High‐precision determination of 18O/16O ratios of silver phosphate by EA‐pyrolysis‐IRMS continuous flow technique

• DOI: 10.1002/jms.1130
• Publication Date: 2006-12-06T10:50:10Z
• Authors: Christophe Lécuyer; François Fourel; François Martineau; Romain Amiot; Aurélien Bernard; Valérie Daux; Gilles Escarguel; John Morrison
• Keywords: Ammonium dihydrogen phosphate; Isotope-ratio mass spectrometry

Abstract A high‐precision, and rapid on‐line method for oxygen isotope analysis of silver phosphate is presented. The technique uses high‐temperature elemental analyzer (EA)‐pyrolysis interfaced in continuous flow (CF) mode to an isotopic ratio mass spectrometer (IRMS). Calibration curves were generated by synthesizing with a 13‰ spread δ 18 O values. materials obtained reacting dissolved potassium dihydrogen (KH 2 PO 4 ) water samples various compositions at 373 K. Validity the was tested comparing results those classical off‐line sample preparation dual inlet measurement. In addition, precipitates prepared from collection biogenic apatites known values ranging 12.8 29.9‰ (V–SMOW). Reproducibility ± 0.2‰ EA‐Py‐CF‐IRMS sizes range 400–500 µg. Both natural synthetic are remarkably well correlated conventional O/ 16 determinations. Silver very stable material easy degas and, thus, could be considered as good candidate become reference determination ratios pyrolysis. Copyright © 2006 John Wiley & Sons, Ltd.