A novel method for the preparation of crude oil samples based on a xerogel matrix was developed for elemental analysis using laser ablation–double focusing sector field inductively coupled plasma-mass spectrometry. The samples and aqueous solution were successfully encapsulated using zirconium n-propoxide. The use of xerogel produces stable and homogeneous pellets, avoids splashing of the sample and allows the use of aqueous inorganic standards to elaborate the calibration curve. Sulfur, nickel and vanadium were selected as test elements and indium was used as the internal standard to correct the variations in the amount of material ablated. The correlation coefficients of the calibration curves for all the elements tested were better than 0.990 except for sulfur. Crude oil results showed no significant statistical differences between the sol–gel results and those obtained with similar studies.Escuela de Qu ımica, Facultad de Ciencias, Universidad Central de Venezuela, P.O. box 47102, Caracas 1041a, Venezuela. E-mail: jose. chirinos@ciens.ucv.ve; Fax: +58 212 6934977; Tel: +58 212 6051174 CNRS-UPPA, UMR 5254, LCABIE, H elioparc, 2av. Pr. Angot, 64053 Pau, France