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https://read.qxmd.com/read/30877981/simultaneous-determination-of-seven-effective-components-of-tripterygium-glycosides-in-human-biological-matrices-by-ultra-performance-liquid-chromatography-triple-quadrupole-mass-spectrometry
#1
Xi Du, Xin He, Yuhong Huang, Bin Fu, Bingnan Liang, Chunxiao Lv, Yan Li, Xue Gao, Yangyang Wang
This paper developed a novel, sensitive, and selective ultra-performance liquid chromatography-triple quad mass spectrometry method to simultaneously determine seven effective constituents (triptolide, triptophenolide, celastrol, wilforgine, wilforine, wilfordine and wilfortrine) of Tripterygium glycosides (GTW) in human serum and urine. The chromatographic separation was performed on the C18 column using an ammonium acetate buffer solution-acetonitrile (both containing 0.1% formic acid) in a gradient program with a flow rate of 0...
February 25, 2019: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://read.qxmd.com/read/30877932/a-validated-uhplc-ms-ms-method-for-measurement-of-pharmacokinetics-and-tissue-distribution-of-trolline-in-rat
#2
Nan Zhao, Qi Sun, Kamara Mohamed Olounfeh, Qi-Li Chen, Jing-Wei Liang, Shan Wang, Lin Wang, Yang Song, Fan-Hao Meng
As a novel alkaloid, trolline is a potential methionine aminopeptidase Ⅱ inhibitor. However, up to now, no informations about the quantification of trolline were available in biosamples. In this study, a simple, specific and sensitive analytical method based on UHPLC-MS/MS method has been established and validated for determination of trolline in rat plasma and tissues after intravenous administration. Sample preparation was carried out by a simple liquid-liquid extraction and carbamazepine was used as internal standard (I...
March 6, 2019: Journal of Pharmaceutical and Biomedical Analysis
https://read.qxmd.com/read/30877931/characterization-of-degradation-products-and-process-related-impurity-of-sutezolid-by-liquid-chromatography-electrospray-ionization-tandem-mass-spectrometry
#3
Kaijing Guo, Tingting Zhang, Yanan Wang, Bo Jin, Chen Ma
Sutezolid was a new oxazolidinone compound used for the treatment of M. tuberculosis. This study describes the separation, characterization and in silico toxicity prediction of three degradation products and one process-related impurity of sutezolid. Sutezolid was subjected to forced degradation including hydrolytic (acidic, alkaline and neutral), oxidative, photolytic and thermal conditions according to the ICH guidelines Q1A(R2) and Q3A(R2) and yielded three degradation products. Two degradation products were formed under oxidative condition and one degradation product was formed in hydrolytic condition...
March 6, 2019: Journal of Pharmaceutical and Biomedical Analysis
https://read.qxmd.com/read/30877930/seventeen-o-acetylated-n-glycans-and-six-o-acetylation-sites-of-myozyme-identified-using-liquid-chromatography-tandem-mass-spectrometry
#4
Heajin Park, Seungkwan You, Jihye Kim, Wooseok Kim, Jonghye Do, Yeonjoo Jang, Donghwi Kim, Junmyoung Lee, Jongkwan Ha, Doo-Byoung Oh, Jae Il Kim, Ha Hyung Kim
O-acetylated sialic acid (SA) attached to the N-glycans of therapeutic glycoproteins reportedly inhibit sialidase activity, increase protein half-life, decrease protein antigenicity, and stabilize protein conformation. Recombinant human acid α-glucosidase (Myozyme) is the only drug approved by the United States Food and Drug Administration for the treatment of Pompe disease. In this study, unreported N-glycans containing O-acetylated SA in Myozyme and the relative quantities of total glycans were investigated using liquid chromatography (LC)-electrospray ionization (ESI)-high-energy collisional dissociation (HCD) tandem mass spectrometry (MS/MS)...
March 7, 2019: Journal of Pharmaceutical and Biomedical Analysis
https://read.qxmd.com/read/30877879/esi-tof-ms-analysis-of-complexes-formed-between-quercetin-and-five-metal-ions-in-hot-water-and-a-study-into-their-dna-cleavage-activity
#5
Han Manman, Cai Weilan, Li Zhimin, Peng Liang, He Lixia, Chen Min
Quercetin is a flavonoid compound widely found in vegetables, fruits, and medicinal plants. It has carbonyl and phenolic hydroxyl groups in its structure that can easily form complexes with metal ions. In this study, we reacted quercetin in water at 95 °C with five metal trace elements commonly found in plants, namely calcium, magnesium, zinc, iron(III), and copper. Each supernatant was then examined by electrospray ionization-time-of-flight mass spectrometry (ESI-TOF MS). The results showed that quercetin can form complexes with Ca2+ , Mg2+ , Zn2+ , and Cu2+ in ratios of 2:1, 3:1, and 3:2...
March 4, 2019: Journal of Inorganic Biochemistry
https://read.qxmd.com/read/30876839/proteomic-analysis-of-tear-fluid-reveals-disease-specific-patterns-in-patients-with-parkinson-s-disease-a-pilot-study
#6
Matthias Boerger, Sebastian Funke, Andreas Leha, Anna-Elisa Roser, Ann-Katrin Wuestemann, Fabian Maass, Mathias Bähr, Franz Grus, Paul Lingor
BACKGROUND: The diagnosis of Parkinson's disease (PD) is still challenging and biomarkers could contribute to an improved diagnostic accuracy. Tear fluid (TF) is an easily accessible body fluid reflecting pathophysiological changes in systemic and ocular diseases and is already used as a biomarker source for several ophthalmological disorders. Here, we analyzed the TF of patients with PD and controls (CTR) to describe disease-related changes in TF and identify putative biomarkers for the diagnosis of PD...
March 6, 2019: Parkinsonism & related Disorders
https://read.qxmd.com/read/30876588/liquid-chromatography-tandem-mass-spectrometry-method-for-simultaneous-determination-of-three-n-7-guanine-adducts-of-the-active-epoxides-of-prodrug-treosulfan-in-dna-in-vitro
#7
Michał Romański, Konrad Rotecki, Bartosz Nowicki, Artur Teżyk, Franciszek K Główka
Prodrug treosulfan undergoes a pH and temperature-dependent activation to the monoepoxide intermediate (EBDM) and (2S,3S)-1,2:3,4-diepoxybutane (DEB). The latter DNA cross-linker is presently believed to mainly account for the pharmacological action of treosulfan. However, neither respective monoadducts nor cross-links have been isolated from treosulfan-treated DNA, and the exact alkylation mechanism of the treosulfan epoxides is unclear. In this paper, liquid chromatography method with tandem mass spectrometry detection (LC-MS/MS) for simultaneous determination of the N-7-guanine adducts of EBDM and DEB - (2'S,3'S)-N-7-(2'3'-dihydroxy-4'-methylsulfonyloxybut-1'-yl)guanine (HMSBG), N-7-(2',3',4'-trihydroxybut-1'-yl)guanine (THBG), and 1,4-bis(N-7-guanyl)butane-2,3-diol cross-link (bis-N7G-BD) - in calf-thymus DNA has been developed and validated for the first time...
June 1, 2019: Talanta
https://read.qxmd.com/read/30876579/automated-solid-phase-extraction-and-electrospray-chip-based-on-programmatic-pneumatic-micro-valves
#8
Xiahong Wei, Yinyin Hao, Xueying Huang, Yijun Hu, Bo Xiong
Microfluidic chips coupled with electrospray ionization (ESI) mass spectrometry (MS) is an analytical platform with high detection throughputs and low sample consumptions. However, its applications in probing real samples are limited by the absence of reliable on-chip sample pretreatments, which are indispensable due to both the low contents of analytes and the poor salt tolerance of ESI MS. Herein, we propose an automated extraction and ESI chip (AEEC), consisting of a solid phase extraction (SPE) zone, seven on-chip pneumatic micro-valves, a monolithic ESI nozzle, and other components, to implement on-chip SPE prior to on-line ESI for analytes...
