Fabrication and Characterization of Chitosan-Based Bioactive Coatings on Titanium or Its Alloys

Currently, titanium and its alloys do not entirely meet the comprehensive criteria for implants, which include effective integration with surrounding tissues, heightened corrosion resistance in human bodily fluids, and antimicrobial activity. Consequently, extensive research endeavors are in progress to modify the surfaces of these materials to attain the desired properties. One avenue being explored involves the deposition of coatings using diverse methods. Common materials employed for implant coatings encompass bioceramics, biopolymers, and metals, often in nanoparticulate form, or their combination to create composites. Biopolymers of natural origin, particularly notable for their high biocompatibility, bioactivity, and antibacterial attributes, are gaining attention. In this context, chitosan, derived from chitin found in the exoskeletons of crustaceans, insects, and the cell walls of fungi, emerges as a standout candidate. Chitosan-based coatings, fabricated by various techniques on metallic surfaces, are gaining increasing attention in implantology due to their effects on bone tissue integration processes, accelerated wound healing, and the ability for controlled drug delivery. However, the challenge is to achieve these outcomes simultaneously. Developing a homogeneous coating that fully surrounds the often-developed implant surface to provide robust resistance to the corrosive environment of the human body is proving to be a difficult task. Moreover, ensuring strong adhesion of such coatings to the implant and their resistance to wear is an additional challenge. This chapter will describe the properties of chitosan that promote its use as an implant coating material and discuss various combinations of chitosan-based bioactive coatings deposited using techniques such as solution casting, dip coating, spin coating, layer-by-layer, and electrospinning on the surface of titanium or its alloys.