TY - JOUR. T1 - Quantification of sunitinib in human plasma by high-performance liquid chromatography-tandem mass spectrometry. AU - Minkin, Patton. AU - Zhao, Ming. AU - Chen, Zhaoyuan. AU - Ouwerkerk, Jan. AU - Gelderblom, Hans. AU - Baker, Sharyn D.. PY - 2008/10/15. Y1 - 2008/10/15. N2 - A rapid, sensitive and specific method was developed and validated using LC/MS/MS for determination of sunitinib in human plasma. Sample preparation involved a liquid-liquid extraction by the addition of 0.2 mL of plasma with 4.0 mL tert-butyl-methyl-ether extraction solution containing 25 ng/mL of the internal standard clozapine. Separation of compounds was achieved on a C18 (50 mm × 2.1 mm i.d., 3.5 μm) analytical column using a mobile phase consisting of acetonitrile/H20 (65:35, v/v) containing 0.1% formic acid and isocratic flow at 0.150 mL/min for 3 min. The analytes were monitored by tandem-mass spectrometry with electrospray positive ionization. Linear calibration curves in human plasma were ...
TY - JOUR. T1 - Determination of methylmalonyl coenzyme A by ultra high-performance liquid chromatography tandem mass spectrometry for measuring propionyl coenzyme A carboxylase activity in patients with propionic acidemia. AU - Gotoh, Kana. AU - Nakajima, Yoko. AU - Tajima, Go. AU - Watanabe, Yoriko. AU - Hotta, Yuji. AU - Kataoka, Tomoya. AU - Kawade, Yoshihiro. AU - Sugiyama, Naruji. AU - Ito, Tetsuya. AU - Kimura, Kazunori. AU - Maeda, Yasuhiro. PY - 2017/3/1. Y1 - 2017/3/1. N2 - Propionic acidemia (PA) is an inherited metabolic disease caused by low activity of propionyl coenzyme A (CoA) carboxylase (PCC), which metabolizes propionyl-CoA into methylmalonyl-CoA. Although many patients with PA have been identified by tandem mass spectrometry since the test was first included in neonatal mass screening in the 1990s, the disease severity varies. Thus, determining the specific level of PCC activity is considered to be helpful to grasp the severity of PA. We developed a new PCC assay method by ...
A quantitative, selective and fast ultra-high performance liquid chromatography tandem mass spectrometry method for the simultaneous analysis of 33 basic drugs in hair (amphetamines, cocaine, opiates, opioids and metabolites)
Florentina Laura Chiriac, Iuliana Paun, Florinela Pirvu, Luoana Florentina Pascu, Marcela Niculescu, Toma Galaon - Liquid Chromatography Tandem Mass Spectrometry Method for Ultra-Trace Analysis of Organic UV Filters in Environmental Water Samples
TY - JOUR. T1 - Online solid phase extraction with liquid chromatography-tandem mass spectrometry for determination of estrogens and glucocorticoids in water. AU - Goh, Shalene Xue Lin. AU - Duarah, Ankur. AU - Zhang, Lifeng. AU - Snyder, Shane A.. AU - Lee, Hian Kee. N1 - Funding Information: This work was supported by the Singapore National Research Foundation under its Environmental & Water Technologies Strategic Research Programme administered by the Environmental & Water Industry Programme Office (EWI) of the Public Utilities Board, Singapore (Grant no. 706-000-016-490/706-000-016-133 ). S.X.L. Goh is grateful for the award of a graduate research scholarship from the EWI. Publisher Copyright: © 2016 Elsevier B.V.. PY - 2016/9/23. Y1 - 2016/9/23. N2 - The present work describes the development of a novel fully automated online solid phase extraction (SPE) coupled with high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) using negative electrospray ionisation (ESI) for ...
TY - JOUR. T1 - Comparison of gas chromatography-mass spectrometry and liquid chromatography-tandem mass spectrometry methods to quantify α-tocopherol and αtocopherolquinone levels in human plasma. AU - Mottier, Pascal. AU - Gremaud, Eric. AU - Guy, Philippe A.. AU - Turesky, Robert J.. PY - 2002/2/1. Y1 - 2002/2/1. N2 - Two mass spectrometric methods were established for the quantitative analyses of α-tocopherol (TH) and its oxidation product α-tocopherolquinone (TQ) in human plasma. Both methods make use of isotopically labeled internal standards of different levels of deuteration (d3-TH and d6-TQ). Plasma (100 μl) was saponified in the presence of a mixture of antioxidants, and then TH and TQ were extracted with hexane. With the GC-MS method, the analytes were first converted into O-trimethylsilyl derivatives before analysis in the selective ion monitoring mode. The derivatization procedure led to the quantitative conversion of TQ into the O-trimethylsilyl derivative of ...
