Promoting osteoblast proliferation and differentiation on functionalized and laser treated titanium substrate using hydroxyapatite/β-tricalcium phosphate/silver nanoparticles

Abstract

In the present study, a novel composite coating consisting of nano-silver (nAg) with an association of hydroxyapatite (HA)- β-tricalcium phosphate (β-TCP) particles was developed by surface coating onto Ti substrate through two different but aligned steps: first nAg-HP (containing a different ratio of HA and β-TCP particles) composite was coated by sol-gel technique with the association of poly (vinyl alcohol) (PVA) as a binding agent to the substrate, then continuous CO2 laser treatment was carried out to improve the surface properties. The physicochemical properties of fabricated coatings were evaluated by using X-ray diffractometry (XRD), and field emission scanning electron microscopy (FESEM) equipped with energy dispersive X-ray detector (EDX). The biological properties of composite coatings were observed by bioactivity measurement, antibacterial performance, MTT assay, and real-time PCR. The FESEM images and cross-section micrographs showed that the particles were distributed homogenously, and the interface was well-integrated. Mineralization assessment revealed treated surface was a better place for apatite nucleation and growth. The antibacterial measurement showed Ag nanoparticles enhanced significantly antibacterial activity reached up about 90%. The mRNA expression level for COL1A1, ALP, RUNX2, OCT, and GAPDH revealed the positive effect of functionalized and treated Ti substrate on osteoblast cell differentiation. The composite coating illustrated enhanced biological properties suggesting it is a promising candidate for further studies for practical biomedical applications.