Derivatization Method for the Determination of Amino Acids in Tobacco by Gas Chromatography-mass Spectrometry

In this paper, we evaluated the use of a silylation reagent N-methyl-N-(tert-butyldimethylsilyl)trifluoroacetamide in the microwave-assisted derivatization method to replace a traditional prolonged heating method for the determination of 12 amino acids. Several parameters, including the kind of extraction solvent, extraction time, microwave power and microwave time, were optimized. The experiment showed that the optimal derivatization time was 3 min with a microwave power of 240 W. The calibration curves were linear with the correlation coefficients ranging from 0.995 to 1.000 in the concentration levels between 0.1-20 mu g/mL and the relative standard deviations were between 4.4 and 18%. The limits of detection were 0.1-2.4 mu g/mL and the recoveries of those compounds were 62-115%. A comparison of this method to other methods has demonstrated that the proposed method is a rapid and reliable sample-treatment procedure for amino acids determination in real tobacco samples.