A novel liquid chromatography-tandem mass spectrometry method is described for the quantitative determination of the endogenous CYP 3A4/5 marker 4β-hydroxycholesterol in human K(2)-EDTA plasma. It is based on alkaline hydrolysis to convert esterified to free 4β-hydroxycholesterol, followed by analyt …
A stereoselective, sensitive and rapid liquid chromatography-tandem mass spectrometry (LC-MSMS) method for the determination of R-acenocoumarol and S-acenocoumarol in human plasma was developed and validated at IPRC bioanalytical labs. The procedure involved solid phase extraction of both enantiomers and their corresponding internal standard. The chromatographic separation was accomplished employing a chiral column and proper mobile phase. Detection was carried out using Waters Micromass® Quattro Premier mass spectrometer in multiple reaction monitoring (MRM) mode using turbo ion spray with negative ionization. The method was validated over a linear range of 0.40 - 40.00 ng/ml for R-acenocoumarol and 0.20 - 20.00 ng/ml for the S-acenocoumarol. Method validation covered different parameters such as linearity, accuracy, precision and stability. The method was successfully applied for the determination of R and S-acenocoumarol in plasma samples of 28 healthy subjects who participated in a pharmacokinetics
Abstract: A liquid chromatography tandem mass spectrometry method was developed for quantifying ten cannabinoids in oral fluid (OF). This method utilizes OF collected by the Quantisal device and concurrently quantifies cannabinol (CBN), cannabidiol (CBD), Δ9-tetrahydrocannabinol (THC), 11-hydroxy-Δ9-THC (11-OH-THC), 11-nor-9-carboxy-Δ9-THC (THC-COOH), 11-nor-9-carboxy-Δ9-THC glucuronide (THC-COOH-gluc), Δ9-THC glucuronide (THC-gluc), cannabigerol (CBG), tetrahydrocannabiverin (THCV), and Δ9-tetrahydrocannabinolic acid A (THCA-A). Solid phase extraction was optimized using Oasis Prime HLB 30 mg 96-well plates. Cannabinoids were separated by liquid chromatography over a BEH C18 column and detected by a Waters TQ-S micro tandem mass spectrometer. The lower limits of quantification (LLOQ) were 0.4 ng/mL for CBN, CBD, THC, 11-OH-THC, THC-gluc, and THCV; and 1.0 ng/mL for THC-COOH, THC-COOH-gluc, CBG and THCA-A. Linear ranges extended to 2000 ng/mL for THC and 200 ng/mL for all other analytes. ...
RATIONALE Neonicotinoids (NNIs) are the fastest expanding group of pesticides in the world over the last two decades; however, they may be a significant contributing factor to bee mortality. The widespread use of NNIs makes it critical to monitor their residuals in the environment. Published methods for NNI analysis are mainly focused on agricultural and food products, and many of them only measured a portion of the commercially available NNIs. METHODS Utilizing a biphenyl stationary-phase column, a sensitive liquid chromatography/tandem mass spectrometry (LC/MS/MS) method was developed to determine eight NNIs, including acetamiprid, clothianidin, dinotefuran, flonicamid, imidacloprid, nitempyram, thiacloprid and thiamethoxam in environmental water. Two multiple reaction monitoring (MRM) transitions were monitored for each compound to ascertain true positive identification. Isotope-labelled NNIs, d3-acetamiprid, d3-clothianidin, d4-imidacloprid and d3-thiamethoxam, were used to compensate for
An improved method for determining levels of levosulpiride in human plasma using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed and validated. The protein precipitation method was used for plasma sample preparation. Levosulpiride and an internal standard (IS) were isocratically separated on a UPLC BEN C(18) column with a mobile phase of ammonium formate buffer (1 mM, adjusted to pH 3 with formic acid) and acetonitrile (60:40, v/v). MS/MS detection was performed by monitoring the parent -, daughter pair of levosulpiride and the IS at m/z 342 -, 112 and 329 -, 256, respectively. The method was linear from 2.5 to 200 ng/mL and exhibited acceptable precision and percent recovery. The method was successfully demonstrated in pharmacokinetic and bioequivalence studies of two levosulpiride oral formulations administered to healthy volunteers. When compared to the previous LC-MS methods, the proposed method is faster, well-validated, and uses lesser plasma ...
