Implantable BioMEMs

Microelectromechanical systems (MEMS), tiny devices crafted using microchip technology, have appeared in a number of settings; examples include micron-sized motors, gears, pumps, and detectors. One would also like to use MEMS in implantable medical applications, but bio-compatibility has been a problem. To address this obstacle Tejal Desai at the University of Illinois-Chicago (tdesai@uic.edu, 312-413-8723) has developed a capsule containing insulin-secreting cells. The capsule is covered with pores as small as 7 nm which allow the release of insulin while blocking the entrance of antibodies thrown up the immune system to counteract the transplanted cells. Desai, who has tested her capsules on mice and rats, will report her new results with nanopore capsules (including also compartmented 100-micron chips for drug delivery) at a meeting co-sponsored by the AVS Science and Technology Society in San Francisco, Oct 29-Nov 2; see Desai's abstract and her university website.)