Intelligent Biomaterials as Pharmaceutical Carriers in Microfabricated and Nanoscale Devices

The emergence of micro- and nanoscale science and engineering has provided new avenuas for engineering materials with macromolecular and even molecular-scale precision, leading to diagnostic and therapeutic technologies that will revolutionize the way healthcare is administered. Biomaterials have evolved from off-the-shelf products to materials designed with molecular precision to exhibit the desired properties for a specific application, often mimicking biological systems. Controlling interactions at the level of natural building blocks, from proteins to cells, facilitates the novel exploration, manipulation, and application of living systems and biological phenomena. In addition, polymer networks with precisely engineered binding sites have been created via molecular imprinting, where functional monomers are preassembled with a target molecule and then the structure is locked with network formation. Nanoscale science and engineering have accelerated the development of novel drug delivery systems and led to enhanced control over how a given pharmaceutical is administered, helping biological potential to be transformed into medical reality. Micro- and nanoscale devices have been fabricated using integrated-circuit processing techniques, enabling strict temporal control over drug release. The advantages of these microdevices include simple release mechanisms, very accurate dosing, the capability of complex release patterns, the potential for local delivery, and possible biological drug stability enhancement by means of storage in a microvolume that can be precisely controlled. In particular, the development of polymer systems that are able to interact with their environment in a thermodynamically responsive manner has led to novel intelligent biomaterials and applications. Intelligent biomedical materials can be used for the delivery of drugs, peptides, and proteins; as targeting agents for site-specific delivery; or as components for the preparation of protein or drug conjugates. These intelligent materials are attractive options as functional components in micro- and nanodevices because of the ease with which recognition and actuation properties can be precisely tailored. Recent developments in intelligent materials and nano- or microdevices for drug delivery systems are the emphasis of this review, which addresses the use of intelligent biomedical materials as carriers for the development of novel pharmaceutical formulations.