keyword
MENU ▼
Read by QxMD icon Read
search

Ultra High Dilution

keyword
https://read.qxmd.com/read/30747180/rapid-detection-of-hypnotics-using-surface-enhanced-raman-scattering-based-on-gold-nanoparticle-co-aggregation-in-a-wet-system
#1
Hiroki Segawa, Takao Fukuoka, Tamitake Itoh, Yuichi Imai, Yuko T Iwata, Tadashi Yamamuro, Kenji Kuwayama, Kenji Tsujikawa, Tatsuyuki Kanamori, Hiroyuki Inoue
Sensitive detection of drugs using a method with high qualification capability is important for forensic drug analysis. Vibrational spectroscopy is a powerful screening technique because it can provide detailed structural information of the compounds included in samples with simple experimental protocols. Among various spectroscopic techniques, surface enhanced Raman scattering (SERS) spectroscopy has attracted enormous attention owing to its ultra-high sensitivity. In this study, we developed a method for rapid detection of hypnotics using SERS with gold nanoparticle co-aggregation in a wet system...
February 12, 2019: Analyst
https://read.qxmd.com/read/30738340/development-of-a-validated-method-for-the-qualitative-and-quantitative-analysis-of-cannabinoids-in-plant-biomass-and-medicinal-cannabis-resin-extracts-obtained-by-super-critical-fluid-extraction
#2
Aaron C Elkins, Myrna A Deseo, Simone Rochfort, Vilnis Ezernieks, German Spangenberg
The social push for the therapeutic use of cannabis extracts has increased significantly over recent years. Cannabis is being used for treatment for conditions such as epilepsy, cancer and pain management. There are a range of medicinal cannabis products available, but the use of cannabis resin obtained by super critical fluid extraction, often diluted in oil, is becoming increasingly more prominent. Much of the research on cannabis has focused on plant biomass or the final therapeutic product with a concerning lack of information on the intermediate resin...
January 30, 2019: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://read.qxmd.com/read/30733886/fast-simultaneous-determination-of-eight-sudan-dyes-in-chili-oil-by-ultra-high-performance-supercritical-fluid-chromatography
#3
Yunjia Yang, Jing Zhang, Jie Yin, Yi Yang
A rapid and simple ultra-high-performance supercritical fluid chromatography (UHPSFC) with photodiode array (PDA) method was developed and validated for simultaneous determination of eight Sudan dyes in chili oil. In particular, a pair of isomer, Sudan red B and Sudan IV, was included in the analysis. After being diluted with dichloromethane, the analytes were separated on an Acquity UPC2 HSS C18 SB column with gradient elution using CO2 as the mobile phase and acetonitrile/methanol (v/v, 45/55, containing 0...
2019: Journal of Analytical Methods in Chemistry
https://read.qxmd.com/read/30693714/-non-targeted-screening-and-determination-of-steviol-glycosides-in-chinese-liquor-and-beverages-by-ultra-high-performance-liquid-chromatography-quadrupole-orbitrap-mass-spectrometry
#4
Feng Feng, Weiming Li, Yan Sun, Feng Zhang
A method for simultaneous screening and determination of steviol glycosides in Chinese liquor and beverages by hydrophilic interaction ultra-high performance liquid chromatography-quadrupole/Orbitrap high resolution mass spectrometry (HILIC-UHPLC-Q/Orbitrap HRMS) was developed. In addition, the MS fragment path ways of steviol glycosides were characterized. The sample was diluted and filtrated before analysis, separated by a Waters Xbridge Amide column (150 mm×4.6 mm, 3.5 μm), and determined via UHPLC-Q/Orbitrap HRMS...
January 8, 2019: Se Pu, Chinese Journal of Chromatography
https://read.qxmd.com/read/30660808/rapid-hydrolysis-free-dilute-and-shoot-method-for-the-determination-of-buprenorphine-norbuprenorphine-and-their-glucuronides-in-urine-samples-using-uhplc-ms-ms
#5
Marco Agostini, Caterina Renzoni, Elisabetta Pierini, Maurizio Piergiovanni, Veronica Termopoli, Giorgio Famiglini, Pierangela Palma, Achille Cappiello
Buprenorphine and its metabolites are routinely monitored to assess patient compliance with drug detoxification programs or as pain killers. A rapid method for the simultaneous analysis of buprenorphine, norbuprenorphine, and glucuronides in urine using ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) was developed. Urine samples were diluted in water containing formic acid 0.1% and directly injected into the UHPLC-MS/MS system without any sample pretreatment. Quality control (QC) samples, prepared using 20 different urine matrices, fortified at 3 concentration levels, were quantified using four deuterated internal standards...
