Лазерная десорбционная масс-спектрометрия акридиновых красителей, адсорбированных на поверхности пленок ТiO2 и SiO2

The systems containing acridine yellow and. acridine orange dyes adsorbed pn the surface of mesoporous TiO2 and SiO2 films have been studied by laser desorption/ionization (LDI) tnass-spectrometry. The set of ions which formation is caused by specific interaction of dyes with nanostructured dioxides under LDI conditions was identified on the basis of comparison with mass spectra of polycrystalline dyes on metallic surface and dissolved in liquid matrix. It has been shown that preferred desorption of cationic form of dyes [M+H]+ occurs under LDI from the films with a monomeric form of dye adsorption. Dye adsorption in dimeric and clustered forms reverberates is reflected in appearance in the LDI mass spectra of dimeric doubly charged ions [2M+3J2+ as well as products of thermoionization and redox process M+, [M-H]+, and [M+2H]+, which are stimulated in dye aggregates by laser irradiation over the UV-range. Photoelectronic properties of TiO2 films promote more active behavior of light etching processes in adsorbed dyes in comparison with the SiO2 ones.