Wireless implantable and biodegradable sensors for postsurgery monitoring: current status and future perspectives.

In in vivo postsurgery monitoring, the use of wireless biodegradable implantable sensors has gained and is gaining a lot of interest, particularly in the case of monitoring for a short period of time. Indeed, the employment of biodegradable materials would allow to circumvent a secondary surgery for the devices removal. Additionally, the use of wireless communication for the data elaboration would consent to avoid the need of transcutaneous wires. In this manner it would be possible to prevent possible inflammation and infections associated with long-term and not wireless implants. It is expected that microfabricated biodegradable sensors can play a strong impact in acute or transient biomedical applications. However, the design of a high-performing electronic system, both fully biodegradable and wireless, is a very complex issue, particularly at small scales. The associated technologies are still in their infancy step and they should be more deeply and extensively investigated in animal models and, successively, in humans, to be clinically implemented. In this context, the present manuscript is aimed to provide a complete overview about wireless biodegradable implantable sensors, covering from the vital signs to be monitored, the involved wireless technologies, the biodegradable materials used for the production of the devices, the designed devices and their applications. Particularly both their adavantages and drawbacks are highlighted and the key challenges to be faced up, mainly associated to the fabrication techniques, and the control over degradation kinetics and biocompatibility of the device, are reported and discussed.