Technology frontier: 3D printing can be achieved by bacterial groups
Roberto Leonardo, a professor of physics at the University of Rome, developed a series of tiny motors that powered with bacteria and lasers and began to turn.
Nano-scale 3D printing technology is not new, but related applications are still being updated. One of the technologies known as "two-photon lithography" became popular, and many aesthetic models were produced using this technology, including microscopic racing, space shuttles, and even ancient Roman sculptures.
Although researchers also want to apply this technology to the medical field, so far, from a mechanical point of view, the results have been limited. For example, a research team has used 3D printing to create a nanodevice called a "shark" that can move freely in a magnetic field, while other research groups are working on developing new geometries to increase the probability of successful delivery of targeted drugs.
Past research has proven that nanotechnology has great potential in certain applications, and the printed objects have unexpected medical effects. Scientists at the University of Rome used this feature to develop micromotors powered by light-controlled bacteria. In the experiment, Leonardo's team showed how the 36 electric machines work in unison, indicating what the future of 3D printing micromachines is.
Leonardo said that using modern tools such as nanotechnology and microfabrication, researchers can make better and better micromachines. With a 3D printed two-photon lithography system, any shape can be printed, but if you want mechanical motion to move autonomously, you need to find power. A mechanical system made of semi-solid resin, combined with an assembly tool such as a holographic diaphragm, can use a laser to manipulate tiny living bodies.
In the special motor introduced by the Leonardo experimental team, the researchers used genetically engineered E. coli. In the micro-motor array, each motor is etched with 15 micro-chambers. When the researchers drop a drop of bacteria containing thousands of swimming, they will swim into the micro-chamber one by one, including the flagella. outer. Under the combined force, the bacteria turned into a tiny "propeller", rotating the 3D micromotor like a running water wheel.
Since the modified E. coli also has its own swimming style and behavioral characteristics, the researchers also deliberately built a small ramp on the motor, tilting it at a 45-degree angle to maximize the torque, and rushing it into the micro-chamber to make the flagella Freely whip outside the chamber to propel the movement of a single motor rotor. The drawback of this method is that the thrust generated by the bacteria is intermittent, and it takes about 1 minute for the motor to rotate once, and sometimes the direction of movement of some of the rotors is reversed, which is vain.
In order to gather and control the bacteria, the researchers illuminate the motor system with a laser every 10 seconds, so that every component in the system can be aligned. In the past, the scientific community used to use electric or magnetic fields to control bacteria, but it was expensive and difficult to manufacture. The use of light to control the motor system is simple to operate and low in cost, and allows bacteria to respond to different signals in the environment.
Leonardo pointed out that the basic unit of life is cells, and medical diagnosis can begin by collecting individual cells. At present, human research is only the beginning. Independent researchers always make unremitting efforts in the fields of physics, engineering, biology, etc. However, from the perspective of nanotechnology, if different fields of research are put together, society can get the most benefit.