Matrix assisted laser desorption ionization (MALDI) is a very popular ionization process widely used for proteins and peptides characterization. The presented technology enables modification of almost any conductive material including indium-tin oxide (ITO) glass, aluminum, stainless steel or conductive polymers. The MALDI targets are functionalized by reactive landing of ions under atmospheric conditions. The MALDI plates can be modified by proteins, peptides or by inorganic compounds such titanium dioxide or zirconium dioxide. Proteins, such as enzymes, lectins or antibodies stick after the deposition on the surface very efficiently and remain active. The activity is used for "on plate" digestion or enrichment of different types of antigens or compounds.