Premium
The interconversion of δ 2 H values of collagen between thermal conversion reactor configurations
Author(s) -
Reynard Linda M.,
Ryan Saskia E.,
Tuross Noreen
Publication year - 2019
Publication title -
rapid communications in mass spectrometry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.528
H-Index - 136
eISSN - 1097-0231
pISSN - 0951-4198
DOI - 10.1002/rcm.8396
Subject(s) - chemistry , chromium , yield (engineering) , packed bed , carbon fibers , hydrogen , analytical chemistry (journal) , mass spectrometry , nitrogen , nuclear chemistry , chromatography , organic chemistry , materials science , composite material , composite number
Rationale Different thermal conversion reactor packings result in distinct δ 2 H values in nitrogen‐containing materials, such as bone collagen. An older ‘traditional’ glassy carbon packing method causes incomplete conversion of N‐containing samples into H 2 gas, resulting in altered δ 2 H values compared with the complete conversion of hydrogen obtained with a chromium‐packed reactor. Given that δ 2 H values from collagen are gaining importance in palaeoecological and archaeological studies, a determination of the relationship between δ 2 H values produced with a glassy‐carbon‐packed and a chromium‐packed reactor is needed. Methods We obtained δ 2 H values (normalized on the VSMOW‐SLAP scale) from both glassy‐carbon‐packed (GP) and chromium‐packed (Cr) reactor configurations from bone collagen ( n = 231) from a variety of archaeological sites, using a High‐Temperature Conversion Elemental Analyzer (TC/EA) coupled to a Delta Plus XP isotope ratio mass spectrometer. Results δ 2 H values from both methods are linearly correlated (r 2 = 0.934) and yield the following interconversion equation, δ 2 H(Cr) = 1.054 δ 2 H(GP) + 11.6‰ (95% conf. slope 1.020–1.090, intercept 10.6–12.6), and a mean difference of δ 2 H(Cr) – δ 2 H(GP) = 10.1‰ (1 sd 5.2, 1 se 0.3, n = 231). Conclusions We recommend adopting this interconversion between δ 2 H values produced with a glassy‐carbon‐packed and chromium‐packed reactor for bone collagen only, with appropriate propagation of uncertainty.