Synthesis of NanoscaleTiO2and Study of the Effect of Their Crystal Structure on Single Cell Response

To study the effect of nanoscale titanium dioxide (TiO 2 ) on cell responses, we synthesized four modifications of the TiO 2 (amorphous, anatase, brookite, and rutile) capable of keeping their physicochemical characteristics in a cell culture medium. The modifications of nanoscale TiO 2 were obtained by hydrolysis of TiCl 4 and Ti(i-OC 3 H 7 ) 4 (TIP) upon variation of the synthesis conditions; their textural, morphological, structural, and dispersion characteristics were examined by a set of physicochemical methods: XRD, BET, SAXS, DLS, AFM, SEM, and HR-TEM. The effect of synthesis conditions (nature of precursor, pH, temperature, and addition of a complexing agent) on the structural-dispersion properties of TiO 2 nanoparticles was studied. The hydrolysis methods providing the preparation of amorphous, anatase, brookite, and rutile modifications of TiO 2 nanoparticles 3–5 nm in size were selected. Examination of different forms of TiO 2 nanoparticles interaction with MDCK cells by transmission electron microscopy of ultrathin sections revealed different cell responses after treatment with different crystalline modifications and amorphous form of TiO 2 . The obtained results allowed us to conclude that direct contact of the nanoparticles with cell plasma membrane is the primary and critical step of their interaction and defines a subsequent response of the cell.