Development of Two New Copper Isotope Standard Solutions and their Copper Isotopic Compositions

Abstract

and copper wire, were dissolved in 1000 ml Teflon® bottles, to result in 200 µg ml -1 stock solutions (hereafter referred to as NWU-Cu-A and NWU-Cu-B), and cryogenically stored. The Cu isotopic compositions of the two samples were determined in three different laboratories using multi-collector inductively coupled plasma-mass spectrometry, and the Cu isotopic compositions obtained from the standard-sample bracketing method were consistent within the two standard deviation (2s) range. The Cu isotopic compositions of the NWU-Cu-A and NWU-Cu-B standard solutions were δ 65 Cu = +0.91 ± 0.03‰ (2s, n = 42) and δ 65 Cu = -0.05 ± 0.03‰ (2s, n = 49), respectively, relative to the reference material NIST NBS 976.

Copper Isotope Ratio Measurements of Cu-Dominated Minerals Without Column Chromatography Using MC-ICP-MS

“…The results are shown in Table 4. Relative to NIST SRM 976, the NWU-Cu-A solution doped with matrix elements yielded a mean value of 0.91 ± 0.05‰ (2s, n = 5), identical with the reported value of the pure solution (Yuan et al, 2017). The δ 65 Cu ratios of GEMOC Cu, GSB-Cu, and CAGS Cu standard solutions are identical with the previously reported values within 2s uncertainties (Hou et al, 2008;Liu et al, 2014;Yuan et al, 2017;Li et al, 2019).…”

“…Precisions are expressed as 2 standard deviations (2s), which were calculated on the basis of three or four replicate measurements. The dotted line indicates the reference value obtained by Yuan et al (2017). The gray area represents the 0.05‰ uncertainty range.…”

“…Errors are presented at the 2s level, which was obtained by measuring three times. The dotted line indicates the δ 65 Cu reference value acquired by Yuan et al (2017). The gray region expresses the 0.02‰ uncertainty range.…”

Geostandards and Geoanalytical Research Bibliographic Review 2017

“…NWU‐Cu‐A and NWU‐Cu‐B are standard solutions for the analysis of Cu isotopic compositions (Yuan et al . ), and Nonose et al . () at the National Metrology Institute of Japan (NMIJ) introduce a candidate RM for Pb isotopes.…”

Cu Isotopic Composition in Surface Environments and in Biological Systems: A Critical Review

“…The Cu isotope data for a sample are expressed as δ 65 Cu (‰) notation, with a comparison to the 65 Cu/ 63 Cu ratio of the Cu standard solution, calculated by the formula: δ 65 Cu = [( 65 Cu/ 63 Cu) sample /( 65 Cu/ 63 Cu) standard − 1] × 1000 where standard represents the international reference material NIST SRM 976 [6]. Recently, researchers have made efforts to improve the measurement precision, in different analytical aspects such as Cu separation from sample matrix [6,11,23,24], highly purified Cu standard development [10,13,27,28], and mass discrimination correction [10,29,30,31]. …”