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1. Calibration strategies for laser ablation ICP-MS in biological studies: A review

Author:
Huijie Pan; Liuxing Feng; Yanli Lu; Yachen Han; Jinping Xiong; Hongmei Li
Source:
Trends in analytical chemistry 2022 v.156 pp. 116710
ISSN:
0165-9936
Subject:
isotope dilution technique,   etc   ; analytical chemistry; atomic absorption spectrometry; calibration; fractionation; quantitative analysis;     Show all 6 Subjects
Abstract:
... Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) has attracted attentions for its high sensitivity and sufficient spatial resolution in the in-situ analysis and imaging in biological studies. However, due to the matrix effect and elemental fractionation, achieving quantitative analysis of elements or proteins in biological samples are still challenging. Calibration is a nece ...
DOI:
10.1016/j.trac.2022.116710

2. Production and stability of Oxygen-18 labeled Caribbean ciguatoxins and gambierones

Author:
Elizabeth M. Mudge; Juris Meija; Silvio Uhlig; Alison Robertson; Pearse McCarron; Christopher O. Miles
Source:
Toxicon 2022 v.211 pp. 11-20
ISSN:
0041-0101
Subject:
isotope dilution technique,   etc   ; Gambierdiscus; ciguatera; ciguatoxin; metabolism; pH; sodium borohydride; solvents; Caribbean;     Show all 9 Subjects
Abstract:
... Ciguatoxins (CTXs) and gambierones are ladder-shaped polyethers associated with ciguatera poisoning and Gambierdiscus spp. Several of these compounds contain carbonyl or hemiketal groups, which have the potential to exchange with ¹⁸O-labeled water under acidic conditions. The effects of solvent composition and acid on the rate of exchange and on the stability of the labels at various pH values wer ...
DOI:
10.1016/j.toxicon.2022.03.005

3. Evidence that methoxypyrazine accumulation is elevated in Shiraz rachis grown on Ramsey rootstock, increasing ‘green’ flavour in wine

Author:
D.L. Capone; I.L. Francis; P.R. Clingeleffer; S.M. Maffei; P.K. Boss
Source:
Australian journal of grape and wine research 2022 v.28 no.2 pp. 304-315
ISSN:
1322-7130
Subject:
isotope dilution technique,   etc   ; cultivars; flavor; grapes; odors; research; rootstocks; stable isotopes; vigor; wines;     Show all 10 Subjects
Abstract:
... BACKGROUND AND AIMS: ‘Green’ sensory characters in Shiraz wines were observed in wines produced from different rootstocks. The compounds responsible were investigated as these attributes are generally seen as negative. METHODS AND RESULTS: GC/MS‐olfactometry and stable isotope dilution analysis methods were used to identify and quantify a range of volatile compounds associated with ‘green’ sensory ...
DOI:
10.1111/ajgw.12551

4. A new method for the evaluation of measurement uncertainty in strict accordance with measurement model: Determination of total thyroxine in human serum by triple isotope dilution mass spectrometry

Author:
Man Liang; Huimin Wang; Chunlong Liu; Yabo Li; Shuqi An; Yanlin Han
Source:
Talanta 2022 v.246 pp. 123494
ISSN:
0039-9140
Subject:
isotope dilution technique,   etc   ; blood serum; humans; isotopes; liquid chromatography; mass spectrometry; models; thyroxine; uncertainty;     Show all 9 Subjects
Abstract:
... The rigorous and reasonable evaluation of uncertainty is crucial for the reliability of the results of a reference measurement procedure. A new uncertainty budget is proposed for uncertainty evaluation of a reference measurement procedure for total thyroxine in human serum based on isotope dilution liquid chromatography-mass spectrometry. In this work, a measurement model for uncertainty evaluatio ...
DOI:
10.1016/j.talanta.2022.123494

5. Total Asymmetric Synthesis and Stereochemical Confirmation of (+)- and (−)-Lyoniresinol and Its Deuterated Analogues

Author:
Tuan Minh Luong; Lisa I. Pilkington; David Barker
Source:
Journal of organic chemistry 2022 v.87 no.6 pp. 4254-4262
ISSN:
1520-6904
Subject:
isotope dilution technique,   etc   ; bitterness; enantiomers; lignans; organic chemistry; stable isotopes; stereochemistry; stereoselective synthesis; taste;     Show all 9 Subjects
Abstract:
... Lyoniresinol and its derivatives are lignans which have been isolated from a plethora of plant species. In addition to exhibiting a range of interesting biological activities including anticancer, anti-inflammatory, antimicrobial, and others, these compounds have also been discovered in wines and spirits and shown to have gustatory effects in these alcoholic matrices. (+)-Lyoniresinol 1 is reporte ...
DOI:
10.1021/acs.joc.1c03085

