MEMS-based Implantable Drug Delivery System

Implantable devices are currently used regularly for chronic pain relief, cardiac pacemakers, arterial infusion for cancer and insulin delivery. A MEMS based implantable drug delivery system (IDDS) integrating a subcutaneous reservoir, an in plane silicon pump and associated circuitry for local or centralized delivery of therapeutic agents for chemotherapy is proposed. System configurations, flow rate analysis and applications are presented. There are many advantages to the MEMS based IDDS employing the well established techniques of intravenous therapy. The reservoir can be customized providing flexibility. This combined with the small size of the pump provides workable solution for implantable drug delivery systems. Telemetry allows wireless monitoring and control of the drug flow rate, reservoir levels and battery recharging. The flow rate capability of the pump is evaluated in the presence of venous pressure. A combination of finite element analysis and lumped model approximations show that the average flow rates up to 85 μl/min are achievable.