A working finger-pressure sensor was built by self-assembling bacteria, a first by Duke University researchers.
In the new study, the researchers demonstrated the production of a composite structure by programming the cells themselves and controlling their access to nutrients, but still leaving the bacteria free to grow in three dimensions.*
As a demonstration, the bacteria were programmed to assemble into a finger-pressure sensor.
“This technology allows us to grow a functional device from a single cell,” said Lingchong You, the Paul Ruffin Scarborough Associate Professor of Engineering at Duke. “Fundamentally, it is no different from programming a cell to grow an entire tree.”
Nature is full of examples of life combining organic and inorganic compounds to make better materials. Mollusks grow shells consisting of calcium carbonate interlaced with a small amount of organic components, resulting in a microstructure three times tougher than calcium carbonate alone. Our own bones are a mix of organic collagen and inorganic minerals made up of various salts.
Harnessing such construction abilities in bacteria would have many advantages over current manufacturing processes. In nature, biological fabrication uses raw materials and energy very efficiently. In this synthetic system, for example, tweaking growth instructions to create different shapes and patterns could theoretically be much cheaper and faster than casting the new dies or molds needed for traditional manufacturing.
“Nature is a master of fabricating structured materials consisting of living and non-living components,” said You. “But it is extraordinarily difficult to program nature to create self-organized patterns. This work, however, is a proof-of-principle that it is not impossible.”
Micro-Scale suit tiles fabricated by genetically engineered metal affinity bacteria which assemble themselves in specific orderly arrays, then expire, leaving behind various metallic deposits which form all the metal shapes and microscopic circuits.