Identification by GC-FID and GC-MS of amino acids, fatty and bile acids in binding media used in works of art

Characterisation of proteinaceous binders in artistic paintings by chromatographic techniques

“…Their mass spectra show a very simple fragmentation pattern and are normally dominated by a large abundance of ions with m/z equal to M -57 + (loss of a tert-butyl group), which enable molecular weight determination and are very suitable for performing quantitative analysis by Selected Ion Monitoring. c) Derivatisation with ethyl chloroformiate in ethanol/ water/pyridine [23,24,29,61]. The reaction, which takes place in one step, in only a few seconds and in the presence of water, acts on both amino and hydroxyl groups.…”

“…egg, animal glue and casein. Different ratios have been proposed [25,30,31,36,38,61,65], for example gly/glu, gly/asp, pro/asp, glu/pro, glu/asp, glu/ ala, ala/pro, ala/gly. Since the methods are usually based on the fact that animal glue contains substantially higher amounts of gly with respect to egg and milk, while casein contains higher amounts of glu with respect to egg, gly and glu are always included in the most significant ratios.…”

An evaluation of GC‐MS and HPLC‐FD methods for analysis of protein binders in paintings

“…Derivatizations with ethyl chloroformate have been used in analyses of binders, e. g. in refs. [7,8,13,14].…”

Application of peptide mass mapping on proteins in historical mortars

“…As there is usually extremely low content of the proteinaceous additives in mortars, the reliable identification of them represents a complicated analytical problem. In most of common analytical methods the identification of proteins is based on monitoring of the ratios of certain amino acids [4][5][6][7][8]; these parameters are not specific enough for individual proteins. Moreover, the protein decomposition is time consuming and the determination of amino acids ratios is not sufficiently reliable because of their modification and losses under the hydrolysis conditions.…”