A method of surface modification for analyzing of phosphorylated peptides. The surface of solid substrates is modified for efficient phosphorylated peptide preconcentration from complex peptide mixtures prior to detection based on desorption/ionization mass spectrometry. The method of surface functionalization is introduced by ambient ion landing. The approach is based on electronebulization, differently said electrospray, of solutions of organometallic compounds related to elements of 4B class of periodic table of elements, especially to zirconium, hafnium and titanium. The generated charged electrospray is dried on the fly by passing the heated compartment and focused to a surface for modification forming a stable oxide layer there. The surface modified this way has been used for phosphopeptide enrichment from peptide mixtures prior to desorption/ionization mass spectrometry.