PYROLYSIS METHYLATION - A MICROANALYTICAL METHOD FOR INVESTIGATING POLAR ORGANIC-COMPOUNDS IN CULTURAL PROPERTIES/

The organic compounds present in weathered surfaces of building stones were investigated using simultaneous pyrolysis/methylation. The metho d consists of the derivatization of the sample with the alkylating rea gent tetramethylammonium hydroxide. Tetramethylammonium salts of organ ic acids can be converted to methyl ester and the corresponding byprod uct in the pyrolysis unit. Hydroxyl groups are also methoxylated. The protection of functional groups permits direct and complete analysis o f samples by pyrolysis. No time-consuming solvent extractions, concent rations, derivatizations, and other manipulations which imply the poss ibility of cross-contamination, are required. The data obtained by sol vent extraction and subsequent gas chromatography-mass spectrometry an alysis are similar to those obtained by pyrolysis/methylation, proving that this method is an analytical procedure of great sensitivity for investigating organic compounds in inorganic matrices.