Silicon Microchips as Implantable Drug Delivery and Biosensing Devices

As pharmaceutical drugs become more potent, targeted, and complex, the importance of systems designed to precisely control the delivery of those drugs to the body increases. In addition, the lifetime of many implantable biosensors is limited by degradation of reagents or fouling of membranes and electrode surfaces. Therefore, our research and development efforts have focused on materials and devices that can: (1) store multiple drugs or biosensors, (2) protect them from the body until they are needed, and (3) controllably release the drugs from the device or expose the biosensors to body fluids on demand.

Microfabrication technology has enabled the creation of reservoir-based drug delivery and biosensing devices that meet these criteria. Microchips containing an array of sealed, drug-filled reservoirs have been developed and can be implanted in the body. Precise control over the release of drug from the device's reservoirs is enabled by integrating the device with pre-programmed microprocessors, wireless telemetry, or biosensors. Our group was the first to demonstrate both in vitro and in vivo, chronic on-demand release of drugs stored inside a microchip device.

This presentation will review the evolution of our implantable microchip technologies from prototypes created in an academic lab at MIT to products in commercial development.