Bioadhesive Microde vices for Drug Delivery: A Feasibility Study

A variety of delivery systems have been devised to improve the oral bioavailability of drugs including enterically coated tablets, capsules, particles, liposomes, and others. Microfabrication technology, however, may offer some potential advantages over conventional drug delivery technologies. This technology, combined with appropriate surface chemistry, may permit the highly localized and unidirectional release of drugs, permeation enhancers, and/or promoters. In this study, we demonstrate the fabrication of prototype reservoir containing microparticles and a surface chemistry protocol that can be used to bind lectin via avidin-biotin interactions to silicon microparticles. In vitro studies show enhanced bioadhesion of these lectin conjugated microparticles. Such an approach can be used to improve the absorption of pharmacologically active biopolymers such as peptides, proteins and oligonucleotides into circulation at targeted sights in the GI system. Moreover, the use of microfabrication allows one to tailor the size, shape, reservoir volume, and surface characteristics of the drug delivery vehicle.