scholarly journals Sr Isotopic Composition of NIES Certified Reference Material No. 28 Urban Aerosols

2021 ◽  
Vol 2 ◽  
Author(s):  
Akane Yamakawa ◽  
Kimiyo Nagano ◽  
Miyuki Ukachi ◽  
Kaoru Onishi ◽  
Katsuyuki Yamashita ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Reference Material ◽  
Isotopic Composition ◽  
Certified Reference Material ◽  
Cation Exchange Resin ◽  
Information Value ◽  
Ionization Mass ◽  
Beijing City ◽  
Urban Aerosols ◽  
Isotopic Compositions

An interlaboratory study of the National Institute for Environmental Studies (NIES) certified reference material (CRM) No. 28 Urban Aerosols collected from the filters of a central ventilating system in a building in the Beijing city center from 1996 to 2005 was performed to obtain an information value of the Sr isotopic composition. The Sr isotopic composition was measured using multi-collector-inductively coupled plasma-mass spectrometry (MC-ICP-MS) to confirm the CRM’s within- and between-bottle homogeneity, and the results showed a 87Sr/86Sr ratio of 0.710227 ± 0.000019 (2SD, n = 18). The Sr isotopic compositions were intercompared using thermal ionization mass spectrometry (TIMS), which showed good agreement with values obtained at NIES. Subsequently, a consistent 87Sr/86Sr ratio was observed between two dissolution (hotplate vs. high-pressure bomb) and Sr separation (Sr spec resin vs. cation exchange resin) methods. To validate and reproduce the accuracy of our analytical methods, the Sr isotopic compositions of secondary reference materials, JB-1b and JA-2, were also measured. Our results showed that NIES CRM No. 28 is appropriate for the quality control of Sr isotope measurements of particulate matter analyses for environmental and geochemical studies.

scholarly journals Hg isotopic composition and total Hg mass fraction in NIES Certified Reference Material No. 28 Urban Aerosols

2020 ◽  
Vol 412 (19) ◽  
pp. 4483-4493
Author(s):  
Akane Yamakawa ◽  
Sylvain Bérail ◽  
David Amouroux ◽  
Emmanuel Tessier ◽  
Julien Barre ◽  
...  
Keyword(s):  
Reference Material ◽  
Isotopic Composition ◽  
Certified Reference Material ◽  
Mass Fraction ◽  
Urban Aerosols ◽  
Total Hg

scholarly journals Characterization of a New Certified Reference Material for Human Cardiac Troponin I

2006 ◽  
Vol 52 (2) ◽  
pp. 212-219 ◽  
Author(s):  
David M Bunk ◽  
Michael J Welch
Keyword(s):  
Mass Spectrometry ◽  
Reference Material ◽  
Certified Reference Material ◽  
Cardiac Troponin ◽  
Troponin I ◽  
Reversed Phase ◽  
Cardiac Troponin I ◽  
Reference Concentration ◽  
System Of Units

Abstract Background: To address the continuing need for the standardization of clinical human cardiac troponin I (cTnI) assays, NIST, with the assistance of the AACC/IFCC Cardiac Troponin I Standardization Committee, has developed a new certified reference material, Standard Reference Material (SRM) 2921: Human Cardiac Troponin Complex. Methods: The concentration of cTnI in SRM 2921 was determined through a combination of reversed-phase liquid chromatography (LC) with ultraviolet detection and amino acid analysis. Characterization of the intact troponin subunits was accomplished through reversed-phase LC coupled with mass spectrometry. Posttranslational modifications to the cTnI in SRM 2921 were investigated by combining proteolytic digestion with matrix-assisted laser desorption/ionization mass spectrometry. Additionally, reference concentration values for cTnT and cTnC were also determined. Results: The concentration of human cTnI in SRM 2921 is 31.2 (1.4) mg/L (where 1.4 mg/L is the uncertainty at a 95% level of confidence), as certified through a method that provides traceability to the International System of Units (SI). Reference concentration values of the cTnT and cTnC subunits were determined to be 36.9 (3.8) mg/L and 24.2 (1.3) mg/L, respectively. Conclusions: This first cTnI reference material should provide SI traceability to clinical cTnI assays once commutability has been validated, and could assist in the international harmonization of cTnI assays as a tool for understanding the underlying causes of interassay variability.

scholarly journals Further Characterization of the RW-1 Monazite: A New Working Reference Material for Oxygen and Neodymium Isotopic Microanalysis

Minerals ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 583 ◽  
Author(s):  
Wu ◽  
Li ◽  
Ling ◽  
Yang ◽  
Li ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Reference Material ◽  
Inductively Coupled Plasma ◽  
Secondary Ion Mass Spectrometry ◽  
Hydrothermal Activity ◽  
Ionization Mass ◽  
Nd Isotopes ◽  
Inductively Coupled ◽  
The Matrix ◽  
Plasma Mass Spectrometry

The oxygen (O) and neodymium (Nd) isotopic composition of monazite provides an ideal tracer of metamorphism and hydrothermal activity. Calibration of the matrix effect and monitoring of the external precision of monazite O–Nd isotopes with microbeam techniques, such as secondary ion mass spectrometry (SIMS) and laser ablation-multicollector-inductively coupled plasma-mass spectrometry (LA-MC-ICPMS), require well-characterized natural monazite standards for precise microbeam measurements. However, the limited number of standards available is impeding the application of monazite O–Nd isotopes. Here, we report on the RW-1 monazite as a potential new working reference material for microbeam analysis of O–Nd isotopes. Microbeam measurements by electron probe microanalysis (EPMA), SIMS, and LA-MC-ICPMS at 10–24 µm scales have confirmed that it is homogeneous in both elemental and O–Nd isotopic compositions. SIMS measurements yield δ18O values consistent, within errors, with those obtained by laser fluorination techniques. Precise analyses of Nd isotope by thermal ionization mass spectrometry (TIMS) are consistent with mean results of LA-MC-ICPMS analyses. We recommend δ18O = 6.30‰ ± 0.16‰ (2SD) and 143Nd/144Nd = 0.512282 ± 0.000011 (2SD) as being the reference values for the RW-1 monazite.

Sign in / Sign up

Export Citation Format

Share Document