January 11, 2019: Journal of Pharmaceutical and Biomedical Analysis
https://read.qxmd.com/read/30638711/simultaneous-determination-of-the-quaternary-ammonium-pesticides-paraquat-diquat-chlormequat-and-mepiquat-in-barley-and-wheat-using-a-modified-quick-polar-pesticides-method-diluted-standard-addition-calibration-and-hydrophilic-interaction-liquid-chromatography
#6
Janice Z Francesquett, Tiele M Rizzetti, Tito R S Cadaval, Osmar D Prestes, Martha B Adaime, Renato Zanella
In this study, a modified Quick Polar Pesticides (QuPPe) method, optimized by a central composite design, was developed to determine quaternary ammonium pesticides (QUATs) residues in barley and wheat by ultra-high-performance liquid chromatographic tandem mass spectrometry (UHPLC-MS/MS) using a hydrophilic interaction chromatography (HILIC) column. Considering the high polarity of these compounds, special conditions of sample preparation and analysis are required. Different mobile phases, extraction procedure and clean-up were evaluated...
December 28, 2018: Journal of Chromatography. A
https://read.qxmd.com/read/30564584/pharmacokinetics-and-pharmacodynamics-of-an-oral-formulation-of-apixaban-in-horses-after-oral-and-intravenous-administration
#7
Priscila B S Serpa, Marjory B Brooks, Thomas Divers, Sally Ness, Ingvild Birschmann, Mark G Papich, Tracy Stokol
Horses with inflammatory and infectious disorders are often treated with injectable heparin anticoagulants to prevent thrombotic complications. In humans, a new class of direct oral acting anticoagulants (DOAC) appear as effective as heparin, while eliminating the need for daily injections. Our study in horses evaluated apixaban, a newly approved DOAC for human thromboprophylaxis targeting activated factor X (Xa). Our goals were to: (1) Determine pharmacokinetics and pharmacodynamics of apixaban after oral (PO) and intravenous (IV) administration in horses; (2) Detect any inhibitory effects of apixaban on ex vivo Equid herpesvirus type 1 (EHV-1)-induced platelet activation, and (3) Compare an anti-Xa bioactivity assay with ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) for measuring apixaban concentrations...
2018: Frontiers in Veterinary Science
https://read.qxmd.com/read/30559375/isotope-dilution-mass-spectrometry-for-exact-quantification-of-noncanonical-dna-nucleosides
#8
Franziska R Traube, Sarah Schiffers, Katharina Iwan, Stefanie Kellner, Fabio Spada, Markus Müller, Thomas Carell
DNA contains not only canonical nucleotides but also a variety of modifications of the bases. In particular, cytosine and adenine are frequently modified. Determination of the exact quantity of these noncanonical bases can contribute to the characterization of the state of a biological system, e.g., determination of disease or developmental processes, and is therefore extremely important. Here, we present a workflow that includes detailed description of critical sample preparation steps and important aspects of mass spectrometry analysis and validation...
December 17, 2018: Nature Protocols
https://read.qxmd.com/read/30536941/analytical-validation-of-a-conventional-cardiac-troponin-i-assay-for-dogs-and-cats
#9
Rebecca Langhorn, Jacob D Yrfelt, Claus S Stjernegaard, Liselotte B Christiansen, Lisbeth H Olsen, Lise N Nielsen
BACKGROUND: Cardiac troponins are gold-standard biomarkers of myocardial injury. There is a need for validation of assays with higher availability and lower costs in veterinary medicine. OBJECTIVES: The primary aim of the present study was to perform an analytical validation of the IMMULITE 2000 TnI assay for use in dogs and cats. A secondary aim was to evaluate its agreement with the previously validated and sensitive Siemens ADVIA Centaur TnI-Ultra assay. METHODS: Intra- and inter-assay variation, detection limits, the linearity under dilution, and a sample addition study (modified spike-and-recovery analysis) were investigated to assess analytical performance in 15 canine and 15 feline serum samples...
December 11, 2018: Veterinary Clinical Pathology
https://read.qxmd.com/read/30536899/highly-sensitive-spectrofluorimetric-method-for-rapid-determination-of-orciprenaline-in-biological-fluids-and-pharmaceuticals
#10
F A Ibrahim, M E Fathy, H M Elmansi
Orciprenaline sulphate (ORP) is a direct-acting sympathomimetic with mainly beta-adrenoceptor stimulant activity. It is used as a bronchodilator in the management of reversible airway obstruction. For the first time, a rapid highly sensitive spectrofluorimetric method is described that is relied on measuring the fluorescence spectra of ORP at acidic pH and without addition of any chemical reagents. The relative fluorescence intensity was measured at 310 nm and after excitation at 224 nm. ORP native fluorescence was calibrated in both water and acetonitrile as diluting solvents...
December 11, 2018: Luminescence: the Journal of Biological and Chemical Luminescence
https://read.qxmd.com/read/30484677/the-quantitation-of-7beta-hydroxy-epiandrosterone-in-the-plasma-and-seminal-plasma-of-men-with-different-degrees-of-fertility
#11
J Vitku, L Kolatorova, C Ricco, C Ferroud, O Hennebert, T Skodova, J Heracek, L Starka
7beta-hydroxy-epiandrosterone (7beta-OH-EpiA) is an endogenous androgen metabolite that has been shown to exert neuroprotective, anti-inflammatory and anti-estrogenic effects. However, to the best of our knowledge no information is available about this androgen steroid in relation to sperm quality. We analyzed 7beta-OH-EpiA in plasma and seminal plasma using a newly developed isotope dilution ultra-high performance liquid chromatography - mass spectrometry method. Validation met the requirements of FDA guidelines...
November 28, 2018: Physiological Research
https://read.qxmd.com/read/30481391/simultaneous-detection-of-multiple-hydroxylated-polychlorinated-biphenyls-from-biological-samples-using-ultra-high-performance-liquid-chromatography-isotope-dilution-tandem-mass-spectrometry
#12
Yibin Zheng, Delei Cai, Baifen Huang, Jianlong Han, Qing Chen, Jingshun Zhang, Jie Zhang, Xiaofeng Wang, Haitao Shen
In this paper, we established a method for the separation and detection of nine hydroxylated polychlorinated biphenyls in whole blood and urine samples using UPLC coupled with electrospray negative ionization tandem-mass spectrometry. Clean-up procedures involved a filtration step, and optimization involved a pretreatment step consisting of a simple liquid-liquid extraction, using hydrated silica-gel chromatography (5%). Nine hydroxylated polychlorinated biphenyls were separated on a UPLC HSS T3 column using a gradient elution program of 2 mmol ammonium formate aqueous solution (A), and methanol (B)...
November 27, 2018: Journal of Separation Science
https://read.qxmd.com/read/30430926/isolation-molecular-identification-and-characterization-of-a-unique-toxic-cyanobacterium-microcystis-sp-found-in-hunan-province-china
#13
Pin Liu, Jia Wei, Kun Yang, Isaac Yaw Massey, Jian Guo, Chengcheng Zhang, Fei Yang
Global proliferation of cyanobacterial blooms associated with climate change and eutrophication constitutes a serious environmental threat. In Hunan Province a freshwater pond located in Changsha City was found to contain high concentrations of cyanobacteria, however, the characteristics of these cyanobacteria at present are not known. This study thus aimed to isolate, identify the most common bloom-forming cyanobacteria in this region and determine the toxigenic characteristics of the predominant cyanobacteria...
November 15, 2018: Journal of Toxicology and Environmental Health. Part A
https://read.qxmd.com/read/30409968/electrochemically-mediated-selective-capture-of-heavy-metal-chromium-and-arsenic-oxyanions-from-water
#14
Xiao Su, Akihiro Kushima, Cameron Halliday, Jian Zhou, Ju Li, T Alan Hatton
The removal of highly toxic, ultra-dilute contaminants of concern has been a primary challenge for clean water technologies. Chromium and arsenic are among the most prevalent heavy metal pollutants in urban and agricultural waters, with current separation processes having severe limitations due to lack of molecular selectivity. Here, we report redox-active metallopolymer electrodes for the selective electrochemical removal of chromium and arsenic. An uptake greater than 100 mg Cr/g adsorbent can be achieved electrochemically, with a 99% reversible working capacity, with the bound chromium ions released in the less harmful trivalent form...
November 8, 2018: Nature Communications
https://read.qxmd.com/read/30407186/ultra-small-angle-x-ray-photon-correlation-spectroscopy-using-the-eiger-detector
#15
T Zinn, A Homs, L Sharpnack, G Tinti, E Fröjdh, P A Douissard, M Kocsis, J Möller, Y Chushkin, T Narayanan
Successful implementation of the single-photon-counting Eiger 500k pixel array detector for sub-millisecond X-ray photon correlation spectroscopy (XPCS) measurements in the ultra-small-angle scattering region is reported. The performance is demonstrated by measuring the dynamics of dilute silica colloids in aqueous solvents when the detector is operated at different counter depths, 4, 8 and 12 bit. In the fastest mode involving 4 bit parallel readout, a stable frame rate of 22 kHz is obtained that enabled measurement of intensity-intensity autocorrelation functions with good statistics down to the 50 µs range for a sample with sufficient scattering power...
