The analysis of European lacquer: optimization of thermochemolysis temperature of natural resins

The search for organic compounds with TMAH thermochemolysis: From Earth analyses to space exploration experiments

“…The optimal temperature varies with the sample and the compounds that need to be derivatized. Decq [63] analyzed European lacquer and optimized the thermochemolysis temperature (350, 480, 550, 650 C) of natural resins, including Sandarac, Mastic, Colophony, Manila copla, and Congo copal. Results showed that 350 C is the optimal thermochemolysis temperature for natural resins and that 550 C is the second most optimal temperature.…”

“…In order to prepare future thermochemolysis experiments on Mars, authors studied the thermal degradation byproducts of Tenax® in the presence of the derivatization reagent MTBSTFA/ DMF and calcium perchlorate under SAM-like experimental conditions [270]. TMAH thermochemolysis experiments were also performed using chemical standards of seven kinds of nucleobases, important components of DNA and RNA, based on experimental conditions of the MOMA instrument [63]. In this study, properties of the TMAH thermochemolysis method were characterized and optimized for the detection of nucleobases under MOMA and SAMlike experimental conditions, as shown in Fig.…”

Nontargeted Pattern Recognition in the Search for Pyrolysis Gas Chromatography/Mass Spectrometry Resin Markers in Historic Lacquered Objects

“…4,6,18 Additionally, even small variations in the analysis method may influence the intensity of a peak. 19 These issues sometimes prevent conclusive identification of a lacquer's ingredients. Finding more resin markers can improve this situation.…”

“…The method used is based on earlier experiences in the analysis of varnishes and lacquers. 19 Several grains or a full lump of each sample were ground, and a small amount of 200−400 μg was transferred to a glass vial. TMAH was added (80−160 μL 2.5 wt % in methanol from 25 wt % in methanol, Sigma-Aldrich, and absolute methanol for HPLC analysis, Acros Organics, 99.99%), relative to the weight of the sample.…”

“…Aging processes influence the intensity of certain markers. − Different ingredients may interact, and markers can overlap. Many resin markers are not uniquely correlated to one resin. ,, Additionally, even small variations in the analysis method may influence the intensity of a peak . These issues sometimes prevent conclusive identification of a lacquer’s ingredients.…”