Miniaturized drug delivery system TUDOS with accurate metering of microliter volumes
A miniaturized drug delivery system for accurate dosing of drugs for therapy of cancer is presented. The weight of the system is less than 8 grams. Silicon micropumps with a stroke volume of 88 nl, and blocking pressure of 6 bar, drive the system. A novel and accurate flow monitoring principle based on capacitance measurement was developed and implemented into the drug delivery system. To prevent free flow, a self blocking safety valve was adapted to the drug micropump. Moreover, further safety features like catheter blockage detection, pump failure detection, bubble detection and a bubble separator was realized. System control and driver electronics to supply the pumps with high voltage was realized on a tiny flex PCB and integrated. System tests showed, that test dosing volumes of 12 ml can be delivered reliably with accuracy better than 4 %. The system is now ready for animal trial (rat model) for a new cancer therapy approach.