High‐Precision Zinc Isotopic Measurement of Certified Reference Materials Relevant to the Environmental, Earth, Planetary and Biomedical Sciences

Abstract

The zinc (Zn) stable isotope system has emerged as a powerful tool for investigating natural and anthropogenic processes of interest to disciplines ranging from the Earth and planetary sciences to biomedical research. In nature, Zn isotopes typically fractionate (66 Zn/ 64 Zn) within the range of-1 and +1 permil (‰), and however, analytical limitations restrict the application of the Zn isotope system. Specifically, there is a lack of well-characterised matrix-matched reference materials covering most Zn isotope applications that are essential for validating laboratory performance, particularly given the contamination prone nature of Zn. Furthermore, the increasing demand for analysis of size-limited materials and sample types displaying small, sub-permil level Zn isotope variations requires improvements in measurement procedures. To address these limitations, the d 66 Zn values of two pure Zn solutions and eighteen reference materials including the previously uncharacterised RGM-2, BCR-279, DOLT-4, DOLT-5, NASS-7, SBC-1, SGR-1b, MESS-3 and HISS-1, and the understudied QLO-1, SDC-1, BCR-414, NASS-6 and COQ-1 materials are reported. Furthermore, a 70 Zn-67 Zn doublespike design has been implemented that routinely achieves intermediate measurement precision better than ± 0.02‰. This represents at least a twofold improvement when compared with other double-spike designs, providing a robust platform of d 66 Zn values required for quality control procedures.

Copper, Zinc and Lead Isotopic Delta Values and Isotope Ratios of Various Geological and Biological Reference Materials

“…The δ 66 Zn JMC values of DOLT-4, BCR-414 and BCR-279 were -0.96 AE 0.02‰ (1s), +0.29 AE 0.02‰ (1s) and +0.51 AE 0.03‰ (1s), respectively (Table 3). These values corresponded with the reported values of -1.00 AE 0.01‰ (2s) for DOLT-4, +0.29 AE 0.02‰ (2s) for BCR-414 and +0.49 AE 0.01‰ (2s) for BCR-279 by Druce et al (2020).…”

“…These values corresponded with the reported values of −1.00 ± 0.01‰ (2 s ) for DOLT‐4, +0.29 ± 0.02‰ (2 s ) for BCR‐414 and +0.49 ± 0.01‰ (2 s ) for BCR‐279 by Druce et al . (2020).…”

Application of Zn Isotope Compositions in Oysters to Monitor and Quantify Anthropogenic Zn Bioaccumulation in Marine Environments over Four Decades: A “Mussel Watch Program” Upgrade

“…The RMs MESS-3 marine sediment ( n = 9) and SRM 1566b oyster tissue ( n = 4) were prepared in replicates that followed the complete analytical protocol, i.e., sample digestion, ion-exchange chromatography, and replicated isotopic analyses. The δ 66 Zn JMC value for MESS-3 was +0.26 ± 0.06‰ (2s; n = 9), in line with the previously published value, +0.28 ± 0.02‰ (2s) . Certified reference materials for bivalve tissue matrices for Zn isotope analysis are nonexistent.…”

“…The δ 66 ZnJMC value for MESS-3 was +0.26 ±0.06‰ (2s, n = 9), in line with the previously published value, +0.28 ± 0.02‰ (2s). 54 Certified reference materials for bivalve tissues matrixes for Zn isotope analysis are inexistent. As an alternative, research groups have reported δ 66 ZnJMC values for reference materials that are commercially available.…”

Geostandards and Geoanalytical Research Bibliographic Review 2020

“…The zinc (Zn) stable isotope system is used to investigate natural and anthropogenic processes in various disciplines like Earth and planetary sciences or biomedical research. For there is a lack of well-characterised matrix-matched RMs, Druce et al (2020) have published Zn isotopic data for eighteen reference materials including many previously uncharacterised RMs. A large study on Cd isotopes with results for rock and soil RMs of different providers covering a range of -0.251 to 0.632& relative to NIST SRM 3108 has been conducted by Liu et al using a MC-ICP-MS technique with double spike correction (Liu et al 2020).…”