Natural complex mixtures such as oil and dissolved organic matter play an important role in the economy and in the global carbon cycle. One of the most promising approaches for the investigation of the chemical structure of such substances is the combination of the high-resolution mass spectrometry and selective chemical reactions. Here, we report the investigation of the ozonation products of natural complex mixtures using Fourier transform ion cyclotron resonance mass spectrometry. Ozonation of crude oil results in the appearance of the new compounds with high content (up to 9 atom) of oxygen. Isotopic exchange reaction showed that those oxygen stem from the carbonyl groups. Ozonation of the dissolved organic matter leads to the destruction of the substance and shift towards the region of the saturated compounds.
Keywords: Fourier transform ion cyclotron resonance; Oil; crude oil; dissolved organic matter; electrospray ionization; humic acids; ozone.