title: Layer-by-Layer assembly of TiO2 nanoparticles for stable hydrophilic biocompatible coatings.
abstract: Stable, super-hydrophilic (water contact angle approximately equal to 0 degrees) titanium dioxide nanoparticle thin films have been obtained on substrates with different initial wettability such as glass, poly(methyl methacrylate) and poly(dimethyl siloxane) using layer-by-layer nano-assembly method. Titanium dioxide nanoparticles were alternated with poly(styrene sulfonate) to form films of thickness ranging from 11 nm to 220 nm. The hydrophilicity of these thin films increases with increasing number of deposited PSS/TiO2 bilayers. It was found that 2, 5 and 20 layers were needed to form super-hydrophilic TiO2 coating on glass, PMMA and PDMS respectively. Oxygen plasma treatment of substrate surfaces enhanced the formation of homogeneous TiO2 films and accelerated the formation of hydrophilic layers. Super-hydrophilicity has been shown to be unique to PSS/TiO2 films as compared with other polyelectrolyte/nanoparticle layers, and UV irradiation may restore hydrophilicity even after months of storing of the samples. Biocompatibility of TiO2 nanoparticle films has been demonstrated by the successful cell culture of human dermal fibroblast.
authors.affiliation: Institute for Micromanufacturing, Louisiana Tech University, Ruston, LA 71272, USA.
authors.forename: Dinesh S
authors.initials: DS
authors.lastname: Kommireddy
authors.forename: Amish A
authors.initials: AA
authors.lastname: Patel
authors.forename: Tatsiana G
authors.initials: TG
authors.lastname: Shutava
authors.forename: David K
authors.initials: DK
authors.lastname: Mills
authors.forename: Yuri M
authors.initials: YM
authors.lastname: Lvov
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry*; D018929:Cell Culture Techniques / Q000379:methods*; D049109:Cell Proliferation; D002478:Cells, Cultured; D020099:Coated Materials, Biocompatible; D004129:Dimethylpolysiloxanes / Q000032:analysis; D005347:Fibroblasts / Q000166:cytology*; D046210:Microfluidic Analytical Techniques; D008855:Microscopy, Electron, Scanning; D036103:Nanotechnology; D019904:Polymethyl Methacrylate / Q000032:analysis; D011137:Polystyrenes / Q000737:chemistry; D013499:Surface Properties; D014025:Titanium / Q000032:analysis / Q000737:chemistry*; D014466:Ultraviolet Rays
chemical_list: D001672:Biocompatible Materials; D020099:Coated Materials, Biocompatible; D004129:Dimethylpolysiloxanes; D011137:Polystyrenes; C009495:titanium dioxide; C003321:polystyrene sulfonic acid; D019904:Polymethyl Methacrylate; D014025:Titanium