Investigation of Biodegradable Composite Coated Magnesium Alloy Using Optical Coherence Tomography

Abstract

Optical coherence tomography (OCT) was used to characterize poly (lactic-co-glycolic acid) (PLGA) and nanophase hydroxyapatite (nHA) / PLGA coatings on magnesium (Mg) substrates before and after immersion in revised simulated body fluid (rSBF) under standard cell culture conditions. The OCT images clearly showed: the surface of the coatings, the metallic surface underneath the coatings, the presence of a dispersed phase within the polymer matrix, and defects and structural changes to the coatings. This study demonstrated the potential utility of OCT for performing quality assurance tests and for tracking the physical effects of degradation upon biomedical implants due to its ability to rapidly render easily interpreted images of sub-surface structure in a non-destructive manner.