Matrix-matched quantitative analysis of trace-elements in calcium carbonate shells by laser-ablation ICP–MS: application to the determination of daily scale profiles in scallop shell (Pecten maximus)

Abstract

A micro-scale method has been developed for analysis of trace-element concentration profiles in the calcium carbonate shell of the Great Scallop (Pecten maximus). UV laser ablation at 266-nm coupled with ICP-MS detection was used to analyse daily calcite striae of shell samples to obtain high temporal resolution of trace element incorporation. Analysis of scallop shells was carefully examined to determine the quality of calcium carbonate ablation and calibration. An accurate external calibration method based on matrix matching was developed. Twelve sodium-free enriched calcium carbonate standards containing up to twenty-four elements were prepared, by co-precipitation with aqueous ammonia and NH(4)HCO(3), and subsequently back-calibrated in the laboratory. These CaCO(3) standards were found to be homogenous and their use enabled sensitive quantitative analysis (detection limits of a few ng g(-1)) over a wide range of concentrations (0.1 to 500 microg g(-1)). Use of these CaCO(3) standards was also evaluated by analysis of three calcium-rich certified reference materials. Because calibration was consistent with the certified results, this analytical method is a sensitive tool for analysis of environmental calcium carbonate matrices. Repeated analysis of scallop shell samples collected simultaneously at the same location showed that the trace elements are homogeneously distributed along a stria. The reliability of such in-situ records of biogenic calcium carbonate (scallop shells) is apparent from the inter-individual and inter-annual reproducibility of the trace element profiles.

Plasticity of European flounder life history patterns discloses alternatives to catadromy

“…In addition, a low volume ablation cell (3.7 cm 3 ) was used to minimize signal peak broadening and enhance the signal-to-noise ratio. Quantification of trace elements in otoliths was achieved by external calibration using a series of 13 coprecipitated carbonate pellets (Barats et al 2007) ranging from 0.1 to 500 µg g −1 . Matrix matching calibration was preferred over conventional NIST glass sample to ensure the best accuracy.…”

High frequency Barium profiles in shells of the Great Scallop <i>Pecten maximus</i>: a methodical long-term and multi-site survey in Western Europe

“…to an ICP-MS (X7 serie, Thermo Fisher). The methodology and validation were described elsewhere and summarized here (Barats et al, 2007). Samples were analysed during 2 min at a scan speed rate of 5 µm/s.…”

“…The intensity of each isotope signal was systematically normalized against the 43 Ca signal to compensate for instrumental drift and instability. An external calibration was performed with lab prepared CaCO 3 standards containing Ba concentrations ranging from 0.005 to 19.6 µg/g (Barats et al, 2007). The Ba calibration curve displayed a good linearity with a regression coefficient r 2 above 0.998 (Barats et al, 2007).…”

“…This study focuses on Ba content in the Great Scallop shell Pecten maximus (L.) to further establish how these bivalves can provide time resolved ([Ba]/[Ca]) shell profiles (daily scale) and valuable archives of environmental changes in temperate environments (Lorrain et al, 2000;Chauvaud et al, 1998Chauvaud et al, , 2005Lorrain et al, 2005;Barats, 2006;Barats et al, 2007Barats et al, , 2008Gillikin et al, 2008 ). High frequency A.…”

“…High frequency A. Barats et al: Barium uptake into the shells of the Great Scallop 159 profiles of Ba content in the calcitic shell can be determined for each individual striae using laser ablation -inductively coupled plasma -mass spectrometry (LA-ICP-MS) (Barats et al, 2007). In this paper, the significance of ([Ba]/[Ca]) shell profiles in P. maximus is first evaluated for both background concentration and episodic sharp peaks in a single scallop population from the Bay of Brest (northwest France), among different coastal sites in western Europe, and over a 7-year period (1998)(1999)(2000)(2001)(2002)(2003)(2004) 30 W) were subjected to low anthropogenic inputs.…”