November 1, 2018: Journal of Synchrotron Radiation
https://read.qxmd.com/read/30371841/quantitative-analysis-of-fentanyl-and-six-fentanyl-analogs-in-postmortem-specimens-by-uhplc-ms-ms
#16
Joseph H Kahl, Jennifer Gonyea, Susan M Humphrey, George W Hime, Diane M Boland
Since 2013, opioid-related deaths have increased in Miami-Dade County, FL due to fentanyl and fentanyl analogs in the local heroin supply. From 2014 to 2015, a near 600% increase in fentanyl and fentanyl analog-related deaths was observed, followed by another 200% increase in 2016. In addition to fentanyl, six fentanyl analogs were identified in this time period: β-hydroxythiofentanyl, acetyl fentanyl, furanyl fentanyl, carfentanil, butyryl fentanyl and para-fluoroisobutyryl fentanyl. As a result, an analytical method to quantify these compounds in postmortem biological fluids and tissues using solid-phase extraction with analysis by ultra high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS-MS) was developed and validated...
October 1, 2018: Journal of Analytical Toxicology
https://read.qxmd.com/read/30366208/a-direct-sensitive-and-efficient-method-for-determination-of-alpha-fluoro-beta-alanine-in-urine-evaluating-the-influence-of-magnesium-isoglycyrrhizinate-on-excretion-in-rat-model
#17
Zhipeng Wang, Yang Yang, Feng Zhang, Mingming Li, Jing Chen, Huan Man, Wei Jiang, Rui Zhang, Shouhong Gao, Wansheng Chen
Alpha-fluoro-beta-alanine (FBAL), the final metabolite of capecitabine, is a toxic compound excreting with urine. Magnesium isoglycyrrhizinate injection is a traditional Chinese medicine prescribed with capecitabine as a hepatoprotective agent. The purposes of this study are to develop an ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method for direct, efficient and sensitive determination of FBAL in urine and explore the influence of magnesium isoglycyrrhizinate on the excretion of FBAL in rat model...
October 18, 2018: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://read.qxmd.com/read/30296508/substitution-therapy-with-amphetamine-isotherapic-attenuates-amphetamine-toxicological-aspects-of-addiction
#18
Hecson J Segat, Vinícia G Metz, Higor Z Rosa, Verônica T Dias, Raquel C S Barcelos, Geisa S Dolci, Marilise E Burger
INTRODUCTION: amphetamine (AMPH) is related to development of addiction, anxiety-like behaviors and impairments of memory after chronic use. In the current experiment, an ultra-high dilution (10-24 mg/mL) of AMPH was used, consisting of the AMPH isotherapic (AMPH-ISO), which can be used as a replacement therapy to treat AMPH addiction. AIM: To verify the influence of AMPH-ISO on toxicological aspects of AMPH addiction. METHODS: Rats received d,l-AMPH (4...
October 5, 2018: Neuroscience Letters
https://read.qxmd.com/read/30293592/a-stable-method-for-routine-analysis-of-oxylipins-from-dried-blood-spots-using-ultra-high-performance-liquid-chromatography-tandem-mass-spectrometry
#19
Erandi Hewawasam, Ge Liu, David W Jeffery, Beverly S Muhlhausler, Robert A Gibson
Oxylipins are biologically important lipid mediators that are derived enzymatically from polyunsaturated fatty acids (PUFA) and have a major role in regulating inflammatory processes. The currently available methods for measuring oxylipins from human biological samples have limitations, which restricts their use in large studies. We have developed a novel method for measuring 21 oxylipins from dried blood spot (DBS) using ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) and stable isotope dilution analysis...
October 2018: Prostaglandins, Leukotrienes, and Essential Fatty Acids
https://read.qxmd.com/read/30290377/biological-actions-electrical-conductance-and-silicon-containing-microparticles-of-arsenicum-album-prepared-in-plastic-and-glass-vials
#20
Luciane Costa Dalboni, Cideli de Paula Coelho, Renata Rossettini Palombo Pedro, Michelle Sanchez Correia, Fabiana Rodrigues de Santana, Thayná Neves Cardoso, Sandra Augusta G Pinto, Anuska M Alvares-Saraiva, Maristela Dutra-Correa, Giovani B Peres, Carla Holandino, André Rossi, Amarilys de Toledo César, Silvia Waisse, Leoni Villano Bonamin
INTRODUCTION:  According to the "silica hypothesis" formulated to explain homeopathy, the information of starting materials would be transferred to cells by silica nanoparticles detached from the glassware walls by serial dilution and agitation through epitaxy. We compared the biological activity, electrical current and silicon microparticle content (by means of scanning electron microscopy/energy-dispersive X-ray spectroscopy) of high dilutions (HDs) of arsenic prepared in plastic and glass vials to investigate the role of silica in their biological effects in vitro...
October 5, 2018: Homeopathy: the Journal of the Faculty of Homeopathy
keyword
keyword
166611
1
2
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"