Evaluation of in vitro corrosion behavior of zinc-hydroxyapatite and zinc-hydroxyapatite-iron as biodegradable composites.

Zinc (Zn) based biomaterials have been emerged as one of the capable biodegradable materials for biomedical applications because of the ideal degradation properties. In the present work, corrosion kinetics of Zn-hydroxyapatite (HA), and Zn-HA-iron (Fe) materials developed using microwave sintering process were investigated. The effect of the inclusion of HA and Fe in Zn on corrosion properties have been evaluated in the simulated body fluid solution. Further, the wettability test of the developed composites was performed to confirm the hydrophilic nature of the surface of all samples. Zn-3HA was found to have better hydrophilicity as compared to other samples. Increased corrosion rate and pH of Zn-5HA-2Fe samples were attributed to the addition of HA and Fe in the Zn matrix. The corrosion rate and weight loss rate from electrochemical and immersion testing of all samples were found in the order from highest to lowest: Zn-5HA-2Fe > Zn-3HA > Zn-3HA-2Fe > Zn. The highest cell viability nearly 100% was obtained for Zn-3HA samples, whereas other samples also showed sufficient biocompatibility to be utilized for biomedical applications.