Biologically Modified Titanium Substrates for Improved Surface Bioactivity

Document Type: Original Article

Authors

Stem cell and regenerative medicine group, National Institute of Genetic Engineering and Biotechnology, Tehran, Iran

Abstract

Post-surgery infections and not effective integration represent a serious issue in the Titanium  (Ti)  based  implants  function  for  a  long  term  stability.  To reduce such issue various surface functionalization method including surface coating has been explored.  Here,  we  successfully  coated  Ti  substrates  with  Graphene  Oxide  (GO), Chitosan (Cs), and nanocomposite of GO and Cs (GO/Cs) via spin coated method to evaluate the osteogenic properties of each coatings. Uncoated Ti substrates were used as control. Scanning electron microscopy was used to investigate the coating morphology. Surface roughness measurements were achieved from atomic force microscopy. To measure surface wettability, contact angels method was performed. Ti substrates coated with Cs (TiCs) and Cs/GO (TiCs/GO) showed the highest surface wettability compared to Ti substrates coated with GO (TiGO) and the control. The highest surface roughness was also observed in TiCs/GO. To test cellular attachment and proliferation the samples were exposed to human osteoblast-like MG63 cells after 2 hours, 4 hours, 6 hours, 1 day, 3 days, and 1 week. MTT [3-4,5 dimethylthiazol-2yl (2,5diphenyl-2H-tetrazoliumbromide)] assay was performed to measure the percentage of cellular attachment and proliferation for each coatings. Cell adhesion and cell proliferation was most improved in TiCs followed by TiCs/GO. Corrosion resistance of the coatings was investigated using potentiodynamic polarization test in simulated body fluid. The result indicated that the nanocomposite coating could provide effective protection of Ti substrates from corrosion.

Keywords