Nano/Microscale motors: biomedical opportunities and challenges.

Artificial nano/microscale machines hold great promise for diverse future biomedical applications. This Perspective summarizes recent advances in microscale motors, as exemplified by Hoyos and Mallouk in this issue of ACS Nano, and highlights the challenges and opportunities in translating this remarkable progress toward practical biomedical applications. Various areas of medicine, including targeted drug delivery, precision nanosurgery, biopsy, cell sorting, or diagnostic assays, would benefit from recent developments of efficient fuel-free and fuel-driven nano/microscale machines. Newly introduced ultrasound-driven propulsion mechanisms greatly enhance the prospects for these biomedical applications. With continuous innovation and attention to key challenges, we expect that man-made nano/microscale motors will have profound impact upon different medical areas.