α,ω-N,N-Dimethylaminoalkylamines as Possible Derivatization Agents for the Analysis of Small Carbonyl Compounds by Low Energy Mass Spectrometry

Reaction with α,ω- N,N-dimethylaminoalkylamines (2-dimethylaminoethylamine, 3-dimethylaminopropylamine, 4-dimethylamino-butylamine) to form Schiff bases followed by quaternization of the N,N-dimethylamino group by alkyl (deuteroalkyl) halides to generate fixed-charge fragments is suggested for the characterization of carbonyl compounds by matrix-assisted laser desorption ionization (MALDI) mass spectrometry. As model objects, some aliphatic aldehydes and alicyclic and steroid ketones were involved in the modification. Using gas chromatography-mass spectrometry, the first modification stage proved to be quantitative. Not only the MALDI conditions but also the nanostructurized target provided spectra that revealed peaks for the cationic parts of derivatives. It was shown that the use of deuterated alkyl halides allows one to prepare deuterium-labeled standards for possible quantitative analysis.