Silicon microneedle electrode array with temperature monitoring for electroporation

This paper describes a system of silicon microneedle electrode arrays for electroporation with integrated temperature and fluidic system for drug delivery. In this research we have developed microneedle fabrication processes in standard silicon wafer utilizing wet and dry etch technologies. A method to manufacture electrodes and temperature sensors on the bottom of the microneedle array allows monitoring of temperature changes during electroporation close to the tissue. These local metal pads with interconnections for voltage supply have been realized by employing thick photoresist technologies combined with sputtering. This approach enables the fabrication of microneedle electrode arrays with integrated sensors for cancer therapy. Hollow microneedles allow drug delivery during electroporation. A uniform drug release through hollow microneedle electrodes into tissue improves the injection of drugs and therefore the efficiency of the treatment. The design of the fluidic system was simulated using CoventorWare to ensure the uniform release of fluid volume on every hollow needle. The fabrication process for a drug delivery system with silicon microneedle electrodes is presented.