Chemotactic Micro- and Nanodevices.

Preparation of autonomous chemotactic micro- and nanomachines represents one of the most difficult challenges of modern materials science. To construct a device mimicking the behavior of many microorganisms, which evolved their chemotactic abilities during the millennia of evolution, places extreme demands on the imagination and abilities of researchers. However, with the chemotactic devices in hand, many novel and interesting applications of micromachines could be implemented. The introduction of an autonomous navigation, independent of the external control with electric, magnetic, or electromagnetic field is crucial for applications in environmental remediation and might be advantageous in medical applications. This Minireview summarizes the development in the field of chemotactic micro- and nanomachines, describes the trends in their construction, and compares the different approaches to their construction considering the areas of possible application of the devices.