Cytotoxic and Bacteriostatic Activity of Nanostructured TiO₂ Coatings

Abstract

A b s t r a c t Nanostructures are structures, mainly synthetic (nanosurfaces, cylindrical nanotubes, and nanospheres), which range between 1-100 nm in at least one dimension and can be engineered to a wide range of physical properties. This paper aims to explore the bacteriostatic and cytotoxic characteristics of nano-TiO 2 coated specimens of glass, stainless steel and ceramic with different thickness and roughness. The results show that stainless steel and glass specimens with a nano-TiO 2 coating thickness of 200 nm have a bacteriostatic effect of 97% and 100%, respectively after 30 minutes of UV exposure. Glass specimens with a nano-TiO 2 coating thickness of 750, 200 and 50 nm have a bacteriostatic effect of 86%, 93% and 100% after 60 minutes. Nano-TiO 2 coatings show a great bacteriostatic but not a cytotoxic effect, thus representing a valuable alternative for biomedical applications.K e y w o r d s: bacteriostatic effect, cytotoxic activity, TiO 2 coatings

Antibacterial Effect of Aluminum Surfaces Untreated and Treated with a Special Anodizing Based on Titanium Oxide Approved for Food Contact

“…Such effect became significant once applied all sanitizing agents, thus supposing a synergistic activity characterized by a photocatalytic reaction of both oxides (aluminum and titanium) under UV radiation, as was also demonstrated by different literature reports [66][67][68][69]. The similar bactericidal effects observed after alcohol treatment might be ascribed to a synergistic effect of the friction with the sterile spatula and titanium oxide [66,70] within the DURALTI ® coating. In fact, the 6 logarithms reduction observed in our study was in agreement with that observed by Graziano et al [71].…”

A Time-Course Study on a Food Contact Material (FCM)-Certified Coating Based on Titanium Oxide Deposited onto Aluminum

“…It is therefore fundamental to find reliable solutions to prevent such an untoward release and, at the same time, exert a rapid bacteriostatic and/or bactericidal effect. In this regard, nanotechnological coatings have shown great potential in terms of biocompatibility and leaching prevention [ 19 , 20 , 21 , 35 ].…”

“…To date, nanocomposites (nanoparticles, clay and silicate nanoplatelets, carbon nanotubes, starch nanocrystals and cellulose-based nanofibers) are the most used materials in the food industry, for packaging and coating purposes [ 25 , 26 , 27 , 28 ]. Owing to their intrinsic photocatalytic activity or the release of metallic ions, silver [ 29 , 30 , 31 ], golden [ 32 , 33 , 34 ] and metal oxide (TiO 2 , ZnO, Fe 3 O 4 , CuO, MgO) [ 8 , 35 , 36 , 37 , 38 , 39 ] nanoparticles showed the most effective and reliable biocidal activity against both Gram-positive and Gram-negative bacteria via ROS generation [ 40 ]. In particular, TiO 2 , a thermally stable, biocompatible, semiconducting transition metal, endowed with good resistance to chemical erosion and a wide bandgap of 3.2 eV, has also been extensively used for other purposes, including deodorant and self-cleaning [ 41 , 42 , 43 , 44 ].…”

Antibacterial Effect of Stainless Steel Surfaces Treated with a Nanotechnological Coating Approved for Food Contact

“…In the last decade, the deposition of nanotechnological coatings by cathodic arc physical vapor deposition (PVD) [ 22 ], cyclonic atmospheric pressure plasma [ 23 ], metal injection molding [ 24 ], sol-gel process, dip-coating technique [ 25 ], and plasma-enhanced chemical vapor deposition (PECVD) [ 26 ] gained great importance due to their ability to control metal ions release and enhance hydrophobicity and cleanability. At the same time, the need for new sanitizing treatments able to reduce/inhibit bacterial retention, prevent stainless steel equipment degradation and, in turn, reduce/eliminate food contamination and chemical elements release is also of great relevance [ 3 , 27 ].…”