Figure of the month: 30

What had already been the subject of science fiction films in the 1960s is now close to becoming reality: a research team at the Technical University of Munich, Germany, has developed a one-of-a-kind smart microrobot able to specifically control and stimulate individual cells in the human body. Initially, the robots, which are only 30 micrometres long (equalling 0.003 centimetres) will be used to examine cancer cells more thoroughly than ever before. The knowledge thus gained could be used to develop more effective therapies.

Microrobots made from algae, fluorescent rhodamine-B and gold
 

The so-called TASCI (Thermally Activated Cell-Signal Imaging) microrobots developed under the leadership of Professor Berna Özkale Edelmann are driven and controlled by laser beams. This is made possible by irradiating the 25 x 90 nanometre gold cylinders integrated into the microrobots, which enable targeted movement through heating. The gold nanoparticles can be heated up extremely fast, by 5 degrees Celsius in just a few milliseconds, and cool down just as quickly. The tiny gold cylinders can be heated to a maximum of 60 degrees Celsius. The temperature changes not only enable the microrobots to smoothly navigate through the human body, but also to activate specific individual cells by heating them. The automatic temperature equalisation of the gold nanocylinders following their heating allows the microrobots to move by up to 65 micrometres per second.

For now only in vitro, in future directly in the human body
 

Initially, the innovative technology will be used primarily to fight cancer outside the human body – in vitro. In the future, however, the microrobots will be used directly for cancer therapy, e.g. by transporting and launching medical agents straight to the cancerous cell.