Researchers at UC Santa Barbara have successfully manufactured semiconductor material by using a process called "directed evolution," in which enzymes take shape by following Darwinian processes of selection. And this breakthrough could help scientists use DNA to grow unique and highly specialized materials for use in electronics and solar panels.
Daniel Morse and his colleagues were able to accomplish this feat of genetic engineering by using silicatein, a protein responsible for the formation of silica skeletons in marine sponges. The researchers were able to grow new mineral structures by directing the evolution of this enzyme.
The silicatein essentially acts as a template for the silica skeletons to control their mineralization. This process is very similar to what happens when animal and human bones are formed. It also happens to be the primary material in most commercially manufactured semiconductors.
By adding polystyrene microbeads coated with specific silicateins, and then putting it through a water-in-oil emulsion, the researchers essentially created a silicatein gene pool. The researchers dubbed this as "molecular sex" – the combination and recombination of various silacatine genetic materials. The process allowed the scientists to create a multitude of silicateins, and then select for the ones with desired properties.
Artificial selection did the rest: By selecting the beads that exhibited the mineralization the researchers were looking for, they could harvest the material, or have it evolve even further. Consequently, the process resulted in forms of silicatein not found in nature.
Their experiment essentially demonstrated how material structure can come about through evolutionary processes. And looking ahead, the researchers hope to evolve material performance in a functional device.
The paper, "Evolutionary selection of enzymatically synthesized semiconductors from biomimetic mineralization vesicles," was published in the Proceedings of the National Academy of Sciences.
Via Nanowerk. Image via Shutterstock/chang, hui-ju. Inset image via Ars Technica.