Three different approaches to preconcentration of metal ions using low-polar sorbents were compared: dynamic coating of the sorbent surface with hydrophobic chelating reagent; impregnation of the sorbent with a solution of the reagent in a suitable volatile organic solvent; and on-line merging of sample and reagent streams prior to solid-phase extraction of metal-reagent complexes. Lanthanum was used as a model analyte; 1-phenyl-3-methyl-4-benzoylpyrazol-5-one (PMBP) as a reagent for preconcentration. It was found out that the most effective approach for the analyte recovery from a large sample volume is the use of a dynamically coated sorbent with high specific surface.