Skipping along the gut
Getting the drug directly into the target area can eliminate unpleasant and dangerous side effects, such as hair loss or gastrointestinal bleeding, by reducing the dosage of the drug and lack of contact with other, non-targeted organs.
In a study published in the journal Micromachines, a group from Purdue University for the first time demonstrated a micro robot moving with the help of straight and lateral somersaults on the uneven surface of the intestine in vivo. Since the micro robot is too small to carry a battery, it receives power and remote control from the outside using a magnetic field. The magnetic field safely penetrates into various types of media, which is important for the possibility of using these robots in the human body.
The researchers chose the colon for in vivo experiments because it is easier to get into. Live mice were injected with a saline solution with micro-robots through the rectum under anesthesia and watched in real time with the help of ultrasound equipment how it moves.
The contents of the colon and the robot were moving in opposite directions, and it was not easy to achieve this. An external rotating magnetic field created near the animal caused the microrobot to rotate and move in the right direction, even if it was back to peristalsis. The researchers found that micro-robots can also get into the colon cut out of pigs, whose intestines are similar to human ones.
The research team evaluated the ability of the micro robot to transfer and release the drug in a container with saline solution. To do this, they coated the micro robot with a fluorescent drug simulator, which he successfully transferred through the solution before the load was released.
The results mean that it is potentially possible to direct the micro robot to a target area in the body, leave it there, and then allow the drug to slowly come out. And since the microrobot has a polymer coating, the drug is not released until it reaches its destination.
The researchers believe that micro-robots can also act as diagnostic tools, reducing the need for minimally invasive colonoscopy for material sampling.
And finally, magnetic micro robots, which are made of inexpensive polymer and metal, are non-toxic and biocompatible.
A video with micro-robots jumping on different surfaces can be viewed on YouTube.
Article by E.E.Niedert et al. A Tumbling Magnetic Microrobot System for Biomedical Applications is published in the journal Micromachines.
Aminat Adzhieva, portal "Eternal Youth" http://vechnayamolodost.ru based on materials from Purdue University: All-terrain microrobot flips through a live colon.