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Asphaltenes analysis still remains a challenge due to their unknown molecular structure and self-associative behavior. FT-ICR MS analyses using five different ionization methods, ESI, APCI, APPI, LDI and MALDI, in both positive and negative mode were performed. A characteristic and typical behavior was observed for the experiments using LDI(±) and MALDI(±)FT-ICR analyses: a broadband mass spectrum ranging from m/z 500 to 3000 was observed with a 24 Da interval. This phenomenon was attributed to fullerene cluster formation. The most abundant allotropic form of fullerene, C₆₀, was observed at m/z 719.99914. These species were not observed in APCI(+)/APPI(+) analyses. This last analysis of asphaltene samples doped with the C₆₀ solution promptly reveals the typical fullerene ions. LDI(+) analyses of pure C₆₀ showed condensation products. These results indicate a clusterization of asphaltenes in …