TY - JOUR. T1 - Validation of a high throughput method for serum/plasma testosterone using liquid chromatography tandem mass spectrometry (LC-MS/MS). AU - Singh, Ravinder Jit. PY - 2008/12/12. Y1 - 2008/12/12. N2 - Testosterone, the major androgenic hormone in humans, is commonly measured to aid in the diagnosis of clinical conditions related to its excess or deficiency. In addition, testosterone measurements are used to monitor testosterone replacement-, or antiandrogen therapy. Most commonly, automated direct immunoassays have been used to measure testosterone in human serum. Their advantage compared with other methodologies, lies in high- and rapid sample throughput with minimal human intervention. However, many automated testosterone immunoassays suffer from poor accuracy at the low concentration levels (,50 ng/dL) seen in women and children, or in men undergoing anti-androgen therapy. Our objective was to develop a LC-MS/MS method which measures testosterone in human serum while fulfilling ...
The obligate intracellular lifestyle of Plasmodium falciparum and the difficulties in obtaining sufficient amounts of biological material have hampered the study of specific metabolic pathways in the malaria parasite. Thus, for example, the pools of sugar nucleotides required to fuel glycosylation reactions have never been studied in-depth in well-synchronized asexual parasites or in other stages of its life cycle. These metabolites are of critical importance, especially considering the renewed interest in the presence of N-, O-, and other glycans in key parasite proteins. In this work, we adapted a liquid chromatography tandem mass spectrometry (LC-MS/MS) method based on the use of porous graphitic carbon (PGC) columns and MS-friendly solvents to quantify sugar nucleotides in the malaria parasite. We report the thorough quantification of the pools of these metabolites throughout the intraerythrocytic cycle of P. falciparum The sensitivity of the method enabled, for the first time, the targeted ...
TY - JOUR. T1 - Analysis of metribuzin and its metabolites in livestock products and seafoods by liquid chromatography-tandem mass spectrometry. AU - Kai, Shigemi. AU - Akaboshi, Takeshi. AU - Waki, Masumi. AU - Fuzimaki, Teruhisa. AU - Kanazawa, Hideko. PY - 2011/2. Y1 - 2011/2. N2 - A method for simultaneous determination of metribuzin (MET) and three metribuzin metabolites in livestock products and seafoods by liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed. MET and its metabolites were extracted from a sample with acetonitrile, followed by InertSepC18 and BondElut SAX cartridge cleanup. The LC separation was performed on a C18 column using 0.01 mol/L ammonium formate-acetonitrile-methanol (70 : 21 : 9) as the mobile phase and MS detection with both positive and negative ion electrospray ionization. The mean recoveries from 10 livestock products and seafoods were generally ,60%, and the relative standard deviations were ,20%.. AB - A method for simultaneous ...
Liquid chromatography tandem mass spectrometry is one of the most specific techniques available in clinical laboratories. In the past, immunoassays were the primary methodology for analysis of steroids in biological samples because they are rapid and easy to perform. However, these methods were shown to suffer from the lack of specificity for measuring many of the diagnostically important steroids. LC-MS/MS overcomes many of the limitations of immunoassays, enhances diagnostic utility of the testing, and expands diagnostic capabilities in endocrinology. In addition to the superior quality of the measurements, LC-MS/MS allows high throughput testing using small sample volume with minimal sample preparation, and frees the laboratory from dependence on suppliers of assay specific reagents. LC-MS/MS is being widely employed for routine measurement of steroids, and the methodology plays an important role in the standardization and harmonization of measurements among clinical laboratories.. ...
Peptide identification is an important problem in proteomics. One of the most popular scoring schemes for peptide identification is X-Corr (cross-correlation). Since calculating X-Corr is computationally intensive, a lot of efforts have been made to develop fast X-Corr engines. However, the existing X-Corr engines are not suitable for high-resolution MS/MS spectrometry because they are either slow or require a specific type of CPU. We present a portable high-speed X-Corr engine for high-resolution tandem mass spectrometry by developing a novel algorithm for calculating X-Corr. The algorithm enables X-Corr calculation 1.25-49 times faster than previous algorithms for 0.01 Da fragment tolerance. Furthermore, our engine is easily portable to any machine with different types of CPU because it is developed in C language. Hence, our X-Corr engine will expedite peptide identification by high-resolution tandem mass spectrometry ...
