Introducing novel bioabsorbable Zn-Ag-Mg alloys intended for cardiovascular applications

Zn is considered an excellent candidate material for endovascular applications due to its outstanding combi-nation of biodegradability and biofunctionality. The present work introduces two novel Zn-Ag-Mg alloys with highly desirable mechanical, corrosion, and biological performance. Microstructural characterization revealed a significant grain refinement as a consequence of alloying (Ag) in conjunction with an adequate thermo-mechanical processing route for both alloy systems. Tensile test results indicated that the best mechanical properties in terms of yield strength (YS), ultimate tensile strength (UTS), and elongation to failure (% E) were achieved for the unidirectional rolled (UR) Zn-6Ag-0.5Mg alloy with values of similar to 300 MPa, similar to 370 MPa, and similar to 40%, respectively. However, a superior UTS was exhibited for the Zn-10Ag-0.9Mg alloy with a value of similar to 430 MPa. The observed corrosion rate (CR) trend measured by potentiodynamic polarization test was Zn-6Ag-0.5Mg = 2.232 (mm/year) > Zn-10Ag-0.9Mg = 1.405 (mm/year) > pure Zn = 0.935 (mm/year). When static im-mersion tests were performed, it was observed an unexpected static corrosion rate (SCR) with the following trend: pure Zn = 0.14 (mm/year) > Zn-6Ag-0.5Mg = 0.07 (mm/year) > Zn-10Ag-0.9Mg = 0.05 (mm/year). Moreover, the indirect cell test showed grade 0 of cytotoxicity at 10% and 1% of metal extracts for both ternary alloys. Finally, the proposed alloys possess excellent hemocompatibility characteristics indicating an ideal balance between mechanical integrity and biocompatibility required for the intended application.