Nanotechnology Focus Shifts to Shape, Not Size

The advent of nanotechnology applications in medicine, especially in drug delivery, was motivated by the belief that minimizing the size of drug delivery vehicles would optimize their effectiveness. A research team from the University of North Carolina- Chapel Hill made a surprising discovery about the effectiveness of nanoparticles that contradicts such traditional beliefs. According to Joseph DeSimone and his research team, it’s not size that determines the immune response to nanoparticles, but rather their shape. Research suggests that rodlike particles are able to infiltrate target cells more effectively, largely due to decreased macrophage response. Conventional spherical nanoparticles are easily picked up by macrophage activity because they don’t require much expansion by the specialized immune cells. Therefore, engulfing elongated shapes from the side is much harder. It’s also very unlikely that the macrophage would attack the nanoparticle from one end because it is only a small fraction of the particle’s total surface area. The exact proportions of the rodlike nanoparticles can vary to target specific cells or block entrance into areas subject to damage from a certain drug.

This revolutionary discovery will have a profound impact on the nanotechnology industry. The focus now has shifted from making medical nanobots smaller and smaller to specifying a shape for each unique application. More research is required to determine the ideal shape for each target cell type, but the new information will help bioengineers successfully implement nanotechnology in the future.

Scientific American Article:
http://www.sciam.com/article.cfm?id=size-shape-matter-nanotech-drug&page=2

~Angie Burrer
Section 501