Recent developments in hydroxyapatite coating on magnesium alloys for clinical applications

Mg alloys have been attracted as potential biomaterials for clinical application as implant materials because of their exclusive properties including biodegradability, bioactivity, oseointegration etc. Despite these, their fast degradation and a comparatively higher rate of corrosion in the biological environment hide their potential use in biomedical applications. However, hydroxyapatite (HA) is a naturally occurring mineral that can offer desired properties like bioactivity, biocompatibility, high osteoconductivity, non-inflammatory, and non-toxicity. Numerous approaches have been adopted to fabricate the HA coatings on Mg alloys to overcome the chal-lenges but still some concerns are there.This article mainly focuses on the development of various methodologies including the electro-deposition process, sol-gel, micro-arc oxidation process, etc., to minimize the overall challenges for the preparation of HA coating layers on the surfaces of Mg alloys for biomedical applications. In addition, the physical properties, mechanical integrity, corrosion properties, and biomedical properties have been discussed.