A highly sensitive and selective liquid chromatography-mass spectrometry (LC-MS) method has been developed for the determination of epirubicin in serum and c...
Busulfan is an alkylating agent widely used in the ablation of bone marrow cells before hematopoietic stem cell transplant. Due to large intraindividual and interindividual variations, and narrow therapeutic window, therapeutic drug monitoring of busulfan is warranted. A quick and reliable HPLC-MS/MS method was developed for the assay of plasma busulfan. HPLC involved C18 column, and MS/MS was used in electrospray ionization (ESI) positive mode. Quantitation and identification of busulfan was made using various multiple reactions monitoring (MRMs). Isotopic labeled busulfan-d8 was used as the internal standard. The method is linear from 50 to 2500 ng/mL and has with-in run and between-run imprecision of |10|%.
TY - JOUR. T1 - Reference ranges for testosterone in men generated using liquid chromatography tandem mass spectrometry in a community-based sample of healthy nonobese young men in the framingham heart study and applied to three geographically distinct cohorts. AU - Bhasin, Shalender. AU - Pencina, Michael. AU - Jasuja, Guneet Kaur. AU - Travison, Thomas G.. AU - Coviello, Andrea. AU - Orwoll, Eric. AU - Wang, Patty Y.. AU - Nielson, Carrie. AU - Wu, Frederick. AU - Tajar, Abdelouahid. AU - Labrie, Fernand. AU - Vesper, Hubert. AU - Zhang, Anqi. AU - Ulloor, Jagadish. AU - Singh, Ravinder. AU - DAgostino, Ralph. AU - Vasan, Ramachandran S.. PY - 2011/8/1. Y1 - 2011/8/1. N2 - Context: Reference ranges are essential for partitioning testosterone levels into low or normal and making the diagnosis of androgen deficiency. We established reference ranges for total testosterone (TT) and free testosterone (FT) in a community-based sample of men. Methods: TT was measured using liquid chromatography ...
BACKGROUND: Oral fluid is an alternative matrix with potential applications in road-side drug screening, work-place testing, drug treatment programs, and epidemiological surveys. Development of methods for extensive drug screening in oral fluid is warranted. METHODS: We developed a liquid chromatography- tandem mass spectrometry (LC-MS/MS) method for drug screening of preserved oral fluid collected with the Intercept collection device. Samples were prepared by liquid-liquid extraction with ethylacetate/heptane (4:1). LC-separation was achieved with an Atlantis dC18-column (2.1 x 50 mm, 3 microm particle). Mass detection was performed by positive ion mode electrospray LC-MS/MS and included the following drugs/metabolites: morphine, 6-monoacetylmorphine, codeine, buprenorphine, methadone, amphetamine, methamphetamine, 3,4-methylenedioxymethamphetamine, 3,4-methylenedioxyamphetamine, 3,4-methylenedioxyethylamphetamine, cocaine, benzoylecgonine, Delta-9-tetrahydrocannabinol, lysergic acid ...
TY - JOUR. T1 - Asymmetric dimethylarginine predicts survival in the elderly. AU - Pizzarelli, Francesco. AU - Maas, Renke. AU - Dattolo, Pietro. AU - Tripepi, Giovanni. AU - Michelassi, Stefano. AU - DArrigo, Graziella. AU - Mieth, Maren. AU - Bandinelli, Stefania. AU - Ferrucci, Luigi. AU - Zoccali, Carmine. PY - 2013/12. Y1 - 2013/12. N2 - Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of nitric oxide synthase implicated in several age-related biological mechanisms such as telomere shortening and cell senescence. We tested the hypothesis that ADMA blood level is an independent predictor of mortality in elderly. This is a longitudinal population-based cohort study. Participants are a representative cohort of 1,025 men and women (age range 65-102 years) living in Chianti area, Tuscany, Italy. The plasma ADMA was measured by liquid chromatography- tandem mass spectrometry. During the follow-up (95±32 months), 384 individuals died, of whom 141 (37 %) died of cardiovascular (CV) ...
