Microsystems for drug and gene delivery

Microneedles and other structures have been developed for introducing therapeutic agents into tissues and cells. Microstructures for transdermal delivery hold the promise of pain-free drug injection. Electrodes integrated with microneedles can sense and monitor the effects of injected materials on tissues. Microprobes have been shown to be effective in transfecting cells through the delivery of DNA in experiments with both plants and animals. Microfabricated delivery devices have great potential for local delivery of drugs and genes where systemic administration presents serious safety concerns. In this paper we review recent progress in microdevices for delivering therapeutic agents, including microneedles, DNA transfection schemes, and intrasvascular drug and gene delivery systems.