Happy New Biomimetics Year
The variety of design applications coming from the imitation of natural solutions continues to be astonishing.
Hope for sensitive teeth: When is it time to see the dentist? At 2:30 (tooth hurty). If you have sensitive teeth like 3 out of 4 people, there may be a biomimetic solution coming. Sensitivity occurs when dentin at the gum line erodes, leaving nerves exposed to hot, cold, sweet or sour signals. PhysOrg and Science Daily, echoing a press release from the American Chemical Society, announced a way to rebuild enamel and dentin, taking a clue from mussels. Mussels build a waterproof adhesive to secure themselves to the rocks. “Taking inspiration from nature,” a team “reasoned that it could help keep minerals in contact with dentin long enough for the rebuilding process to occur.” They have invented a “gooey substance” that allows the dentin and enamel to grow together (see picture on PhysOrg). This solution would be far better than the current band-aid treatment of brushing with special toothpaste that deadens the nerves. Instead, the adhesive could allow the teeth to be reconstructed for good.
Pearl of great price: The beauty of pearl and mother-of-pearl (nacre) goes beyond its attractiveness in jewelry. The material is also desirable for its durability against cracks. Biomimetics engineers would like to imitate the construction of similar materials, but understanding how the mollusk does it is a prerequisite. It looks like imitation will be a way off; in a PNAS paper, researchers described how they”identified 80 shell matrix proteins, among which 66 are entirely unique.” Although they believed that shell-making was key to the “evolutionary success” of mollusks, they didn’t describe how these unique proteins arose, each one being a highly improbable outcome for a blind evolutionary process (see online book). The French team said,
This is the only description of the whole “biomineralization toolkit” of the matrices that, at least in part, is thought to regulate the formation of the prismatic and nacreous shell layers in the pearl oysters. We unambiguously demonstrate that prisms and nacre are assembled from very different protein repertoires. This suggests that these layers do not derive from each other.
Imitating rapid steroid synthesis: Researchers at Scripps Institute are achieving “a feat … that only nature could make on a large scale” – the synthesis of polyhydroxylated steroids. “”These compounds. used in heart-failure medications and other drugs, have been notoriously problematic to synthesize in the laboratory,” PhysOrg reported. The work “points the way to a scalable formation and modification of a variety of useful compounds that had been obtainable in significant quantities only from plants or animals.” They reduced the number of steps from 41 to 21, making nature’s feat still look superior.
Bioinspired catalysts: Nature makes it look so easy. “Naturally occurring metalloenzymes have long been recognized as attractive catalysts for aerobic oxidations because they can operate under mild conditions with complete chemoselectivity,” Science Magazine said. “Simulation of the function of these enzymes has led to the discovery of many biomimetic oxidation catalysts.” Martine Largeron and Maurice-Bernard Fleury described progress in this dynamic research field. Researchers aren’t yet close to catching up with what living cells do every day:
Many challenges remain, including the development of biomimetic catalytic systems that operate effectively at room temperature with ambient air rather than pure molecular oxygen. The development of recyclable heterogeneous nanocluster catalysts that contain biocompatible rather than rare and precious metals would also be welcome. From a more general viewpoint, mimicking the function of amine oxidase enzymes would provide environmentally friendly organic synthesis because air is the cheaper and less polluting stoichiometric oxidant.
Mitochondria-inspired fuel cells: Inspired by how cellular organelles like mitochondria and chloroplasts harvest sunlight so efficiently, researchers at the University of Reading have built nanowire networks with vastly increased surface area that can reside on plastic substrates, promising fuel cells and other products that are more efficient, cheaper, lightweight, and environmentally friendly. PhysOrg headlined this, “Nanomaterial inspired by nature paves way for greener energy.” If you don’t mind the goofy music, a video clip shows the manufacturing process.
Living buildings: Imagine buildings of the future hosting lichens and mosses that can absorb excess C02. That’s becoming an option, reported Science Daily, with a drawing of a building with a “vegetated facade” making the most of the sunlight. The new material, designed at a university in Barcelona, Spain, “offers environmental, thermal and aesthetic advantages over other similar construction solutions.” It also improves the thermal comfort of people inside. “The innovative feature of this new (vertical multilayer) concrete is that it acts as a natural biological support for the growth and development of certain biological organisms, to be specific, certain families of microalgae, fungi, lichens and mosses.” The layered structure captures rainwater for use by the organisms, and as they grow, the buildings will change in color over time. The researchers see their patented concrete being used for renovating buildings, creating “vertical gardens” and designing architectures that blend into the landscape.
Everyone can love biomimetics. Many of the above are unique stories, not mentioned here before. Faster, better, cheaper – nature shows us the way. Darwin-talk drops out of the discussion when the focus is on natural design we can use to improve our lives.