Preparation and characterization of TiO2-coated polymerization of methyl methacrylate (PMMA) for biomedical applications: In vitro study

Low surface energy and hydrophobicity of polymethyl methactylate (PMMA) are the main disadvantages of this biomaterial. The aim of this study was to investigate the effects of a new coating process on the surface characteristics and properties of PMMA. A combination of temperature and pressure was used for deposition of titanium dioxide (TiO2) on the surface of PMMA. The PMMA coated with TiO2 thin films and prepared by sputtering and noncoated PMMA were considered as control groups. The surface wettability, functional group, and roughness were determined by contact angle measurement, Fourier transform infrared spectroscopy (FTIR), and 3D laser scanning digital microscopy, respectively. The flexural strength of coated and noncoated samples was measured using three-point bending test. The cell proliferation, attachment, and viability were determined using 3-(4,5-dimethyldiazol-2-yl)-2,5-diphenyl tetrazolium bromide, live and dead assay, scanning electron microscope (SEM), and DAPI (4 ',6-diamidino-2-phenylindole) staining. The antifungal activity of TiO2 was also determined by examining the biofilm attachment of Candida albicans. The obtained results showed that TiO2 was successfully coated on PMMA. The contact angle measurement shows a significant increase of hydrophilicity in TiO2-coated PMMA. FTIR and roughness analysis revealed no loss of TiO2 from coated specimens following sonication. The cell viability after 7 days culturing on TiO2-coated specimens was more than the cell viability on the control groups. SEM images and DAPI staining showed that the total number of the cells increased after 7 days of seeding on TiO2-coated group, whereas it decreased gradually in both control groups. C. albicans attachment also decreased by 63% to 77% on the coated PMMA surface. Overall, this research suggested a new way for developing surface energy of PMMAs for biomedical applications.