Micro robots put drugs into the tumor

In a study published in Science Robotics, a team of scientists in China designed a new kind of bio-hybrid mini robot.

Tests with neutrobots have been performed quite successfully in mice. It can use intelligent biological camouflage and overcome difficult barriers to get closer to the source of the disease in the body and offer the best treatment. The Preeminence of New Micro Robots Microbots are nothing new, it’s like disguising robots into bacteria or using magnets to move them across blood vessels. But what sets Chinese scientists’ new micro-robot designs apart from the crowd is that it can overcome one of the body’s toughest biological barriers, the blood-brain barrier (BBB) ​​- a single layer. extremely high selectivity protection. Designed to stop pathogens and allow only nutrients to penetrate, BBB is the challenge of micro-robots that the body often considers an outside invader. It is very difficult for micro robots to cross this last line of defense and get closer to the hidden tumors behind it. One author of the above study is Professor Zhiguang Wu at Harbin Institute of Technology specializing in nanotechnology. The new micro-robots, he said, can overcome obstacles that hamper many conventional medical treatments. According to Professor Wu, “the passive diffusion of conventional drugs is subjected to a long, ineffective period of time and blocks biological barriers, which can lead to strong side effects. Meanwhile, the new swimming micro-robot / nano-robot, can move into hard-to-reach tissues using their propulsion, load different drugs and actively swim to diseased sites to transporting drugs ”. This is very important because when it comes to fighting cancer because the more targeted the treatment the better. It is especially true when it comes to brain tumors. Because the tumor is in a difficult position in the brain and BBB’s strong protection, drug treatment can be difficult, and removing the tumor requires brain surgery. Even then, usually only 90% of the tumor can actually be removed. In the past, micro robots were inspired by the way a bacteria or sperm move through the body. All light, acoustics and magnetic fields are used to propel them along the host’s body. Through it, a variety of biomedical tasks can be performed, including cutting the membrane, retaining the distributed drug in the gastrointestinal tract, and distributing the drug through the eye dropper. However, even though the researchers control the motion of these micro-robots more than typical drugs in the body, most micro-robotic designs still face one major hurdle: the body’s immune system, especially BBB. To fool BBB’s defense systems, scientists have designed a new micro-robot that is biologically camouflaged to “sneak through” the fence without being detected. The neutrobots are disguised and introduced into the bloodstream. How does the new micro robot work? The use of self-propelled, drug-dispensing micro-robots could open the door for scientists to get closer and more individual-based access to tumor treatment than oral or given medication. permission before. To treat glioma, a type of brain cancer, in mice, Professor Wu and colleagues have designed neutrobot-based micro-robots that can be controlled with a magnetic field. First, they created nanoparticles from a gel embedded with magnetic iron oxide particles, and the popular cancer drug paclitaxel. Next, these nanoparticles were encased in a disguised E. coli bacterial membrane. Disguised as harmful bacteria, these nanoparticles are submerged by in vitro mouse neutrophils much more easily than the bare nanoparticles that are not camouflaged. The researchers found that the camouflage also prevented drug leakage and made these particles less toxic to neutrophils. The research team tested the neutrobots’ ability to navigate and deliver drugs in vitro. Under the control of a rotating magnetic field, the neutrobots reach a speed of 16.4 µm / second – about 50 times faster than the natural neutrophil. By tracking the neutrobots under the microscope, the scientists can let them travel in complex directions on the artificial substrate. In their trials, the team showed that their neutrobots were able to successfully penetrate mouse BBBs to bring the drug into brain tumors. Despite these successes, scientists still have many things to do before they can be applied to humans. One issue that needs to be fixed, the authors explain, is how to better track each neutrobot as they pass through the body. Right now magnetic resonance imaging can track neutrobot groups as they move but cannot track individuals. “Our research has verified that treatment with neutrobots can prolong survival in mice with gliomas. Therefore, it may not be too long to bring stories about micro-robots in science fiction to reality, ”said Professor Wu.