6. Assessing the Lability and Environmental Mobility of Organically Bound Copper by Stable Isotope Dilution

Author:
Ezzat R. Marzouk; Erica Donner; Frank von der Kammer; Elizabeth H. Bailey; Waleed H. Shetaya; Scott D. Young; Enzo Lombi
Source:
Environmental science & technology 2022 v.56 no.9 pp. 5580-5589
ISSN:
1520-5851
Subject:
isotope dilution technique,   etc   ; environmental science; gel chromatography; organic matter; risk assessment; stable isotopes; technology; toxicity;     Show all 8 Subjects
Abstract:
... The environmental mobility of Cu and therefore its potential toxicity are closely linked to its attachment to natural organic matter (NOM). Geochemical models assume full lability of metals bound to NOM, especially under strong oxidizing conditions, which often leads to an overestimation of the lability of soil metals. Stable isotope dilution (SID) has been successfully applied to estimate the lab ...
DOI:
10.1021/acs.est.2c00964

7. Interlaboratory comparison of 25-hydroxyvitamin D assays: Vitamin D Standardization Program (VDSP) Intercomparison Study 2 — Part 1 liquid chromatography – tandem mass spectrometry (LC-MS/MS) assays — impact of 3-epi-25-hydroxyvitamin D3 on assay performance

Author:
Stephen A. Wise; Johanna E. Camara; Carolyn Q. Burdette; Grace Hahm; Federica Nalin; Adam J. Kuszak; Joyce Merkel; Ramón A. Durazo-Arvizu; Emma L. Williams; Andrew N. Hoofnagle; Fiona Ivison; Ralf Fischer; Jody M. W. van den Ouweland; Chung S. Ho; Emmett W. K. Law; Jean-Nicolas Simard; Renaud Gonthier; Brett Holmquist; Sarah Meadows; Lorna Cox; Kimberly Robyak; Michael H. Creer; Robert Fitzgerald; Michael W. Clarke; Norma Breen; Pierre Lukas; Étienne Cavalier; Christopher T. Sempos
Source:
Analytical and bioanalytical chemistry 2022 v.414 no.1 pp. 333-349
ISSN:
1618-2642
Subject:
isotope dilution technique,   etc   ; analytical chemistry; blood serum; liquid chromatography; metabolites; regression analysis; tandem mass spectrometry;     Show all 7 Subjects
Abstract:
... An interlaboratory comparison study was conducted by the Vitamin D Standardization Program (VDSP) to assess the performance of liquid chromatography – tandem mass spectrometry (LC-MS/MS) assays used for the determination of serum total 25-hydroxyvitamin D (25(OH)D), which is the sum of 25-hydroxyvitamin D₂ (25(OH)D₂) and 25-hydroxyvitamin D₃ (25(OH)D₃). A set of 50 single-donor samples was assigne ...
DOI:
10.1007/s00216-021-03576-1

8. Accurate determination of amino acids by quadruple isotope dilution-reverse phase liquid Chromatography-Tandem mass spectrometry after derivatization with 2-Naphthoyl chloride

Author:
Elif Öztürk Er; Sezin Erarpat; Süleyman Bodur; Ömer Tahir Günkara; Belma Özbek; Sezgin Bakırdere
Source:
Journal of chromatography 2022 v.1667 pp. 462870
ISSN:
0021-9673
Subject:
isotope dilution technique,   etc   ; blood serum; chlorides; derivatization; humans; reversed-phase liquid chromatography; tandem mass spectrometry; urine;     Show all 8 Subjects
Abstract:
... The determination of amino acids in biological samples is central to the diagnosis of inherited metabolic disorders and also gives significant information about the metabolisms in the cells and living body. The development of analytical method for reliable quantification of amino acids in biological samples is still challenging because of the polar nature of amino acids and complex nature of biolo ...
DOI:
10.1016/j.chroma.2022.462870

