Analytical Approaches Based on Gas Chromatography Mass Spectrometry (GC/MS) to Study Organic Materials in Artworks and Archaeological Objects

Abstract

Gas chromatography/mass spectrometry (GC/MS), after appropriate wet chemical sample pre-treatments or pyrolysis, is one of the most commonly adopted analytical techniques in the study of organic materials from cultural heritage objects. Organic materials in archaeological contexts, in classical art objects, or in modern and contemporary works of art may be the same or belong to the same classes, but can also vary considerably, often presenting different ageing pathways and chemical environments. This paper provides an overview of the literature published in the last 10 years on the research based on the use of GC/MS for the analysis of organic materials in artworks and archaeological objects. The latest progresses in advancing analytical approaches, characterising materials and understanding their degradation, and developing methods for monitoring their stability are discussed. Case studies from the literature are presented to examine how the choice of the working conditions and the analytical approaches is driven by the analytical and technical question to be answered, as well as the nature of the object from which the samples are collected.

Characterization of the residues in Han Dynasty bronze lamps by pyrolysis–gas chromatography–mass spectrometry

“…The hydrocarbons present including linear alkanes (ranging from C21 to C35, with the most abundant being C27) with carbon atoms of both odd and even numbers, and the alkanes with carbons of odd numbers were more abundant than with even-numbered, and minor amounts of alkenes are present. The main chromatographic features of raw beeswax are in accordance with the literature [16,19,21]. Moreover, according to the research about fingerprints of beeswax from 10 provinces in China, the components vary slightly on relative amount as their fingerprint characteristics [27], meaning that although the beeswax samples have different origins, the main features are same.…”

“…The main techniques used to characterize organic remains from cultural heritage sites are Fourier transform infrared (FT-IR) spectrometry [12], high-performance liquid chromatography-mass spectrometry (LC/MS) [9], gas chromatography coupled to mass spectrometry (GC/ MS) [13][14][15][16][17], high-temperature gas chromatography coupled to mass spectrometry (HT-GS) [18] and pyrolysis-gas chromatography-mass spectrometry (Py-GC/ MS) [19][20][21][22]. Py-GC/MS with thermally-assisted hydrolysis and methylation (THM) has the advantages of offering high sensitivity and requiring a facile pretreatment of the samples [23], and this method has been successfully used to characterize the remains in Tang Dynasty lamps [20].…”

Shedding light on the colours of medieval alabaster sculptures: Scientific analysis and digital reconstruction of their original polychromy

“…To identify precisely organic colourants, the molecular detailed information provided by hgh‐performance liquid chromatography‐MS can be exploited if microsamples (50‐100 μg) can be taken . Similarly, the binding media and gilding mordants can be identified more precisely using pyrolysis gas chromatography mass spectrometry (Py‐GC‐MS) on microsamples of the same size …”

“…16,17 Similarly, the binding media and gilding mordants can be identified more precisely using pyrolysis gas chromatography mass spectrometry (Py-GC-MS) on microsamples of the same size. 18 Other complementary techniques were used, such as technical photography (TP) and fiber optic reflectance spectroscopy (FORS), which can be used noninvasively to highlight the presence of certain pigments and colourants. [19][20][21][22] An initial survey with FORS was useful to plan the sampling and analyses, and TP allows the more extensive investigation and comparison of areas on the objects, which bore similarity to areas where the presence of specific materials had been identified by analyses, thus minimizing the number of samples needed.…”

Was Lacquer the Key Ingredient for Luxurious Jinyin Pingtuo Products in the Tang Dynasty of China (AD 618–907)?

“…However, the relative low abundance of dicarboxylic and hydroxycarboxylic acids was not consistent with the presence of a siccative oil (Bonaduce et al . ). In addition, two molecular markers (hexadecanenitrile and octadecanenitrile) were detected, and these are indicative of the presence of egg yolk (Bonaduce and Andreotti ).…”