SICHILONGO, Kwenga F.; MUCKOYA, Vallerie A. y NINDI, Mathew M.. A rapid and sensitive LC-MS/MS method for the determination of multi-class residues of antibiotics in chicken liver. S.Afr.j.chem. (Online) [online]. 2015, vol.68, pp.01-06. ISSN 1996-840X. http://dx.doi.org/10.17159/0379-4350/2015/v68a1.. A very sensitive, simple and cost-effective liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) method for the determination of multi-class antibiotics in chicken liver was developed. The drugs under consideration were sulfaguanidine and sulfamethazole, trimethoprim, tetracycline, chlortetracycline and tylosin. Linear calibrations were established for all the analytes and the R2 values ranged between 0.9990 and 0.9997. The limits of quantitation (LOQs) varied between 0.025 and 78.8 μg kg-1. The limit of detections (LODs) were better than those that have been reported for the same antibiotics in many instances in other studies and ranged between 0.010-31.5 μg kg-1 with the ...
SICHILONGO, Kwenga F.; MUCKOYA, Vallerie A. e NINDI, Mathew M.. A rapid and sensitive LC-MS/MS method for the determination of multi-class residues of antibiotics in chicken liver. S.Afr.j.chem. (Online) [online]. 2015, vol.68, pp.01-06. ISSN 1996-840X. http://dx.doi.org/10.17159/0379-4350/2015/v68a1.. A very sensitive, simple and cost-effective liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) method for the determination of multi-class antibiotics in chicken liver was developed. The drugs under consideration were sulfaguanidine and sulfamethazole, trimethoprim, tetracycline, chlortetracycline and tylosin. Linear calibrations were established for all the analytes and the R2 values ranged between 0.9990 and 0.9997. The limits of quantitation (LOQs) varied between 0.025 and 78.8 μg kg-1. The limit of detections (LODs) were better than those that have been reported for the same antibiotics in many instances in other studies and ranged between 0.010-31.5 μg kg-1 with the ...
An original liquid chromatography-tandem mass spectrometry (LC-MS-MS) method coupled to online extraction has been developed for cyanide determination in blood. A method involving fluorimetric detection after naphthalene-2,3-dicarboxyaldehyde (NDA) complexation by taurine in the presence of cyanide was previously described. Its performance was limited because of the absence of an internal standard (IS). Using cyanide isotope 13C15N as IS allowed quantification in MS-MS. After the addition of 13C15N, 25 µL of blood were diluted in water and deproteinized with methanol. Following derivatization with NDA and taurine for 10 min at 4°C, 100 µL was injected into the online LC-MS-MS system. An Oasis HLB was used as an extraction column, and a C18 Atlantis was the analytical column. The chromatographic cycle was performed with an ammonium formate (20 mM, pH 2.8) (solvent A) and acetonitrile/solvent A (90:10, v/v) gradient in 6 min. Detection was performed in negative electrospray ionization mode ...
Disease-specific compounds (biomarkers) are analyzed in clinical laboratories to assist with diagnosing diseases. This thesis describes development and validation of liquid chromatography tandem mass spectrometry (LC-MS/MS) based tests for diagnosing a diverse group of endocrine and metabolic diseases. The analytical methods used on-line and off-line sample extraction and analytical derivatization as means of enhancing the analytical sensitivity, specificity and clinical utility. All developed methods were extensively validated and reference intervals for the biomarker concentrations were established in blood samples of healthy adults and children. Advantages of the LC-MS/MS as an analytical technique include possibility of simultaneous measurement of multiple analytes and ability of confirming their identity. In this thesis we proposed and evaluated approaches for the assessment of the specificity of analysis in the methods that use tandem mass spectrometry detection. To enhance throughput of ...
La presente simulazione è stata realizzata sulla base delle specifiche raccolte sul tavolo ER del Focus Group IRIS coordinato dallUniversità di Modena e Reggio Emilia e delle regole riportate nel DM 598/2018 e allegata Tabella A. Cineca, lUniversità di Modena e Reggio Emilia e il Focus Group IRIS non si assumono alcuna responsabilità in merito alluso che il diretto interessato o terzi faranno della simulazione. Si specifica inoltre che la simulazione contiene calcoli effettuati con dati e algoritmi di pubblico dominio e deve quindi essere considerata come un mero ausilio al calcolo svolgibile manualmente o con strumenti equivalenti ...
High throughput online solid phase extraction-ultra high performance liquid chromatography-tandem mass spectrometry method for polyfluoroalkyl phosphate esters, perfluoroalkyl phosphonates, and other perfluoroalkyl substances in human serum, plasma, and whole ...
