Study of methylation and ethylation by thermochemolysis of tuberculostearic acid from Mycobacterium tuberculosis culture and sputum

The direct analysis of TBSA was performed by thermally assisted hydrolysis and alkylation in M.tb culture dilutions and in sputum deposits, using tetramethyl ammonium hydroxide (TMAH) and tetraethylammonium hydroxide (TEAH) as derivatizing agents. Thermochemolysis of fatty acids was done in a programmable temperature PTV inlet Optic3, combined with an automatic LINEX liner exchanger installed on an Agilent GC-MS system. The GC-MS response is discussed and the results are compared for the two alkylating reagents used.