In vitro degradation of biodegradable metal Zn and Zn/Fe-couples and their application as conductors in biodegradable sensors

This paper reports a systematic in vitro degradation study of biodegradable metal zinc and zinc/iron (Zn/Fe)-couples, and explores the application of Zn/Fe-couples as the conductors in completely biodegradable sensors. By electrically connecting a bulk biodegradable metal (Zn) to a small, discontinuous amount of more active biodegradable metal (Fe), the degradation rate of the entire galvanic metal couple can be tailored by altering the Zn:Fe exposed area ratio without reducing the resistance of the conductor. This exploitation of galvanic corrosion couples to design the degradation of biodegradable metals suggests the potential for expanding the number of candidate degradable metals available for MEMS.