June 1, 2019: Talanta
https://read.qxmd.com/read/30876566/combination-of-electrospray-deposition-technology-of-tio-2-nanoparticles-and-maldi-fticr-msi-for-identification-of-fingerprint-morphology-and-latent-components
#9
Hui Yang, Shilei Li, Qian Zhang, Zhenpeng Wang, Na Li, Chao Han, Qing Huo, Zhenwen Zhao
In fingerprint recognition, besides the physical shape information afforded by fingerprint enhancement techniques (FET), in recent years, more and more efforts are focused on researching the chemical composition of a fingerprint residue. In this work, electrospray deposition method was elaborately used to softly and homogenously deposit the physical enhancers of FET, TiO2 nanoparticles (TiO2 NPs), onto fingerprints. The results showed that this type of deposition was nondestructive to the fingerprint morphology and provided the physical shape information containing all level features...
June 1, 2019: Talanta
https://read.qxmd.com/read/30876551/assessing-mixtures-of-supercharging-agents-to-increase-the-abundance-of-a-specific-charge-state-of-neuromedin-u
#10
Yannick Van Wanseele, Jana Bongaerts, Karen Segers, Johan Viaene, Dimitri De Bundel, Yvan Vander Heyden, Ilse Smolders, Ann Van Eeckhaut
With increasing evidence of the important role of peptides in pathophysiological processes, a trend towards the development of highly sensitive bioanalytical methods is ongoing. Inherent to the electrospray ionization process of peptides and proteins is the production of multiple charge states which may hamper proper and sensitive method development. Supercharging agents allow modifying the maximal charge state and the corresponding distribution of charges, thereby potentially increasing the number of ions reaching the detector in selected reaction monitoring mode...
June 1, 2019: Talanta
https://read.qxmd.com/read/30875441/the-triacylglycerol-profile-of-oil-bodies-and-oil-extracted-from-argania-spinosa-using-the-uplc-along-with-the-electrospray-ionization-quadrupole-time-of-flight-mass-spectrometry-lc-q-tof-ms
#11
Farah Zaaboul, Chen Cao, Husnain Raza, Zhao Zheng Jun, Yong Jiang Xu, Yuan Fa Liu
The triacylglycerol (TAG) matrix of argan oil (AO) bodies (AOB) along with the TAGs of AO extracted from the same kernels using an organic solvent, were identified and quantified using the ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry. Generally, both samples showed a similar TAGs profile but AO found to have three extra TAGs in low amount. In total 23 and 26 different TAGs were identified in AOBs and AO, respectively. The most abundant TAGs were OOL, POO, OOO, and POL in both samples...
March 15, 2019: Journal of Food Science
https://read.qxmd.com/read/30875096/impaired-clearance-of-sunitinib-leads-to-metabolic-disorders-and-hepatotoxicity
#12
Qi Zhao, Ting Zhang, Xue-Rong Xiao, Jian-Feng Huang, Yan Wang, Frank J Gonzalez, Fei Li
BACKGROUND AND PURPOSE: Sunitinib is a small molecule tyrosine kinase inhibitor associated with hepatotoxicity. The mechanisms of its toxicity are still unclear. EXPERIMENTAL APPROACH: In the present study, mice were treated with 60 mg kg-1, 150 mg kg-1, and 450 mg kg-1 sunitinib to evaluate sunitinib hepatotoxicity. Sunitinib metabolites and endogenous metabolites in liver, serum, feces, and urine were analyzed using ultra-performance liquid chromatography electrospray ionization quadrupole time-of-flight mass spectrometry-based metabolomics...
