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Liquid Biopsies for Pancreatic Cancer: A Step Towards Early Detection
Published in Surinder K. Batra, Moorthy P. Ponnusamy, Gene Regulation and Therapeutics for Cancer, 2021
Joseph Carmicheal, Rahat Jahan, Koelina Ganguly, Ashu Shah, Sukhwinder Kaur
Generally, Gas Chromatography-Mass Spectrometry (GC-MS), Liquid Chromatography-Mass Spectrometry (LC-MS), Capillary Electrophorese-Mass Spectrometry (CE-MS), Fourier Transform Ion Cyclotron Resonance-Mass Spectrometry (FTICR-MS), Nuclear Magnetic Resonance (NMR) and High Resolution Magic Angle Spinning Nuclear Magnetic Spectroscopy (HR-MAS-NMR) are used for metabolic profiling from biological specimens. These techniques have their own advantages/ disadvantages but data acquired by each separate modality complement one another [42, 43]. Also, due to the technical difficulties, hydrophilic and hydrophobic metabolites have not yet been able to be analyzed using a single technique. Thus, for obtaining a robust and global metabolite profile of the patient and in order to discern the disease versus normal states, a combination of various analytical techniques is used [43]. Recent advances in the field have enabled metabolites to be visualized spatially within biological samples using imaging mass spectrometry [44].
Characterization of Phyto-Constituents
Published in Rohit Dutt, Anil K. Sharma, Raj K. Keservani, Vandana Garg, Promising Drug Molecules of Natural Origin, 2020
Himangini, Faizana Fayaz, Anjali
The hyphenated technique has become revolutionary change in the identification, characterization, and quantization of herbal drugs. One of the best methods developed by combining liquid chromatography and infrared spectroscopy is known as LC-IR. LC-IR predicts the peaks of functional groups in mid-IR region which makes structure elucidation helpful. But detection technique of IR is much slower than MS or NMR. Two big tools in series may be used in these techniques are flow cell method and solvent elimination methods. Liquid chromatography-mass spectrometry (LC-MS) combines liquid chromatography with the capabilities of MS. LC-MS has very high sensitivity and selectivity for identification of mixture of separated components.
Phytochemical and Bioactive Potential of Melastoma malabathricum: an Important Medicinal Herb
Published in V. R. Mohan, A. Doss, P. S. Tresina, Ethnomedicinal Plants with Therapeutic Properties, 2019
Gas chromatography-mass spectrometry (GC–MS) is an analytical method that combines the features of gas chromatography and mass spectrometry to identify different substances within a test sample applications of GC–MS include drug detection, fire investigation, environmental analysis, explosives investigation, and identification of unknown samples, including that of material samples obtained from planet Mars during probe missions as early as the 1970s. GC–MS can also be used in airport security to detect substances in luggage or on human beings. Additionally, it can identify trace elements in materials that were previously thought to have disintegrated beyond identification. Like liquid chromatography–mass spectrometry, it allows analysis and detection even for the tiny amounts of a substance (David Sparkman et al., 2011).
Soyasaponin I alleviates hypertensive intracerebral hemorrhage by inhibiting the renin–angiotensin–aldosterone system
Published in Clinical and Experimental Hypertension, 2023
Wei Li, Shao-Guang Li, Lan Li, Li-Jian Yang, Zeng-Shi Li, Xi Li, An-Yuan Ye, Yang Xiong, Yi Zhang, Yuan-Yuan Xiong
Samples were first dissolved and extracted using methanol. Equal amounts were taken from all samples and then mixed as quality control (QC) samples. Liquid chromatography–mass spectrometry (LC–MS) analysis was performed on a high-performance liquid chromatograph (#AB ExionLC, AB Sciex, USA) and a high-resolution mass spectrometer (#QE, ThermoFisher, USA). The chromatographic column was ACQUITY UPLC BEH C18 (100 mm × 2.1 mm, 1.7 μm, Waters, USA) with the column temperature set at 40°C. The mobile phase A was water (containing 0.1% formic acid), the mobile phase B was acetonitrile (containing 0.1% formic acid), and the flow rate was set at 0.35 mL/min with an injection volume of 5 μL. The gradient elution program was as follows: 0 min A:B = 95:5; 1.5 min A:B = 95:5; 3 min A:B = 70:30; 7 min A:B = 40:60; 9 min A:B = 10:90; and 11 min A:B = 10:90. The MS signal acquisition was performed in positive and negative ion scan mode, and the MS parameters were set as follows: spray voltage, 3500 V; capillary temperature, 320°C; probe heater temperature, 350°C; sheath gas flow rate, 40 Arb; auxillary gas flow rate, 10 Arb; S-lens RF level, 50; mass range, 100–1000 m/z. Finally, metabolomic analysis of LC–MS data was commissioned from Shanghai Lu-Ming Biotech Co., Ltd.
