Reshetnikova Irina Sergeevna RussiaSaratovSSU. Institute of Chemistry., 410012, Saratov, Astrakhanskaya str., 83, building. 1, Institute of Chemistry, SSUirkasar@ya.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 Spectrophotometric Study of the Stability the Quercetin and Rutin Solutions at Different Acidity of the Medium Chromatographical Analysis of Meldonium with Preliminary Concentration by Solid-Phase Extraction on Magnetite Nanoparticles