BERN (Dispatches) -- Scientists have developed microscopic, hydrogel-based muscles that can manipulate and mechanically stimulate biological tissue. These soft, biocompatible robots could be used for targeted therapy and to help diagnose and prevent disease.
At Ecole Polytechnique Fédérale de Lausanne (EPFL), Selman Sakar's research team has developed micromachines able to mechanically stimulate cells and microtissue. These tools, which are powered by cell-sized artificial muscles, can carry out complicated manipulation tasks under physiological conditions on a microscopic scale.
The tools consist of microactuators and soft robotic devices that are wirelessly activated by laser beams. They can also incorporate microfluidic chips, which means they can be used to perform combinatorial tests that involve high-throughput chemical and mechanical stimulation of a variety of biological samples.
The scientists came up with the idea after observing the locomotor system in action.
Their system involves assembling various hydrogel components -- as if they were Lego bricks -- to form a compliant skeleton, and then creating tendon-like polymer connections between the skeleton and the microactuators. By combining the bricks and actuators in different ways, scientists can create an array of complicated micromachines.
With this method, scientists are able to remotely activate multiple microactuators at specified locations -- a dexterous approach that produces exceptional results. The microactuators complete each contraction-relaxation cycle in milliseconds with large strain.