Accuracy of substance exposure history in patients attending emergency departments after substance misuse; a comparison with biological sample analysis
Published in Clinical Toxicology, 2023
Ishita Virmani, Alberto Oteo, Michael Dunn, Daniel Vidler, Clair Roper, Jane Officer, Gareth Hardy, Paul I. Dargan, Michael Eddleston, Jamie G. Cooper, Simon L. Hill, Rebecca Macfarlane, Liza Keating, Mark Haden, Simon Hudson, Simon H. L. Thomas
Toxicity resulting from substance misuse (sometimes called recreational drug use/misuse) is a common reason for emergency department (ED) presentations and hospital admissions [1,2]. Knowledge of the substances involved helps to interpret clinical features, anticipate the predicted clinical course, and inform appropriate monitoring and management decisions, including in some cases the administration of antidotes. Urine drug screening using immunoassays is sometimes performed, but has substantial limitations, including low sensitivity and specificity and, in particular, may not detect new psychoactive substances (NPS) [3], although methods have been developed to detect some specific compounds [4]. While liquid chromatography-mass spectrometry can be very sensitive for detecting substances of misuse, it is time consuming and expensive to perform. As a result, real-time analytical information is rarely available at the time of presentation, so the history provided by the patient or other witnesses is often the only source of information on substances involved. Research and surveillance studies of reported substance use, important for developing national drug control policies [5], may also rely on unvalidated user accounts for exposure information.
Evodiamine decreased the systemic exposure of pravastatin in non-alcoholic steatohepatitis rats due to the up-regulation of hepatic OATPs
Published in Pharmaceutical Biology, 2022
Ruifeng Liang, Wenjing Ge, Bingjie Li, Weifeng Cui, Xiaofan Ma, Yuying Pan, Gengsheng Li
The concentrations of pravastatin were determined using a Waters Acquity UPLC system coupled to Xevo TQS triple quadrupole mass spectrometer (Waters, Milford, USA). Following plasma, perfusate, bile, cell lysates, or tissue homogenate samples preparation, 500 μL of n-butanol saturated with water containing 50 μg/L diclofenac (internal standards) was mixed with 100 μL samples. After vortex mixing for 5 min and centrifuging at 12 000 g for 10 min, the organic layer was transferred and dried under a stream of nitrogen in an analytical evaporator (Thermo, Waltham, MA). The residue was dissolved in 100 μL of methanol and vortexed. Aliquots of the samples (5 μL) were injected into the liquid chromatography-mass spectrometry (LC-MS) system. Chromatographic separation was achieved on a Waters BEH C18 column (2.1 mm × 100 mm, 1.7 μm) with a mobile phase consisting of acetonitrile and water containing 0.1% formic acid (40:60, v/v) at a flow rate of 0.2 mL/min. The MS parameters were set as follows: ion spray voltage, −4500 V; source temperature, 500 °C; curtain gas, 20 L/h; and collision gas, 12 L/h. The mass spectrometric analysis was carried out on electrospray ionisation (ESI) source in negative ion mode, and the quantification was performed using multiple reaction monitoring (MRM) mode with m/z 423.4–320.9 for pravastatin and m/z 296.0–250.2 for diclofenac.