Interfacing microsystems and biological systems

Micromechatronic systems integrate miniature precision mechanisms, actuators, sensors and embedded control. Their intrinsic features are electively suitable for application in the medical field, in particular when miniaturization, reliability and intimate interaction with the human body are required. Microsystems can be exploited for acute intervention or for permanent (short and long term) implant in the human body. This paper focuses on microsystems for permanent implant, and discusses their problems and perspectives with reference to some representative fields of application. Such fields include sensory substitution (such as microsystems for hearing aids, artificial eyes and artificial touch); internal organs substitution (in particular microsystems for drug delivery and micro bio-artificial organs); and neural prostheses (an example of regeneration-type neural interface is presented where axons regenerate through metalized holes microfabricated in a silicon dice). We conclude that medical applications of microsystems and micromachines may have a tremendous impact on the quality of medical care and become a very attractive industrial market, provided that some key technical problems are addressed and solved.