In forensic investigations, such as drug-facilitated crimes, reference values are useful for interpretation of hair results. The aim of this study was to establish levels of zopiclone and two main metabolites, N-desmethylzopiclone and zopiclone N-oxide, in hair after the administration of a single dose of zopiclone, as very limited data are published. A controlled study was performed, where 16 volunteers consumed either 5 or 10mg zopiclone. Hair was sampled prior to consumption and 14, 30, 60, and 120 days after intake. The deposition of drug in hair segments of all sampling time points was followed in small hair segments of 5-mm, using a validated ultra-high performance liquid chromatography-tandem mass spectrometry method. In all participants, hair segments corresponding to the time of intake were positive for zopiclone, but also with lower concentrations in the neighbouring segments. The highest zopiclone concentrations were detected in samples collected 30 or 60 days after intake. For all ...
TY - JOUR. T1 - Effect of ionization modifiers on the simultaneous analysis of all classes of phospholipids by nanoflow liquid chromatography/tandem mass spectrometry in negative ion mode. AU - Bang, Dae Young. AU - Lim, Sangsoo. AU - Moon, Myeong Hee. N1 - Funding Information: This study was supported by the National Research Foundation (NRF) of Korea grant (No. 2011-0016438 ) funded by the Korean government (MEST) and in part by a grant (No. 2011-0001125 ). PY - 2012/6/1. Y1 - 2012/6/1. N2 - The effect of ionization modifiers added to the mobile phase of nanoflow liquid chromatography-tandem mass spectrometry (nLC-ESI-MS 3) on the simultaneous analysis of all phospholipid (PL) classes in negative ion mode has been investigated. While MS analysis of most PL classes is carried out in negative ion mode, analysis of neutral polar (polar but electrically neutral) lipids like phosphatidylcholine (PC) and sphingomyelin (SM) is highly efficient in positive ion mode. Therefore, analysis of PL mixture ...
Charlène Pouech, Florent Lafay, Laure Wiest, Robert Baudot, Didier Léonard, et al.. Monitoring the extraction of additives and additive degradation products from polymer packaging into solutions by multi-residue method including solid phase extraction and ultra-high performance liquid chromatography-tandem mass spectrometry analysis. Analytical and Bioanalytical Chemistry, Springer Verlag, 2014, 406 (5), pp.1493-1507. 〈10.1007/s00216-013-7551-4〉. 〈hal-00924245〉 ...
TY - JOUR. T1 - Performance metrics for liquid chromatography-tandem mass spectrometry systems in proteomics analyses. AU - Rudnick, Paul A.. AU - Clauser, Karl R.. AU - Kilpatrick, Lisa E.. AU - Tchekhovskoi, Dmitrii V.. AU - Neta, Pedatsur. AU - Blonder, Nikša. AU - Billheimer, Dean D.. AU - Blackman, Ronald K.. AU - Bunk, David M.. AU - Cardasis, Helene L.. AU - Ham, Amy Joan L.. AU - Jaffe, Jacob D.. AU - Kinsinger, Christopher R.. AU - Mesri, Mehdi. AU - Neubert, Thomas A.. AU - Schilling, Birgit. AU - Tabb, David L.. AU - Tegeler, Tony J.. AU - Vega-Montoto, Lorenzo. AU - Variyath, Asokan Mulayath. AU - Wang, Mu. AU - Wang, Pei. AU - Whiteaker, Jeffrey R.. AU - Zimmerman, Lisa J.. AU - Carr, Steven A.. AU - Fisher, Susan J.. AU - Gibson, Bradford W.. AU - Paulovich, Amanda G.. AU - Regnier, Fred E.. AU - Rodriguez, Henry. AU - Spiegelman, Cliff. AU - Tempst, Paul. AU - Liebler, Daniel C.. AU - Stein, Stephen E.. PY - 2010/2. Y1 - 2010/2. N2 - A major unmet need in LC-MS/MS-based ...
Sigma-Aldrich offers abstracts and full-text articles by [Gabriela Peste, Nela Bibire, Mihai Apostu, Aurel Vlase, Corneliu Oniscu].
