Researchers at the University of North Carolina at Chapel Hill have demonstrated that nanoparticles designed with a specific shape, size and surface chemistry could deliver lower dosages of drugs to specific cells and tissues in the body and be more effective in treating tumors.

For instance, the scientists discovered that long, rod-shaped particles (diameter, 150 nanometers; height, 450 nanometers) were internalized by cells approximately four times faster than lower aspect ratio particles (diameter, 200 nanometers; height, 200 nanometers), and traveled significantly farther into the cells.