Characterization of Chitosan Polyethylene glycol Hydroxyapatite composite coatings fabricated by dip coating

Abstract

The development and characterization of bioactive surfaces based on chitosan-polyethylene glycol coatings modified with hydroxyapatite on Ti6Al4V alloy were conducted to enhance bioactivity. Characterization techniques such as scanning electron microscopy, X-ray diffraction, infrared spectroscopy, atomic absorption spectroscopy, and electrochemical impedance spectroscopy were used to evaluate coating properties, apatite formation after immersion in simulated body fluid, and electrochemical stability. Results demonstrated apatite deposition due to the bioactivity of the polymer-ceramic composite, with calcium accumulation observed on the substrate surface after 5 days of immersion. Electrochemical impedance spectroscopy revealed a highly capacitive layer in the 50:50 chitosan-polyethylene glycol coating with 0.05% w/v hydroxyapatite, indicating increased interaction with the biological medium while preserving the protective resistive properties of the Ti6Al4V alloy. These findings suggest that this coating composition is a promising material for bone tissue regeneration applications.

Keywords

• Ti6Al4V alloy
• surface modification
• alkaline treatment
• polymer-ceramic coatings
• bioactive coatings
• simulated body fluid