When it comes to medical robots, not so much. Actually, engineers for the University of Texas at San Antonio have just been awarded a Guinness Book of World Records certification for having developed the world's smallest medical robots.

The bots, created under UTSA's Multifunctional Electronics and Devices Research Laboratory's supervision by Soutik Betal, are sherical-appearing, yet really not quite globular, more oval, and with extremely minute cube-shaped magnetic cores. Each bot is only 0.0001 the thickness of a human hair.

Images showing officially world's tiniest medical robots (UTSA photos)

They are made to have a variety of medical applications. For instance, one type will be able to deliver cancer fighting medicines right to affected cells. They could discriminate between healthy and cancerous cells and then go after the latter with great accuracy. Imagine a letter carrier providing mail to precisely the correct address. In turn, the bots can find and use the cell's natural openings (their "mail slots") to provide requisite anti-cancer drugs. Thanks to their magnetic cores, these nano-robots can be moved exactly where needed via remote electromagnetic fields.

Medical scientists have concerns whether or not the tiny robots' real interventions will be accepted by our bodies' natural defenses. Some believe their little magnets may stimulate negative reactions by our immune systems. These and other potential challenges mean even such microscopic bots may not be moving substances around inside us for a few more years.

Other nano-technology uses might one day include surgery on a level so minimally invasive as to allow for much more rapid recoveries than are now possible, moving beneficial "cargo" about tissues and the bloodstream, or providing advanced imaging and even enhancing other senses right at the sites of trauma, chemical deficiencies, or disease.

Primary source: San Antonio Engineers 'Officially Amazing' After Building World's Smallest Medical Robot. Bonnie Petrie in Texas Public Radio, tpr.org; August 31, 2018.