Preparative separation of underivatized amino acids for compound‐specific stable isotope analysis and radiocarbon dating of hydrolyzed bone collagen

Abstract

Analysis of stable and radioactive isotopes from bone collagen provides useful information to archaeologists about the origin and age of bone artifacts. Isolation and analysis of single amino acids from the proteins can provide additional and more accurate information by removing contamination and separating a bulk isotope signal into its constituent parts. In this paper, we report a new method for the separation and isolation of underivatized amino acids from bone collagen, and their analysis by isotope ratio MS and accelerator MS. RP chromatography is used to separate the amino acids with nonpolar side chains, followed by an ion pair separation to isolate the remaining amino acids. The method produces single amino acids with little or no contamination from the separation process and allows for the measurement of accurate stable isotope ratios and pure samples for radiocarbon dating.

Single amino acid radiocarbon dating of Upper Paleolithic modern humans

“…The amino acid retention times were identified using standards, and spiking natural samples confirmed these retention times in archaeological samples. Detection by UV absorbance (32)(33)(34) and LC/MS analysis of selected amino acid fractions was used to confirm identification of peaks by mass. It is crucial that laboratory-derived carbonaceous material be kept as close to zero as possible.…”

Status Report of the New AMS 14C Sample Preparation Lab of the Hertelendi Laboratory of Environmental Studies (Debrecen, Hungary)

“…The organic fraction of the bone is also influenced by interactions with humic substances penetrating into the porous material of the bone, where they may become adsorbed or interact with the intrinsic degradation processes occurring in the bone, known as Maillard processes (van Klinken and Hedges 1995). Depending on local environmental and soil characteristics, these factors may increase or decrease the apparent 14 C age of bone collagen (Stafford et al 1988;Tripp et al 2006).…”

Monitoring the Presence of Humic Substances in Wool and Silk by the Use of Nondestructive Fluorescence Spectroscopy: Quality Control for14C Dating of Wool and Silk

“…Compound-specific 14 C dating of individual amino acids (Van Klinken and Cook 1990;Tripp et al 2006;McCullagh et al 2010) of the silk/wool protein can be a potential method for dating proteinic textiles showing HS contamination. However, the conventional pretreatment method yields reliable 14 C dates of proteinic textiles, wherein no HSs were observed with spectrofluorescence.…”