Automation of boron chromatographic purification for δ 11 B analysis of coral aragonite.

Autor: de la Vega E; School of Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Southampton, SO14 3ZH, UK., Foster GL; School of Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Southampton, SO14 3ZH, UK., Martínez-Botí MA; School of Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Southampton, SO14 3ZH, UK., Anagnostou E; School of Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Southampton, SO14 3ZH, UK.; GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstraße 1-3, 24148, Kiel, Germany., Field MP; Elemental Scientific, Inc, 7277 World Communications Drive, Omaha, NE, 68122, USA., Kim MH; Elemental Scientific, Inc, 7277 World Communications Drive, Omaha, NE, 68122, USA., Watson P; Elemental Scientific, Inc, 7277 World Communications Drive, Omaha, NE, 68122, USA., Wilson PA; School of Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Southampton, SO14 3ZH, UK.
Jazyk: angličtina
Zdroj: Rapid communications in mass spectrometry : RCM [Rapid Commun Mass Spectrom] 2020 Jun 15; Vol. 34 (11), pp. e8762.
DOI: 10.1002/rcm.8762
Abstrakt: Rationale: To detect the small changes in past pH , the boron isotope ratio of coral carbonates, expressed as the δ 11 B value, needs to be both precise and accurate (2sd <<1‰). Boron measurements by Multi-Collector Inductively Coupled Plasma Mass Spectrometry (MC-ICPMS) require the boron to be carefully purified before analysis, which is time consuming, and requires specialist training. Here, we use the prepFAST-MC method that enables the automatic extraction of B (up to 25 ng load) from a CaCO 3 matrix.
Methods: Samples were purified using the prepFAST-MC automated system with a ~25-μL column of Amberlite IRA743 resin. Boron isotope measurements were performed by MC-ICPMS. The effects of matrix load, speed of sample loading onto the column, and blank contamination were tested to evaluate the effects on the purification process. The optimised protocol was tested on various standards and samples of aragonite corals.
Results: The blank contribution for the approach is ~60 pg and is negligible given our sample size (<0.2% sample size). Efficiency of matrix removal is demonstrated with the addition of up to 1.6 mg of dissolved low-B calcium carbonate to NIST SRM 951 with no impact on the accuracy of δ 11 B values. The Japanese Geological Survey Porites reference material JCp-1, boric acid standard NIST SRM 951, and seawater, all processed on the prepFAST-MC system, give δ 11 B values within error of literature values (δ 11 B JCp-1 = 24.31 ± 0.20‰ (2sd, n = 20); δ 11 B NIST 951 = -0.02 ± 0.15‰ (2sd, n = 13) and δ 11 B Seawater = 39.50 ± 0.06‰ (2sd, n = 2)). Results obtained from the coral Siderastrea siderea purified with the prepFAST-MC system show an average offset from the manual ion-exchange protocols of Δδ 11 B = 0.01 ± 0.28‰ (2sd, n = 12).
Conclusions: Our study demonstrates the capacity of the prepFAST-MC method to generate accurate and reproducible δ 11 B values for a range of materials, without fractionation, with efficient matrix removal and with negligible blank contribution.
(© 2020 The Authors. Rapid Communications in Mass Spectrometry published by John Wiley & Sons Ltd.)
Databáze: MEDLINE
Externí odkaz: