Development of CaZn based glassy alloys as potential biodegradable bone graft substitute

We report the development of a CaZn based bulk glassy alloy (BGA) with combining properties of low Young's modulus, high fracture strength, good corrosion resistance and cytocompatibility, which make it be potential as biodegradable bone graft substitute. Compared to commonly investigated biodegradable metals, the Young's modulus of the BGA is closer to that of cortical bone, and its fracture strength reaches 600 MPa, which is 2 times higher than that of pure magnesium. The magnetic susceptibility of the CaZn based BGA is as low as 22.3 x 10(-6), which is compatible with magnetic resonance imaging (MRI) diagnosis. The BGAs also show slow degradation rate and good cytocompatibility. The new class of biodegradable CaZn based BGAs enriches the family of biomaterials, and the work has implications for developing new biodegradable alloys with active elements. The formation and the origins of excellent properties of the BGA are discussed. (C) 2011 Elsevier B.V. All rights reserved.