9. Quantitation of thrombin-activatable fibrinolysis inhibitor in human plasma by isotope dilution mass spectrometry

Author:
Jun X. Wheeler; Craig Thelwell; Peter Rigsby; Gail Whiting
Source:
Analytical biochemistry 2022 v.638 pp. 114413
ISSN:
0003-2697
Subject:
isotope dilution technique,   etc   ; acetonitrile; amino acids; digestion; fibrinolysis; humans; liquid chromatography; mass spectrometry; reference standards; traceability;     Show all 10 Subjects
Abstract:
... Measurement of Thrombin-activatable fibrinolysis inhibitor (TAFI) in human plasma is dependent on reproducible assays. To date, standards for measuring TAFI are frequently calibrated relative to pooled normal human plasma and arbitrarily assigned a potency of 100% TAFI, despite variation in TAFI concentrations between plasma pools. Alternatively, TAFI calibrators can be assigned a value in SI unit ...
DOI:
10.1016/j.ab.2021.114413

10. Quantitative metabolomics for dynamic metabolic engineering using stable isotope labeled internal standards mixture (SILIS)

Author:
Yuki Soma; Masatomo Takahashi; Yuri Fujiwara; Noriyuki Tomiyasu; Maiko Goto; Taizo Hanai; Yoshihiro Izumi; Takeshi Bamba
Source:
Journal of bioscience and bioengineering 2022 v.133 no.1 pp. 46-55
ISSN:
1389-1723
Subject:
isotope dilution technique,   etc   ; Escherichia coli; butyrates; cell proliferation; fermentation; isotope labeling; mass spectrometry; metabolomics; stable isotopes;     Show all 9 Subjects
Abstract:
... The production of chemicals and fuels from renewable resources using engineered microbes is an attractive alternative for current fossil-dependent industries. Metabolic engineering has contributed to pathway engineering for the production of chemicals and fuels by various microorganisms. Recently, dynamic metabolic engineering harnessing synthetic biological tools has become a next-generation stra ...
DOI:
10.1016/j.jbiosc.2021.09.009

11. Associations of prepubertal urinary phthalate metabolite concentrations with pubertal onset among a longitudinal cohort of boys

Author:
Jane S. Burns; Oleg Sergeyev; Mary M. Lee; Paige L. Williams; Lidia Mínguez-Alarcón; Bora Plaku-Alakbarova; Sergey Sokolov; Sergey Kovalev; Holger M. Koch; Albert T. Lebedev; Russ Hauser; Susan A. Korrick; for the Russian Children's Study
Source:
Environmental research 2022 v.212 pp. 113218
ISSN:
0013-9351
Subject:
isotope dilution technique,   etc   ; boys; genitalia; hormone antagonists; males; medical history; metabolites; phthalates; puberty; research; specific gravity; testes; urine;     Show all 13 Subjects
Abstract:
... Although phthalate exposures have been associated with adverse effects on male reproductive health, few studies have explored longitudinal associations with male pubertal development. We examined the association of prepubertal urinary concentrations of phthalate metabolites with age at pubertal onset in a prospective cohort of Russian boys. At enrollment at ages 8–9 years, medical history, dietary ...
DOI:
10.1016/j.envres.2022.113218

12. Evaluation of different internal standardization approaches for the quantification of melatonin in cell culture samples by multiple heart-cutting two dimensional liquid chromatography tandem mass spectrometry

Author:
Amanda Suárez Fernández; Adriana González Gago; Francisco Artime Naveda; Javier García Calleja; Anna Zawadzka; Zbigniew Czarnocki; Juan Carlos Mayo Barrallo; Rosa M. Sainz Menéndez; Pablo Rodríguez-González; J. Ignacio García Alonso
Source:
Journal of chromatography 2022 v.1663 pp. 462752
ISSN:
0021-9673
Subject:
isotope dilution technique,   etc   ; cell culture; humans; ionization; isotope labeling; liquid chromatography; melatonin; metabolites; prostatic neoplasms; tandem mass spectrometry;     Show all 10 Subjects
Abstract:
... We evaluate here different analytical strategies for the chromatographic separation and determination of N-acetyl-5-methoxytryptamine (MEL) and its oxidative metabolites N1-acetyl-N2-formyl-5-methoxykynuramine (AFMK), N1-acetyl-5-methoxykynuramine (AMK) and cyclic 3-hydroxymelatonin (c3OHM) in cell culture samples. Two dimensional liquid chromatography (2D-LC) in the multiple heart-cutting mode wa ...
DOI:
10.1016/j.chroma.2021.462752

13. Development of analytical methods to study the effect of malting on levels of free and modified forms of Alternaria mycotoxins in barley

