Influence of boron addition on the phase transformation, microstructure, mechanical and in-vitro cellular properties of bredigite-type coatings deposited by a spin coating technique

• Published in: Materials chemistry and physics 2022-05, Vol.283, p.126049, Article 126049
• Main Authors: Sopcak, T., Shepa, I., Csanádi, T., Medvecky, L., Giretova, M., Kucharova, V., Sedlak, R., Balazsi, K., Stulajterova, R., Streckova, M.
• Format: Article
• Language: English
• Subjects: Atomic force microscopes; Atomic force microscopy; Biocompatibility; Biomedical materials; Boron; Bredigite; Calcium phosphates; Calcium silicates; Cell response; Cellular structure; Coatings; Differential thermal analysis; Grain boundaries; Infrared analysis; Ion beams; Mechanical properties; Microstructure; Modulus of elasticity; Nanohardness; Nanoindentation; Nanoparticles; Orthopedics; Polyvinyl alcohol; Silicates; Sol-gel processes; Spin-coating; Structural analysis; Substrates; Titanium
• ISSN: 0254-0584; 1879-3312
• DOI: 10.1016/j.matchemphys.2022.126049

Doped calcium silicates, e.g. bredigite (Ca7MgSi4O16) have recently become a growing interest in biomedicine thanks to outstanding biocompatibility, bioactivity, and improved mechanical properties when compared to calcium phosphate counterparts. Here, we have produced thin bredigite-type coatings on Ti6Al4V substrate by the polyvinyl alcohol (PVA) assisted sol-gel spin-coating technique and studied the influence of boron incorporation (0.5 and 1.0 mol) on the microstructural, phase, nanomechanical, and in-vitro cellular properties of deposited coatings. Chemical and structural analysis of the coatings was thoroughly performed by Focussed Ion Beam Scanning Electron Microscope (SEM/FIB), Atomic Force Microscopy (AFM), differential thermal analysis (DTA-TG), X-ray diffraction (XRD), and Fourier-Transform Infrared spectroscopy (FTIR), while the nanomechanical properties were evaluated by nanoindentation and nanoscratch tests. Overall, all deposited films were smooth and porous composed of ∼25–50 nm nanoparticles. The boron incorporation increased the coating thickness as a result of PVA interaction with borate ions. The nanomechanical properties (Young's modulus, nanohardness, critical load for cracking) decreased by the boron addition as a result of decreasing the strength of grain boundaries between the nanoparticles. The in-vitro contact cytotoxicity testing revealed high proliferation of the osteoblast cells in all coatings giving the potential of application in orthopedics. •Bredigite coatings were deposited on Ti6Al4V by PVA assisted sol-gel spin-coating.•Deposited coatings were smooth and porous composed of ∼25–50 nm nanoparticles.•Boron incorporation affect the physico-chemical and mechanical properties of coatings.•Nanomechanical properties of coatings decreased by the boron addition.•All deposited coatings revealed high proliferation of osteoblastic cells.