March 15, 2019: British Journal of Pharmacology
https://read.qxmd.com/read/30873865/optimization-of-column-chromatography-technique-for-the-isolation-of-tetrandrine-from-cyclea-peltata-and-lc-esi-ms-based-quantification-and-validation-of-the-method
#13
Bhagya N, Chandrashekar K R
Reverse phase column chromatography technique was employed to isolate tetrandrine from methanolic extract of Cyclea peltata roots. Tetrandrine was efficiently isolated using 0.02% aqueous diethylamine and methanol (25:75, v/v) as mobile phase with a purity of 98.63%. Compound characterisation was achieved using high-performance liquid chromatography coupled with electrospray ionization mass spectrometry and other spectroscopic methods. In addition, quantification of tetrandrine and validation of the method was carried out following International Conference on Harmonisation guidelines...
March 15, 2019: Natural Product Research
https://read.qxmd.com/read/30872168/in-vivo-and-in-vitro-metabolism-and-pharmacokinetics-of-cholinesterase-inhibitor-deoxyvasicine-from-aerial-parts-of-peganum-harmala-linn-in-rats-via-uplc-esi-qtof-ms-and-uplc-esi-ms-ms
#14
Gang Deng, Wei Liu, Chao Ma, Xiaojuan Rong, Yunpeng Zhang, Youxu Wang, Chao Wu, Ning Cao, Wenzheng Ding, Huida Guan, Xuemei Cheng, Changhong Wang
ETHNOPHARMACOLOGICAL RELEVANCE: Aerial parts of Peganum harmala Linn are a Uighur traditional medicinal herb in China used to treat amnesia, bronchial asthma, and cough. Deoxyvasicine (DVAS), a potent cholinesterase inhibitor exhibiting anti-senile dementia activity, is one of the chief active ingredients in aerial parts of P. harmala and plays a key role in mediating the pharmacological effects of P. harmala. However, the metabolic profiling and in vivo pharmacokinetic characteristics of DVAS still remain unknown...
March 11, 2019: Journal of Ethnopharmacology
https://read.qxmd.com/read/30870692/identification-and-analysis-of-components-in-shen-fu-shu-granule-extract-and-in-rat-plasma-after-oral-administration-by-uplc-esi-q-tof-ms
#15
Ying Chen, Suhua Zhang, Shanshan Wei, Yao Li, Wenqun Li, Miao Yan, Yang Deng, Bikui Zhang, Hualin Cai
BACKGROUND AND OBJECTIVES: Shen-Fu-Shu granule is traditional Chinese herb formula for acute and chronic renal failure. This work was aimed to identify the compounds in Shen-Fu-Shu granule extract and absorbed compounds in rat plasma following oral administration of Shen-Fu-Shu granule. METHODS: A high-resolution and high-sensitivity ultra-performance liquid chromatography with electrospray ionization quadrupole time-of-flight tandem mass spectrometry in positive and negative ion mode were established...
March 6, 2019: Journal of Pharmaceutical and Biomedical Analysis
https://read.qxmd.com/read/30870504/ultra-performance-hydrophilic-interaction-liquid-chromatography-coupled-with-tandem-mass-spectrometry-for-simultaneous-determination-of-allopurinol-oxypurinol-and-lesinurad-in-rat-plasma-application-to-pharmacokinetic-study-in-rats
#16
Muzaffar Iqbal, Essam Ezzeldin, Rashed Naji Herqash, Ozair Alam
A fixed dose combination of lesinurad and allopurinol has been recently approved by USFDA and EMA for treatment of gout-associated hyperuricemia in patients who have not achieved target serum uric acid levels with allopurinol alone. In this study, an ultra-performance hydrophilic interaction liquid chromatography (UPHILIC) coupled with tandem mass spectrometry method was developed and validated for simultaneous determination of allopurinol, oxypurinol and lesinurad in rat plasma. Liquid liquid extraction using ethyl acetate as extracting agent was used for samples extraction procedure...