Author:
Sophie Scheibenzuber; Fabian Dick; Marina Bretträger; Martina Gastl; Stefan Asam; Michael Rychlik
Source:
Mycotoxin research 2022 v.38 no.2 pp. 137-146
ISSN:
0178-7888
Subject:
isotope dilution technique,   etc   ; Alternaria; altenuene; barley; chemical species; liquid chromatography; malt; research; stable isotopes; tandem mass spectrometry; tenuazonic acid;     Show all 11 Subjects
Abstract:
... A liquid chromatography tandem mass spectrometry (LC–MS/MS) multi-mycotoxin method was developed for the analysis of the Alternaria toxins alternariol (AOH), alternariol monomethyl ether (AME), tentoxin (TEN), altertoxin I (ATX I), altertoxin II (ATX II), alterperylenol (ALTP), and altenuene (ALT), as well as the modified toxins AOH-3-glucoside (AOH-3-G), AOH-9-glucoside (AOH-9-G), AME-3-glucoside ...
DOI:
10.1007/s12550-022-00455-1

14. Determination of lithium in human serum by isotope dilution atomic absorption spectrometry

Author:
Alexander Winckelmann; Dalia Morcillo; Silke Richter; Sebastian Recknagel; Jens Riedel; Jochen Vogl; Ulrich Panne; Carlos Abad
Source:
Analytical and bioanalytical chemistry 2022 v.414 no.1 pp. 251-256
ISSN:
1618-2642
Subject:
isotope dilution technique,   etc   ; analytical chemistry; atomic absorption spectrometry; blood serum; digestion; drugs; humans; lanthanum; lithium; mass spectrometry; therapeutics; toxicity; wavelengths;     Show all 13 Subjects
Abstract:
... The therapeutic dose of lithium (Li) compounds, which are widely used for the treatment of psychiatric and hematologic disorders, is close to its toxic level; therefore, drug monitoring protocols are mandatory. Herein, we propose a fast, simple, and low-cost analytical procedure for the traceable determination of Li concentration in human serum, based on the monitoring of the Li isotope dilution t ...
DOI:
10.1007/s00216-021-03636-6

15. Development of a certified reference material for the determination of polycyclic aromatic hydrocarbons (PAHs) in rubber toy

Author:
Thomas Sommerfeld; Christian Jung; Juliane Riedel; Tatjana Mauch; Andreas Sauer; Matthias Koch
Source:
Analytical and bioanalytical chemistry 2022 v.414 no.15 pp. 4369-4378
ISSN:
1618-2642
Subject:
isotope dilution technique,   etc   ; analytical chemistry; carcinogenicity; chemical safety; gas chromatography-mass spectrometry; quality control; reference standards; rubber; stable isotopes; Germany;     Show all 10 Subjects
Abstract:
... Polycyclic aromatic hydrocarbons (PAHs) are a large group of priority organic pollutants, which contaminate environmental compartments, food, and consumer products as well. Due to their frequent occurrence associated with elevated levels of PAHs, plastic and rubber parts of consumer products and toys are particular sources of exposure. Although European maximum levels exist for eight carcinogenic ...
DOI:
10.1007/s00216-021-03796-5

16. Development of human serum matrix-based unconjugated estriol-certified reference material by recommended ID-LC-MS/MS reference method

Author:
Qiaoxuan Zhang; Kai Bai; Meiran Wu; Haibiao Lin; Jun Yan; Min Zhan; Fen Ouyang; Peifeng Ke; Liqiao Han; Junhua Zhuang; Xianzhang Huang
Source:
Analytical and bioanalytical chemistry 2022 v.414 no.7 pp. 2523-2531
ISSN:
1618-2642
Subject:
isotope dilution technique,   etc   ; analytical chemistry; blood serum; estriol; humans; immunoassays; liquid chromatography; medicine; metrology; tandem mass spectrometry; traceability; uncertainty; China;     Show all 13 Subjects
Abstract:
... To solve long-term lack of traceability of commercial calibrator kits and standardize clinical routine assays, we developed a human serum matrix-based unconjugated estriol (uE3) reference material (RM) with five concentration gradients. The RMs of uE3 were certified by the National Institute of Metrology (NIM) with the codes of GBW (E) 091048, GBW (E) 091049, GBW (E) 091050, GBW (E) 091051, and GB ...
DOI:
10.1007/s00216-022-03896-w

