Electrodeposition of Chitosan on Ti-6Al-4V Surfaces: A Study of Process Parameters

The effect of different electrodeposition variables of chitosan coatings on Ti-6Al-4V substrates is studied. Electrolytic solutions containing chitosan at 0.1, 0.5, and 1.0 wt/v% was used to coat Ti-6Al-4V grit-blasted samples through electrodeposition, at 1.5 and 3.0 V, for 2.5, 20 and 30 min. Coating surface morphology was analyzed by scanning electron microscopy. Adhesion behavior was characterized by scratch testing, and coating stability under physiological conditions was assessed by swelling test. Electrodeposited coatings with longer times and high chitosan concentrations produced porous coatings, with a hydrogel-like structure, with better surface adhesion than those at lower concentrations and times. Swelling tests displayed a high initial swelling with posterior rapid degradation and stabilization at 3h, indicating the potential need for a crosslinking agent. These results suggest that chitosan electrodeposition has great potential for coating applications of metallic implants, and further in vitro cell assays are proposed for future studies.

Keywords:
Bioactive coatings; metallic implants; electrochemical deposition; chitosan; hydrogel