Research Laboratory for Archaeology and the History of Art, Dyson Perrins Building, South Parks Road, Oxford OX1 3QY, UK.
Rapid Commun Mass Spectrom. 2010 Mar 15;24(5):541-8. doi: 10.1002/rcm.4398.
We report a novel method for the chromatographic separation and measurement of stable carbon isotope ratios (delta(13)C) of individual amino acids in hair proteins and bone collagen using the LC-IsoLink system, which interfaces liquid chromatography (LC) with isotope ratio mass spectrometry (IRMS). This paper provides baseline separation of 15 and 13 of the 18 amino acids in bone collagen and hair proteins, respectively. We also describe an approach to analysing small hair samples for compound-specific analysis of segmental hair sections. The LC/IRMS method is applied in a historical context by the delta(13)C analysis of hair proteins and bone collagen recovered from six individuals from Uummannaq in Greenland. The analysis of hair and bone amino acids from the same individual, compared for the first time in this study, is of importance in palaeodietary reconstruction. If hair proteins can be used as a proxy for bone collagen at the amino acid level, this validates compound-specific isotope studies using hair as a model for palaeodietary reconstruction. Our results suggest that a small offset observed in the bulk delta(13)C values of the hair and bone samples may be attributed to two factors: (i) amino acid compositional differences between hair and bone proteins, and (ii) differential turnover rates of the tissues and the amino acid pools contributing to their synthesis. This application proposes that hair may be a useful complementary or alternative source of compound-specific paleodietary information.
我们报告了一种使用 LC-IsoLink 系统对毛发蛋白质和骨胶原中的稳定碳同位素比值(δ¹³C)进行色谱分离和测量的新方法,该系统将液相色谱(LC)与同位素比质谱(IRMS)相连接。本文分别实现了骨胶原和毛发蛋白质中 18 种氨基酸中的 15 种和 13 种的基线分离。我们还描述了一种用于分析小毛发样本的方法,以对毛发分段进行特定化合物的分析。该 LC/IRMS 方法应用于历史背景下,对来自格陵兰乌玛纳克的 6 个人的毛发蛋白质和骨胶原进行了 δ¹³C 分析。本研究首次对同一个体的毛发和骨氨基酸进行了分析,这对于古饮食重建具有重要意义。如果毛发蛋白质可以在氨基酸水平上作为骨胶原的替代物,那么这将验证使用毛发作为古饮食重建模型的特定化合物同位素研究的有效性。我们的结果表明,毛发和骨样本的总 δ¹³C 值中观察到的小偏移可能归因于两个因素:(i)毛发和骨蛋白质中氨基酸组成的差异,以及(ii)组织和参与其合成的氨基酸库的周转率不同。本应用表明,毛发可能是一种有用的补充或替代特定化合物古饮食信息的来源。