2019: PloS One
https://read.qxmd.com/read/30869513/integrated-synthesis-of-gold-nanoparticles-coated-with-polyoxometalate-clusters
#17
Sergio Martín, Yohei Takashima, Chang-Gen Lin, Yu-Fei Song, Haralampos N Miras, Leroy Cronin
Polyoxometalates (POMs) have been found to be good end-capping ligands for gold nanoparticles (AuNPs). Herein, we introduce a new synthetic method to synthesize gold nanoparticle-POM hybrids by heating a solution of AuNO3 (PMe3 ) in acetonitrile in the presence of appropriate POM species with tetrabutylammonium (TBA) as a countercation at 120 °C in a microwave. This method allowed us to produce POM-capped AuNPs without over-reduction of the solution causing decomposition or reorganization of the POMs. Analysis of the resulting material by transmission electron microscopy showed that the POM's size, charge, and functionality are key factors controlling the resulting POM-AuNP hybrid structure...
March 14, 2019: Inorganic Chemistry
https://read.qxmd.com/read/30868582/changes-in-the-profiling-of-bioactive-components-with-the-roasting-process-in-lycium-chinense-leaves-and-the-anti-obesity-effect-of-its-bio-accessible-fractions
#18
Eun-Hye Choi, Da-Yeon Lee, Hee-Sook Park, Soon-Mi Shim
BACKGROUND: The present study aimed to investigate the profiles of bioactive components in roasted Lycium chinense leaves (LCL) and its in vitro anti-obesity activity after digestion processes. RESULTS: Chlorogenic acid, kaempferol-3-sophoroside-7-glucoside, kaempferol-3-sophoroside, and kaempferol-3-glucoside were discovered as bioactive components in various ratios of EtOH extract in LCL by using ultra-performance liquid chromatography-electrospray ionization- mass spectrophotometry (UPLC-ESI-MS)...
March 14, 2019: Journal of the Science of Food and Agriculture
https://read.qxmd.com/read/30866469/defining-metabolic-rewiring-in-lung-squamous-cell-carcinoma
#19
Rachel Paes de Araújo, Natália Bertoni, Ana L Seneda, Tainara F Felix, Márcio Carvalho, Keir E Lewis, Érica N Hasimoto, Manfred Beckmann, Sandra A Drigo, Patricia P Reis, Luis A J Mur
Metabolomics based on untargeted flow infusion electrospray ionization high-resolution mass spectrometry (FIE-HRMS) can provide a snap-shot of metabolism in living cells. Lung Squamous Cell Carcinoma (SCC) is one of the predominant subtypes of Non-Small Cell Lung Cancers (NSCLCs), which usually shows a poor prognosis. We analysed lung SCC samples and matched histologically normal lung tissues from eight patients. Metabolites were profiled by FIE-HRMS and assessed using t -test and principal component analysis (PCA)...
March 7, 2019: Metabolites
https://read.qxmd.com/read/30864788/carboxamidate-ligand-noninnocence-in-proton-coupled-electron-transfer
#20
Caitilín McManus, Prasenjit Mondal, Marta Lovisari, Brendan Twamley, Aidan R McDonald
Recent breakthroughs have brought into question the innocence (or not) of carboxamidate donor ligands in the reactivity of high-valent oxidants. To test the reactivity properties of high-valent carboxamidate complexes, [NiII (t Bu-terpy)(L)] (1, t Bu-terpy = 4,4',4''-tri- tert-butyl-2,2';6',2″-terpyridine; L = N, N'-(2,6-dimethylphenyl)-2,6-pyridinedicarboxamidate) was prepared and converted to [NiIII (t Bu-terpy)(L)]+ (2) using ceric ammonium nitrate. 2 was characterized using electronic absorption and electron paramagnetic resonance spectroscopies and electrospray ionization mass spectrometry...
March 13, 2019: Inorganic Chemistry
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