NIR-Reflective and Hydrophobic Bio-Inspired Nano-Holed Configurations on Titanium Alloy

PISTONESI, MARCELO FABIÁN; PRADO, FERNANDO DANIEL; GRAVINA, A. NOEL; GARCÍA, NICOLÁS A.; BELÉN, FEDERICO; RUSO, JUAN. M.; MESSINA, PAULA V.

ACS APPLIED MATERIALS & INTERFACES

AMER CHEMICAL SOC

Lugar: Washington; Año: 2022 vol. 14 p. 5843 - 5855

1944-8244

Near infrared radiation (NIR) plays an important role in guided external stimulus therapies; its application in bone-related treatments is becoming more and more frequent. Therefore, metallic biomaterials that exhibit skills activated by NIR become a promise for further orthopaedic procedures. In this work, we present an adapted electrodepositing approach to attain a biomorphic nano-holed TiO2 coating on Ti6Al4V alloy. Throughout of a precise control of the anodization conditions, structures revealed the formation of localized nano-pores arranged in a periodic assembly. This specific organization provoked a higher stability against thermal oxidation and precise hydrophobic wettability behaviour according to Cassie?Baxter?s model; both characteristics that are a prerequisite to ensure a favourable biological response in an implantable structure. In addition, the periodically arranged sub-wavelength-sized unit cell on the metallic-dielectric structure exhibits a peculiar optical response which results in higher NIR reflectivity. Accordingly, we have proved that this effect enhances the efficiency of the scattering processes and provokes a significant improvement of light confinement producing a spontaneous NIR fluorescence emission. The combination of the already favourable mechanical and biocompatibility properties of Ti6Al4V, along with a suitable thermal stability, wetting and electro-optical behaviour opens a promising path towards strategic bone therapeutic procedures.