PETROLEUM SCIENCE AND TECHNOLOGY

Transition metal oxide nanoparticles as surfaces for surface-assisted laser desorption/ionization mass spectrometry of asphaltenes
Olaitan AD, Reyes KA, Barnes LF, Yount JR, Ward S, Hamilton HSC, King KE, Van Leeuwen CJ, Stepherson JR, Vargas TK, Kirkconnell MP and Molek KS
We report the first use of NiO, FeO, TiO, and CoO nanoparticles as surfaces for surface-assisted laser desorption/ionization (SALDI) mass spectrometry of asphaltenes. Higher ratios (S/Ns) for asphaltene species were observed using NiO and FeO nanoparticles for SALDI as compared to LDI, where both surfaces consistently provided 2- to 3-fold improved S/Ns. The new SALDI detection method showed reliable adsorption data measuring supernatant solutions after 24 hour asphaltene adsorption on NiO, FeO, and CoO. These results indicated that NiO has a higher adsorption affinity than FeO and CoO for asphaltene molecules, corroborating reported asphaltene adsorption on metal oxide nanoparticles.