Adequate vitamin D status is necessary throughout life in terms of maintaining bone strength, calcium and phosphorus balance, as well as prevention of rickets in children and osteomalacia in adults. The accepted biomarker used for the assessment of vitamin D status is circulating total 25-hydroxyvitamin D (25(OH)D) concentration, which is comprised of the sum of 25-hydroxyvitamin D3 (25(OH)D3) and 25-hydroxvitamin D2 (25(OH)D2) The use of liquid chromatography-tandem mass spectrometry (LC-MS/MS) for the analysis of total 25(OH)D has also enabled the detection of low concentration, minor vitamin D metabolites in serum. The aims of this work were to examine the impact of three such minor vitamin D metabolites, 25(OH)D2, 24,25-dihydroxyvitamin D (24,25(OH)2D), and 3 epimer of 25(OH)D3 (3-epi-25(OH)D3) on the assessment of vitamin D nutritional status and also to provide further insight and refinement of our understanding of the vitamin D metabolic pathway. This required the development and ...
Steuer, Andrea E; Poetzsch, Michael; Stock, Lorena; Eisenbeiss, Lisa; Schmid, Yasmin; Liechti, Matthias E; Kraemer, Thomas (2017). Development and validation of an ultra-fast and sensitive microflow liquid chromatography-tandem mass spectrometry (MFLC-MS/MS) method for quantification of LSD and its metabolites in plasma and application to a controlled LSD administration study in huma. Drug Testing and Analysis, 9(5):788-797. ...
University of Leicester researchers writing in the journal Chemical Research in Toxicology say they have found convincing evidence that cannabis smoke damages DNA and it could potentially increase the risk of cancer development in humans.Using a newly developed highly sensitive liquid chromatography-tandem mass spectrometry method, the University
Liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) has become one of the most used tools in mass spectrometry based proteomics. Various algorithms have since been developed to automate the process for modern high-throughput LC-MS/MS experiments. A probability based statistical scoring model for assessing peptide and protein matches in tandem MS database search was derived. The statistical scores in the model represent the probability that a peptide match is a random occurrence based on the number or the total abundance of matched product ions in the experimental spectrum. The model also calculates probability based scores to assess protein matches. Thus the protein scores in the model reflect the significance of protein matches and can be used to differentiate true from random protein matches. The model is sensitive to high mass accuracy and implicitly takes mass accuracy into account during scoring. High mass accuracy will not only reduce false positives, but also improves the
Lipids are ubiquitous and serve numerous biological functions; thus lipids have been shown to have great potential as candidates for elucidating biomarkers and pathway perturbations associated with disease. Methods expanding coverage of the lipidome increase the likelihood of biomarker discovery and could lead to more comprehensive understanding of disease etiology. We introduce LipidMatch, an R-based tool for lipid identification for liquid chromatography tandem mass spectrometry workflows. LipidMatch currently has over 250,000 lipid species spanning 56 lipid types contained in in silico fragmentation libraries. Unique fragmentation libraries, compared to other open source software, include oxidized lipids, bile acids, sphingosines, and previously uncharacterized adducts, including ammoniated cardiolipins. LipidMatch uses rule-based identification. For each lipid type, the user can select which fragments must be observed for identification. Rule-based identification allows for correct annotation of
Grape pomace extract (GPE) is a rich and relatively low-cost source of phenolic compounds. However, little is known about the main GPE metabolites in mammals, which could help explain the observed health-promoting effects. This study investigated the presence of parent compounds from flavanol, flavonol and stilbene families and their metabolites in rat plasma and tissues after an acute intake of GPE in doses of 300 and 600 mg kg/body weight. The measurement of free compounds and their metabolites was performed by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Results showed the presence of epicatechin, epicatechin methyl-glucuronide, epicatechin methyl-sulphate, catechin, catechin-glucuronide, quercetin methyl-glucuronide, resveratrol-3-glucuronide, resveratrol-4-glucuronide and resveratrol-3-sulphate in plasma, which was dose dependent. The most abundant measured compound in plasma was epicatechin-glucuronide. The presence of glucuronidated and ...
Liquid Chromatography / Tandem Mass Spectrometry (LS/MS/MS). Liquid chromatography/tandem mass spectrometry provides identification of analytes of interest within a mixture based on retention time and characteristic parent/daughter ion fragmentation patterns, which provides the compounds unique molecular fingerprint. When liquid chromatography is suitable for separation of compounds, LC/MS/MS can provide significantly greater sensitivity than the corresponding gas chromatography/mass spectrometry (i.e., GC/MS). KorvaLabs employs LC/MS/MS for the identification of substances in white powders - such as in the case of certification of dietary supplements - and for certain compounds in urine where GC/MS is not sufficient.. Gas Chromatography / Mass Spectrometry (GC/MS). Like LC/MS, the related gas chromatography/mass spectrometry (i.e., GC/MS)provides identification based on retention time and ion fragmentation patterns; however, GC/MS… KorvaLabs uses GC/MS for the detection of most banned ...
