Pulsed laser deposited bioactive RKKP-Mn glass-ceramic coatings on titanium

The study is aimed at the design of materials, i.e. glass-ceramics, containing trace elements with a specific role in the biological process of regenerating osteoporotic bones. Among these, manganese has a key function in bone osteogenesis and in the maintenance of bone mass. In this work, a 2 wt% of manganese containing RKKP glass-ceramic material has been prepared by sol-gel synthesis. Pulsed laser deposition technique has been applied to deposit films on titanium from the prepared glass-ceramic target. The films have been deposited at two different substrate temperatures (room (RT) and 500 °C) and investigated by X-ray diffraction, Raman spectroscopy, and SEM-EDX techniques. Both the films are characterized by a compact, crack-free and rough surface. The films deposited at 500 °C are composed of crystalline wollastonite and hydroxyapatite phases. For the assessment of films bioactivity in vitro, the standard Kokubo protocol for simulated body fluid (SBF) preparation has been followed. The films deposited at RT and 500 °C have been soaked in SBF for 3, 7, 14 and 28 days. For the film deposited at RT, apatite phase is registered after 7 days of soaking, whereas for the film deposited at 500 °C the apatite appeared only after 14 days. Moreover, the film deposited at RT induces a faster crystallization of the apatite layer.