Combination of graphite-assisted laser desorption/ionization (GALDI) mass spectrometry and thin layer chromatography
T11N2
R.S. Borisov, N.Yu. Polovkov, D.I. Zhilyaev, C.A. Esparza, V.G. Zaikin
A.V. Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences,
The potential of using the graphite matrix for laser desorption/ionization from thin-layer chromatography (TLC) spot has been studied. Using a series of pharmaceutical substances with various functional groups and synthetic N-heterocyclic compounds, it has been shown that simple applying a graphite to TLC spots (tracing the contour spots and shading spots with pencil lead) provided an efficient desorp tion/ionization of analytes. In the main cases, the recorded mass spectra revealed only the [M+Na]+ и [M+K]+ ion peaks whose doublets can be used for the determination of molecular masses. Appearance of the [M+H]+ ion peaks in some mass spectra may be the results of the presence of mineral acids in the samples. The described approach to melt application of the «matrix» to analyte spots eliminates the danger of spots erosion by solution or organic matrix, simplifies the procedure and shortens the time required for sample preparation.