Magnetic Biohybrid Robots as Efficient Drug Carrier to Generate Plant Cell Clones.

Micro/nanorobots represent a new generation of micromachines that can accomplish various tasks, such as loading and transporting specific targets or pharmaceuticals for a given application. Biohybrid robots consisting of biological cells (bacteria, sperm, and microalgae) combined with inorganic particles to control or propel their movement are of particular interest. The skeleton of these biohybrid robots can be used to load biomolecules. In this work, the authors create biohybrid robots based on tomato plants by coculturing ferromagnetic nanoparticles (Fe 3 O 4 ) with tomato callus cells. The tomato-based biohybrid robots (Tomato-Biobots) containing Fe 3 O 4 nanoparticles  are driven by a transversely rotating magnetic field. In addition, biohybrid robots are used to load vitamin C, to generate clones of tomato cells. It is shown that the presence of Fe 3 O 4  does not affect the growth of tomato callus. This study opens a wide range of possibilities for the use of biohybrid robots@Fe 3 O 4  to deliver conventional agrochemicals, including fertilizers, pesticides, and herbicides, and allows for a gradual and sustained release of nutrients and agrochemicals, leading to precise dosing that reduces the amount of agrochemicals used. This conceptually new type of micromachine with application to plants and agronomy shall find broad use in this field.