A Passive Refillable Intraocular MEMS Drug Delivery Device

This paper presents the first passive implantable microelectromechanical systems (MEMS) device for targeted intraocular delivery of therapeutic compounds. In particular, this device addresses the treatment of chronic, difficult to reach diseases that affect the retina including retinitis pigmentosa, age-related macular degeneration, diabetic retinopathy, and glaucoma. The device is composed of three structural polymethyldisiloxane (PDMS) layers that are irreversibly bonded without the use of any adhesives. These layers form an integrated drug delivery device consisting of a refillable reservoir, tube, check valve, and suture tabs. This device requires a single implantation surgery and is capable of repeated delivery of multiple drugs. Characterization of the refillable reservoir and check valve performance is presented. Preliminary surgical implantation results of a mechanical test structure are also presented

Implantable MEMS drug delivery device for cancer radiation reduction

We present the first implantable MEMS drug delivery device that includes an electrochemical bellows pump, refillable drug reservoir, and dual regulation valve. Multiple drug pump configurations were fabricated, assembled, and tested. Delivery of agents for cancer radiation reduction was demonstrated. In vivo chronic delivery of radiation sensitizing agents in the form of small interfering (siRNA)-gold nanorod complexes (nanoplexes) directly to tumors induced in mice was achieved. Radiation therapy in conjunction with active drug pumping by electrolysis actuation resulted in significant reduction of colon cancer tumor (HT29) size (~50%) over diffusion-based delivery and intravenous injections. To our knowledge, this is the first MEMS drug delivery pump suitable for safe, efficacious, and local delivery of short half-life siRNA in vivo