Laser desorption ionization and collision induced dissociastion as powerful tools for FT-ICR mass spectrometric characterization of asphaltene fractions enriched in island and archipelago motifs

Abstract

Due to advances in mass spectrometry, it is widely accepted that asphaltenes molecules from the island and archipelago motifs coexist in the samples. However, analyzing asphaltenes remains a challenging task mostly due to these species' high complexity and self-association tendencies. Herein we introduce laser laser desorption ionization (LDI) as an adequate tool to ionize even the most unstable samples. In addition, we demonstrate collision-induced dissociation (CID) experiments as a powerful tool to perform structural characterization of asphaltenes. Using these tools, it was possible to characterize asphaltene samples enriched in island and archipelago-type structures in a much easier way without any capillary obstructions and damages to the equipment. Also, it was possible to perform an in-depth analysis of asphaltene and propose structures to asphaltene detected in the most abundance in the selected samples. Finally, the relative percentages of product ions derived from the cleavage of alkyl bridges between aromatic nuclei in archipelago-type molecules were calculated, and we tried to establish correlations with the asphaltene structures with their stability.