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.

The reconstruction of ancient diets using isotopic measurements of bone collagen, and other tissues, which survive in archaeological contexts, relies on known isotopic relationships between diet and body tissues. Examination of these relationships often requires the study of modern human and animal subjects. While hair keratin can act as a useful proxy for bone collagen in isotopic studies on living humans, where it is inappropriate to sample tissues such as collagen, it can, in addition, act as a chronological indicator of dietary change. This study investigates hair keratin delta13C values from current residents of the UK and the USA. Residents in the USA showed a clear bulk hair delta13C enrichment of approximately 3 per thousand over UK individuals, attributed to an elevated C4 dietary input from maize fed to livestock in North America. The keratin delta13C of subjects who moved between the UK and USA showed a pronounced change after relocation, taking approximately 4 months to reach isotopic equilibrium. To investigate these differences further, we measured delta13C values of dispensable and indispensable amino acids as a group, and selected individual amino acids. As a group, enrichment of dispensable amino acids compared with indispensable amino acids occurred in samples from both continents, averaging 7.2 per thousand in the UK and 7.9 per thousand in the USA. Dispensable and indispensable amino acids, as well as all individual amino acids measured, were enriched in samples from the USA compared with those from the UK.

[reaction: see text] Solid functionalized porous monolithic disks with reactive polymer chains grafted to their inner pore surface have been developed for scavenging excess reagents from reaction mixtures. A poly(chloromethylstyrene-co-divinylbenzene) monolith was cut into disks and activated by graft polymerizing 4-vinyl-2,2-dimethylazlactone to its pore surface. In contrast to the direct copolymerization of reactive monomers, grafting increases the accessibility of the reactive groups. Application of the reactive disks is demonstrated in the scavenging of excess amines from reaction mixtures in different solvents.

Polyethylene encased porous poly(chloromethylstyrene-co-divinylbenzene) disks have been prepared by polymerization in a cylindrical glass mold and cut to a disk format. Following attachment of a free radical azo initiator 4,4'-azobis(4-cyanovaleric acid) to available functionalities at the surface of the pores, the polymerization of 2-vinyl-4,4-dimethylazlactone was initiated from the surface. To avoid an undesirable increase in flow resistance and to improve the yield of grafting, divinylbenzene was added to the polymerization mixture in order to form a layer of swellable reactive polymer gel within the pores. The use of these disks as scavenging filters to remove various amines from solutions in flow-through operations was demonstrated by effective removal of amines in a very short period of time from their solutions in a variety of solvents, even including alcohols and water.

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