Scientists have developed a new kind of tiny motor capable of propelling itself through acidic environments - such as the human stomach - without any external energy source.
Dubbed "microrockets" by Joseph Wang and his team, the uber-mini devices travel at virtual warp speed - as a human would have to run at a brisk clip of 400 miles per hour to achieve an equivalent pace.
According to Wang, the self-propelled nano- or microscale motors offer very real applications in terms of targeted drug delivery, human imaging and monitoring industrial applications, such as semiconductor processing.
However, some versions of these small-scale motors are not self-propelled and require the addition of a fuel (commonly hydrogen peroxide). Other versions cannot withstand extreme environments such as the stomach, which is very acidic.
That's why the researchers developed a new, tubular microrocket that can move itself without added fuels in very acidic conditions. Indeed, Wang and his team tested the new microrocket in various acids and in acidified human blood serum. In such environments, the microrocket spontaneously produces bubbles of hydrogen gas, which propels it like the gases spewing out of a rocket's motor nozzle.
The microrocket is ultrafast — capable of moving farther than 100 times its 0.0004-inch length in just one second. In contrast to similar devices tested in recent years, the microrocket's interior is lined with zinc - which is considered more biocompatible and "greener" than other materials, plus, it spurs the generation of hydrogen bubbles.
It should be noted that Wang has also developed a microrocket version with a magnetic layer, allowing the research team to guide microrockets toward cargo for pick-up, transport and release.