Khabibullin Vladislav Rafaelevich RussiaSaratovSSU. Institute of Chemistry., 410012, Saratov, Astrakhanskaya str., 83, building. 1, Institute of Chemistry, SSUvladhab1995@gmail.ru Author's articles Sorption-fluorimetric Determination of Enrofloxacin with Magnetite Nanoparticles Modified by Polyethylenimine Preconcentration of Е110 and Е124 Food Azodyes on Magnetite Nanoparticles Modified by CTAB