Drugs are commonly delivered into the body through injection or pills but these traditional methods have their drawbacks. For one, there is no way to turn off the drug once it gets into the bloodstream. The medicine may also not be delivered on time and may come with unnecessary side effects.

Researchers, however, conducted an experiment that may eventually pave the way to solving the problems associated with traditional methods of drug delivery. They built a nanorobot out of DNA that can be switched on and off to release drugs within the body when needed and this tiny robot can be manipulated using mind control.

Study researcher Sachar Arnon, from the Interdisciplinary Center in Herzliya, Israel, and colleagues built the nanorobots in such a way that drugs can be tethered to them. The bots also have a gate with a lock that opens once it is heated using electromagnetic energy, which would then expose the drug to the environment.

The researchers developed a computer algorithm to analyze the activity of the brain and distinguish if it is at rest or doing mental calculations. They then attached a fluorescent drug to the nanobots, which they injected into a cockroach. The roach was then placed inside an electromagnetic coil.

In the experiment, scientists used electroencephalography (EEG) to measure the brain activity of a man while he did mental calculations or rested. Doing calculations triggered the electromagnetic coil to turn on, which then caused the drug to be released from the bot. When the volunteer stopped doing calculations, the signal was canceled, stopping the release of the drug.

Although the study is only a proof of concept, it may potentially change the way drugs are delivered particularly when it comes to treating mental health conditions. The researchers said that the algorithm can be trained to track other types of brain activities such as the states of the brain behind ADHD or schizophrenia.

If the algorithm could be set off not just by a mental calculation but by a particular mood or feeling, it could pave the way to a system wherein drugs are released only when they are needed.

"This technology enables the online switching of a bioactive molecule on and off in response to a subject's cognitive state, with potential implications to therapeutic control in disorders such as schizophrenia, depression, and attention deficits, which are among the most challenging conditions to diagnose and treat," the researchers wrote [PDF] in their study, which was released in the journal PLOS One on Aug. 15.