Visual H2 sensor for monitoring biodegradation of magnesium implants in vivo.

Abstract

Biodegradable Mg implants offer advantages over permanent implants such as stainless steel that are used for broken bone repair. Mg alloys gradually dissolve, avoiding the need for removal by a later surgery if complications arise. Here we report a visual H2 sensor that can be used in the research laboratory to monitor the corrosion process in vivo during animal testing of different Mg alloys. The sensor consists of a plastic sheet with a thin coating that changes color in the presence of H2 gas. The sensor is easily used by taping it on the skin over the Mg implant. The color change gives a map of the H2 level permeating from the degrading Mg through the skin above it. This low cost, simple method of monitoring the dissolution of biodegradable implants would greatly facilitate the development of the biodegradable materials, especially in animal studies where in vivo biodegradation is tested.