In early 2011, a food sample of pink colored sugar coated sesame seed from Pakistan was sent to the lab for color determination. The paper chromatography method could not determine any dyes. (As found out later, the unknown pink dye was not an acid dye.) From research it was found that Rhodamine B was a pink water soluble basic dye commonly used as a food adulterant. A standard was ordered and then a qualitative high performance Liquid chromatography-tandem mass spectrometry (HPLC/MS/MS) method was developed (Waters UPLC Aquity w/Waters Premier XE triple quadrapole) to determine Rhodamine B. After utilizing this new method, Rhodamine B was found in the sugar coated sesame seed.. Rhodamine B is an industrial dye and is not allowed in food anywhere in the world. Industrial dyes are not allowed in food because they are toxic; in fact, some industrial dyes are used for suicide.2,3,4 In addition, industrial dyes are not made to food grade specifications with regard to dye purity, heavy metal (i.e., ...
Abstract To support therapeutic drug monitoring of patients with cancer, a fast and accurate method for simultaneous quantification of the registered anticancer drugs afatinib, axitinib, ceritinib, crizotinib, dabrafenib, enzalutamide, regorafenib and trametinib in human plasma using liquid chromatography tandem mass spectrometry was developed and...
Environmental phenols are a group of chemicals with widespread uses in consumer and personal care products, food and beverage processing, and in pesticides. We assessed exposure to benzophenone-3, bisphenol A (BPA), triclosan, methyl- and propyl parabens, and 2,4- and 2,5-dichlorophenol or their precursors in 506 pregnant women enrolled in the National Childrens Study (NCS) Vanguard Study. We measured the urinary concentrations of the target phenols by using online solid-phase extraction-isotope dilution high performance liquid chromatography-tandem mass spectrometry. NCS women results were compared to those of 524 similar-aged women in the National Health and Nutrition Examination Survey (NHANES) 2009-2010, and to 174 pregnant women in NHANES 2005-2010. In the NCS women, we found significant racial/ethnic differences ( ...
Protein glycosylation has a major influence on functions of proteins. Studies have shown that aberrations in glycosylation are indicative of disease conditions. This has prompted major research activities for comparative studies of glycoproteins in biological samples. Multiple reaction monitoring (M …
Labeled as emerging organic contaminants, pharmaceuticals and personal care products (PPCPs) have been the focus of global environmental research for over a decade. PPCPs have caused widespread concern due to their extensive use. As PPCPs were designed to correct, enhance, or protect a specific physiological or endocrine condition, their target effects in humans and/or farm stocks are relatively well understood and documented. However, there is limited knowledge about their unintended effects in the environment. To address the occurrence, distribution and fate of PPCPs in the environment, efficient and reliable analytical methods are needed. The relatively low concentration, high polarity, and thermal lability of some PPCPs, together with their interaction with complex environmental matrices, makes their analysis challenging. Sample preparation followed by GC or HPLC separation and mass spectrometry (MS) detection has become the standard approach for evaluating PPCPs in environmental samples. ...
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Detailed HPLC/MS/MS studies on blood samples collected from normal healthy human subjects were performed to generate a reference of sphingolipid (SPL) levels for future investigations into diseases utilizing blood as a matrix. The impact of sample collection (serum, plasma, and anticoagulants), attributes of blood donors (gender, fasting state) and handling of blood were investigated. In addition, the SPL metabolomic profiles (18C sphingoid backbone, C14 to C26 N-acyl chain) of human plasma were determined. Blood was collected from healthy males and non-pregnant females under fasting and nonfasting conditions with and without various anticoagulants (EDT A, citrate and heparin). Plasma prepared with EDT A was determined to be ideal over the other blood formulations for SPL analyses, yielding the lowest variances in determination of most analyzed SPL classes. Sph1 P levels were higher in serum than plasma (0.67~M vs. 0.32jJM) with no effect on other SPLs in EDTA plasma. There were no variances on ...
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Journal of Chemistry is a peer-reviewed, Open Access journal that publishes original research articles as well as review articles on all aspects of fundamental and applied chemistry.