Biological applications of high aspect ratio nanoparticles

Abstract

This review describes recent advances in nanomaterials fabrication that have led to the synthesis of high aspect ratio particles on nanometer length scales. The elongated structure of these materials often result in inherent chemical, electrical, magnetic, and optical anisotropy that can be exploited for interactions with cells and biomolecules in fundamentally new ways. We briefly describe the synthetic procedures that have been developed to fabricate nanorods, nanowires, and nanotubes. We summarize literature reports that describe the use of high aspect ratio nanoparticles for biological sensing, separations, and gene delivery. We emphasize the recent discovery of single nanowire field-effect transistors that may revolutionize biological sensing and yield extremely low detection limits. Separations technology with chemically modifiable nanotube membranes and with magnetic nanowires that can be tailored to selectively interact with molecules of interest is also described. Other areas of biotechnology that have been improved by the integration of high aspect ratio nanoparticles are also described.