Scientists at Lawrence Livermore National Laboratory (LLNL) have developed a new method for 3D printing live bacteria in controlled samples. It will aid in the recovery of rare earth metals, wastewater treatment, uranium detection, and more.

Using a new technique that uses light and a resin filled with bacteria to produce three-dimensional patterned bacteria, scientists have successfully printed artificial biofilms. They resemble thin layers of microbial communities. The research team lured bacteria into 3D structures using LED light from a 3D printer of a stereolithographic microbial bioprinting machine (SLAM). A stereolithographic projection machine can print at high resolution on the order of 18 microns – almost the same thickness as the diameter of a human cell.

In an article published in the journal Nano Letters, the researchers proved that this technology can be effectively used to create structurally defined microbial communities. They demonstrated the applicability of such 3D-printed biofilms for uranium biosensitivity and rare earth bioprocessing and showed how geometry affects the characteristics of the created materials.

Previous methods of biofilm production in the laboratory did not give scientists the ability to control microbial organization in the film, which limited their ability to fully understand the complex interactions observed in bacterial communities in the natural world. The ability to bioprint microbes in three dimensions will enable LLNL scientists to better observe how bacteria function in their natural habitat and explore technologies such as microbial electrosynthesis. During this process, bacteria feeding on electrons (electrotrophs) convert excess electricity during off-peak hours. hours for the production of biofuels and biochemical products.