In vitro corrosion behavior and cytotoxicity property of magnesium matrix composite with chitosan coating

Mg-6%Zn-10%β-Ca3（PO4）2 composite was prepared through powder metallurgy methods with different chitosan coatings on its surface. The properties of the chitosan coatings on the surface of Mg-6%Zn-10%β-Ca3（PO4）2 composite, such as the adhesion ability, the corrosion behavior and the cytotoxicity properties, were investigated, and the microstructure of the chitosan coating was observed by scanning electron microscope（SEM）. The results show that chitosan coating improves the corrosion resistance of the magnesium composite specimens significantly. Mg-6%Zn-10%β-Ca3（PO4）2 composite specimens exhibit good corrosion resistance and low p H values in simulated body fluid（SBF） at 37 °C in the immersion test with 7-layer chitosan coating whose relative molecular mass is 30×104 Da. The cytotoxicity tests indicate that Mg-6%Zn-10%β-Ca3（PO4）2 with chitosan coating is nontoxic with a cytotoxicity grade of zero against L-929 cells, which is better than that of uncoated composites.