0000000000139742
AUTHOR
M.j Casas-catalán
Identification of lipid binders in paintings by gas chromatography
Abstract The influence of the presence and the type of pigments in the lipid binding media of paintings were studied by gas chromatography with flame ionization detector. The drying oils were linseed stand oil, poppy oil and sunflower oil, and the pigments studied were cadmium red, cobalt blue, tin white, lead white, chalk and plaster of Paris, commonly used in paintings. The results indicate that the stearic/palmitic ratio and the presence of pigments are quite stable during ageing. However, some differences in the oleic acid/palmitic acid ratio were found, depending on the type of pigment present in the lipid binding media. These variations are related to the drying effect of the pigments…
Identification by GC-FID and GC-MS of amino acids, fatty and bile acids in binding media used in works of art.
GC-FID was used as single methodology for the identification and differentiation of proteins, lipids and ox bile from binders used in artistic paintings. The samples were hydrolyzed by HCl. Subsequently, the simultaneous formation of volatile derivatives of the amino, fatty and bile acids with ethyl chloroformate was performed quickly and safely in an aqueous medium. The derivatives were separated by capillary GC and characterized by GC-MS. The ageing of drying oils was studied, identifying pelargonic acid among other degradation products. Proteinaceous and lipoid binding media were characterized by means of the quotients between the areas of the peaks for each amino or fatty acid with resp…
Analytical study of proteinaceous binding media in works of art by gas chromatography using alkyl chloroformates as derivatising agents.
In this work, we present the results obtained in an analytical study of the different types of proteinaceous binding media most commonly used in paintings, using GC-FID as the technique of analysis and GC-MS as a confirmatory technique. The application of this methodology requires prior hydrolysis of the proteins in the binding media to obtain free amino acids and then volatile derivatives, in this case by reaction with chloroformates due to advantages of speed, safety and the aqueous medium in which the reaction occurs. The method proposed for the proteinaceous binding media study is to calculate the proportions of the different amino acids with respect to alanine. This method provided goo…