Cell-Sized Robots Sense Their Environment

Colloids — insoluble particles or molecules anywhere from a billionth to a millionth of a meter across — are so small they can stay suspended indefinitely in a liquid or even in air. Robots about the size of a human egg cell were created that can sense their environment, store data, and carry out computational tasks. They consist of tiny electronic circuits made of two-dimensional materials, piggybacking on colloids. By coupling these tiny objects to complex circuitry, the researchers hope to lay the groundwork for devices that could be dispersed to carry out diagnostic journeys through anything from the human digestive system to oil and gas pipelines, or perhaps to waft through air to measure compounds inside a chemical processor or refinery.