Gas Chromatographic Analysis of Amino Acids As Ethyl Chloroformate Derivatives. Part 1, Composition of Proteins Associated with Art Objects and Monuments

Abstract

Gas chromatography has long been used as a means of identifying proteins in acid hydrolysates of paints and adhesives on the basis of their amino acid composition. Existing procedures for amino acid derivatization can, however, take up to 4 hours per analysis, whereas a new procedure employed at the Getty Conservation Institute can be carried out in less than 20 minutes. This procedure involves the formation of N(O,S)-ethoxycarbonyl ethyl esters of amino acids using ethyl chloroformate and then a separation on an HP-INNOWAX capillary column. This procedure was employed to analyze samples from the binding media library at the Getty Conservation Institute, and amino acid compositions were tabulated for various proteins that could be used for identification purposes.