluate whether they are equivalent in efficacy. Taking three officinal species of Callicarpa as a case, we proposed and validated a standardized strategy for the discrimination of closely related TCM materials, which focused on the extraction, profiling and multivariate statistical analysis of their biochemome...
August 1, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28798883/magnetic-solid-phase-extraction-using-fe3o4-sio2-magnetic-nanoparticles-followed-by-uv-vis-spectrometry-for-determination-of-paraquat-in-plasma-and-urine-samples
#15
Ou Sha, Yu Wang, Xin Yin, Xiaobing Chen, Li Chen, Shujun Wang
A rapid and simple method was optimized and validated for the separation and quantification of paraquat, a frequently used herbicide and a leading cause of fatal poisoning worldwide, at trace levels with UV-Vis spectrophotometry in plasma and urine samples by direct magnetic solid-phase extraction. Fe3O4@SiO2 nanoparticles (NPs) were used as the magnetic solid-phase extraction agents and the paraquat absorbed on NPs was eluted using NaOH and ascorbic acid. Upon optimization, paraquat could be extracted and concentrated from various samples by 35-fold...
2017: Journal of Analytical Methods in Chemistry
https://www.readbyqxmd.com/read/28795656/development-and-validation-of-multi-residue-analysis-for-tetracycline-antibiotics-in-feed-by-high-performance-liquid-chromatography-coupled-to-mass-spectrometry
#16
Ewelina Patyra, Krzysztof Kwiatek
A new multi-residue method for the analysis of the tetracycline antibiotics oxytetracycline, tetracycline, chlortetracycline, and doxycycline was developed and validated for animal feed. After extraction with 0.1M Na2EDTA-McIlvaine buffer (pH 4), the samples were centrifuged, purified by SPE (Strata-X-CW cartridges) and analyzed by high-performance liquid chromatography coupled to mass spectrometry. Validation of the method was performed according to the guidelines indicated in Commission Decision 2002/657/EC...
August 10, 2017: Food Additives & Contaminants. Part A, Chemistry, Analysis, Control, Exposure & Risk Assessment
https://www.readbyqxmd.com/read/28794337/determination-of-polychlorinated-biphenyls-in-fish-tissues-from-shanghai-seafood-markets-using-a-modified-quechers-method
#17
Yunyun Cui, Zhengquan Wang, Jian Cong, Liping Wang, Yuan Liu, Xichang Wang, Jing Xie
Optimized Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) pretreatment methods for determination of six polychlorinated biphenyls (PCBs) residues in fish and aquatic invertebrates samples were investigated. Large volume injection (LVI) coupled gas chromatography tandem mass spectrometry (GC-MS/MS) with selected reaction monitoring (SRM) was used to provide a very sensitive and selective means of analyzing PCBs via internal calibration. Three analytical processes were validated and compared, and the florisil Celite(®)545 pretreatment method was selected...
2017: Analytical Sciences: the International Journal of the Japan Society for Analytical Chemistry
https://www.readbyqxmd.com/read/28792458/amalgam-electrode-based-electrochemical-detector-for-on-site-direct-determination-of-cadmium-ii-and-lead-ii-from-soils
#18
Lukas Nejdl, Jindrich Kynicky, Martin Brtnicky, Marketa Vaculovicova, Vojtech Adam
Toxic metal contamination of the environment is a global issue. In this paper, we present a low-cost and rapid production of amalgam electrodes used for determination of Cd(II) and Pb(II) in environmental samples (soils and wastewaters) by on-site analysis using difference pulse voltammetry. Changes in the electrochemical signals were recorded with a miniaturized potentiostat (width: 80 mm, depth: 54 mm, height: 23 mm) and a portable computer. The limit of detection (LOD) was calculated for the geometric surface of the working electrode 15 mm² that can be varied as required for analysis...
August 9, 2017: Sensors
https://www.readbyqxmd.com/read/28792093/polymer-spray-mass-spectrometric-detection-and-quantitation-of-hydrophilic-compounds-and-some-narcotics
#19
Maria T Dulay, Richard N Zare
RATIONALE: High throughput screening of biofluids is essential in monitoring concentration of a variety of drugs to determine their efficacy and toxicity. Organosiloxane polymers prepared by sol-gel chemistry as sample supports and electrospray-ionization emitters in a single material and as an alternative to paper substrates, is described in this study. METHODS: Hydrophobic drugs and hydrophilic streptomycin were analyzed by polymer-spray MS with an LTQ-Orbitrap mass spectrometer...
August 9, 2017: Rapid Communications in Mass Spectrometry: RCM
https://www.readbyqxmd.com/read/28790408/graphene-nanoplatelets-based-matrix-solid-phase-dispersion-microextraction-for-phenolic-acids-by-ultrahigh-performance-liquid-chromatography-with-electrochemical-detection
#20
Li-Qing Peng, Ling Yi, Qiu-Cheng Yang, Jun Cao, Li-Jing Du, Qi-Dong Zhang
A simple, rapid and eco-friendly approach based on matrix solid-phase dispersion microextraction (MSPDM) followed by ultrahigh performance liquid chromatography coupled with electrochemical detection (UHPLC-ECD) was presented for the microextraction and determination of six phenolic acids in a plant preparation (Danshen tablets). The parameters that influenced the extraction performance of phenolic acids were investigated and optimized. The optimal MSPDM conditions were determined as follows: sorbent, using graphene nanoplatelets with sample/sorbent ratio of 1:1, grinding time set at 60 s, and 0...
August 8, 2017: Scientific Reports
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