Effects of demineralization protocols on hydrogen and oxygen isotope ratios in fossil bone collagen

Bibliographic Data

ID24033445
AuthorsLinda M Reynard (0000-0001-5732-1532, Boise State University, corresponding author)
Year2026
Volume75
Pages106004
Publication date2026-11-01
Peer ReviewedYes
Open AccessYes
TypeARTICLE
VenueJournal of Archaeological Science Reports (JOURNAL)
Journal identifiersISSN: 2352-409X • E-ISSN: 2352-4103
PublisherElsevier BV (PUBLISHER)
DOI10.1016/j.jasrep.2026.106004
OpenAlexW7202287873
LanguageEN
References cited26

The effect of three commonly used preparation protocols on bone collagen δ 2 H and δ 18 O values was investigated, using six generally well-preserved faunal bones (cattle, bison, horse) ranging in age from the Holocene to Late Pleistocene. The treatments tested were ethylene diamine tetraacetic acid demineralization without gelatinization and hydrochloric acid demineralization with and without gelatinization. There are significant shifts in δ 18 O values among preparation methods. No systematic shifts in bone collagen δ 2 H values were noted among the three treatments, and most offsets were low (< 2–3 ‰) and smaller than typical measurement uncertainties. A few sample/treatment combinations yielded slightly higher inter-treatment δ 2 H differences (∼ 5–7 ‰). Lower mass fraction of hydrogen in HCl-demineralized samples suggests (greater) molecular alterations to the collagen structure, with possibilities including deamidation and/or peptide bond hydrolysis. The use of 2 H-enriched water ( Δ 2 H + 258 ‰) in the demineralization and gelatinization solutions systematically elevated resultant collagen δ 2 H values; however, given the expected water isotopic variation among labs this should be an insignificant source of inter-lab variation. The δ 2 H values appear to be fairly robust in these samples. Further work across a greater range of samples from different burial environments and diagenetic states is recommended.

Demineralization · Diagenesis · Hyaluronic acid · Hydrogen · Isotope · Isotope analysis · Isotope-ratio mass spectrometry · Isotopes of oxygen · Archaeology and ancient environmental studies · Collagen: Extraction and Characterization · Pleistocene-Era Hominins and Archaeology