Biomedical applications of polymer-coated hydroxyapatite materials

The primary objective of this article is to present the potential biomedical applications of hydroxyapatite-based materials coated with polymers, as well as the methods used for producing such polymer coatings. Hydroxyapatite (HA) is an inorganic component of bone, distinguished by its high biocompatibility, bioactivity, and ability to integrate with bone tissue. However, its limited mechanical strength poses a barrier to broader clinical application. A solution to this issue involves coating HA with polymeric layers—both synthetic and natural—which enhances its physicochemical properties, increases resistance to compression and fracture, and enables surface functionalization. The article outlines various coating techniques, categorized into physical and chemical methods. It also discusses examples of applications for these materials, including controlled drug delivery systems, bone tissue engineering, and gene delivery. Owing to its surface modification capabilities and favorable properties, polymer-coated HA may serve as a basis for advanced implants and drug carriers. Furthermore, the article highlights the use of HA-polymer composites for coating metallic implants, which significantly improves their corrosion resistance and enhances bioactivity. The entire study is based on a review of scientific literature that identifies current trends and research directions in the development of modern HA-based biomaterials.