17. Arbuscular mycorrhizal fungi-mediated biologically fixed N transfer from Vachellia seyal to Sporobolus robustus

Author:
Fatoumata Fall; Dieynaba Ndoye; Antoine Galiana; Diégane Diouf; Amadou Mustapha Bâ
Source:
Symbiosis 2022 v.86 no.2 pp. 205-214
ISSN:
0334-5114
Subject:
isotope dilution technique,   etc   ; Ensifer; Rhizophagus irregularis; Sporobolus; Vachellia; exudation; greenhouses; hyphae; intercropping; nitrogen content; nitrogen fixation; nylon; plant growth; polymethylmethacrylate; soil; vesicular arbuscular mycorrhizae;     Show all 16 Subjects
Abstract:
... This study aimed to investigate the role of arbuscular mycorrhizal (AM) fungi on biological N fixation in Vachellia seyal and transfer of fixed N₂ from V. seyal to intercropped Sporobolus robustus under greenhouse conditions. Both plants were grown individually in pots to prevent root contact (“Solid barrier” treatment) or together in two-compartment containers delimited by a plexiglass plate with ...
DOI:
10.1007/s13199-022-00833-4

18. Sediment organic matter properties facilitate understanding nitrogen transformation potentials in East African lakes

Author:
Xiaolong Yao; Zhonghua Zhao; Jianjun Wang; Qiqi Ding; Minglei Ren; Ismael Aaron Kimirei; Lu Zhang
Source:
Science of the total environment 2022 v.841 pp. 156607
ISSN:
0048-9697
Subject:
isotope dilution technique,   etc   ; ammonium; anaerobic ammonium oxidation; carbon; denitrification; environment; humification; lakes; mineralization; nitrate reduction; nitrogen; nitrogen cycle; organic matter; phosphates; sediments; Kenya; Tanzania;     Show all 17 Subjects
Abstract:
... East African lakes include the most productive and alkaline lake group in the world. Yet, they generally receive fewer nutrient inputs than the densely populated subtropical and temperate lakes in the northern hemisphere. In these lakes with insufficient supplies of inorganic nitrogen, the mineralization of benthic organic matter can play an important role in driving the nutrient cycle and nitroge ...
DOI:
10.1016/j.scitotenv.2022.156607

19. A fit-for-purpose copper speciation method for the determination of exchangeable copper relevant to Wilson’s disease

Author:
M. Estela del Castillo Busto; Susana Cuello-Nunez; Christian Ward-Deitrich; Tim Morley; Heidi Goenaga-Infante
Source:
Analytical and bioanalytical chemistry 2022 v.414 no.1 pp. 561-573
ISSN:
1618-2642
Subject:
isotope dilution technique,   etc   ; albumins; analytical chemistry; anion exchange; atomic absorption spectrometry; blood serum; clinical trials; copper; drugs; high performance liquid chromatography; humans; quality control; ultrafiltration;     Show all 13 Subjects
Abstract:
... Exchangeable copper (CuEXC), mainly comprised copper (Cu) bound to albumin, has been proposed as a specific marker of Cu overload in Wilson’s disease (WD). To the author’s knowledge, there are no methods capable of determining reliably CuEXC to meet the requirements and challenges faced by a clinical trial. The present work describes a novel speciation strategy for the determination of the main Cu ...
DOI:
10.1007/s00216-021-03517-y

20. A nested case-control study of serum polychlorinated biphenyls and papillary thyroid cancer risk among U.S. military service members

Author:
Haoran Zhuo; Huang Huang; Andreas Sjodin; Lan Jin; Shuangge Ma; Hristina Denic-Roberts; Joshua L. Warren; Richard Jones; Mark Davis; Peiyuan Sun; Herbert Yu; Mary H. Ward; Robert Udelsman; Yawei Zhang; Jennifer A. Rusiecki
Source:
Environmental research 2022 v.212 pp. 113367
ISSN:
0013-9351
Subject:
isotope dilution technique,   etc   ; Bayesian theory; bioaccumulation; blood serum; case-control studies; dose response; gas chromatography; histology; mass spectrometry; models; regression analysis; research; risk; thyroid neoplasms;     Show all 14 Subjects
Abstract:
... Although polychlorinated biphenyls (PCBs) were banned decades ago, populations are continuously exposed to PCBs due to their persistence and bioaccumulation/biomagnification in the environment. Results from limited epidemiologic studies linking PCBs to thyroid cancer have been inconclusive. This study aimed to investigate the association between individual PCBs and PCB mixture and papillary thyroi ...
DOI:
10.1016/j.envres.2022.113367