Mankind has been long observing its surroundings – from the molecular choreography in the living cells to the glorious planetary movement in the Universe. Various micro- and macrocosmic observations and attempts to replicate natural systems allowed us to make things that are now difficult to live without. In the middle of the twentieth century the term for this scientific application of biological methods to the study and design of engineering systems was coined by Jack E. Steele. It was the dawn of Bionics.
Currently, it is a rapidly developing field, which integrates both science and technology knowledge in the development of innovative products, inspired by nature.
Nature, of course, was not chosen by accident. In the natural environment, a few billion years of evolutionary arms race optimized organisms to fit their natural environment as well as it is possible. Trial and error method related to naturally occurring mutations in the living organisms is to be held responsible for a natural optimization in biologically functioning structures. By studying these evolutionary products scientists are able to create technological solutions that are capable of making our life more comfortable.
One of the most famous and brilliantly simple discoveries made by copying nature is a hook-and-loop fastener, also known as the brand name VELCRO®. This tiny hook-and-loop system is widely used in children’s footwear and specific need outfits. “Hook-and-loop fasteners” were first observed in nature as things that could be adapted in household by Swiss engineer George de Mestral. In 1941, after hunting trip with a dog in the mountains of the Alps engineer drew attention to burdock burrs that clung to the fur and textile clothing.
Having examined these evolutionary adaptations for spreading the seeds under a microscope, G. de Mestral found that burrs cling to the fur like fishing hooks accidentally get attached to the fishing nets. After ten years of hard work, colleagues persuasion and search for the suitable materials and ways to produce the fasteners in the industry, George de Mestral finally mechanized hook-and-loop fasteners production and set the textile industry giant VELCRO®. Soon fasteners became indistinguishable part of NASA astronauts’ spacesuits, divers’, skiers’ and children’s clothing and footwear.
No less attention is paid to the aquatic lotus-like plants in the genus of Nelumbo. It was noted that water droplets just roll off the surface of these plants. This feature (also known on behalf of hydrophobicity) helps to prevent infections as pathogens – bacteria or mold – cannot stick effectively to the hydrophobic surface. Moreover, the leaf surface remains clean and the gases are capable of diffusion to and from the plant through the stomata freely.
This feature is essential for maintaining photosynthetic rate at constant value. Scientists soon realized that creating similar surfaces in the laboratories could lead to self-cleaning, longer lasting clothes. Scientists from all over the world began looking for materials that could reproduce a Lotus effect surface. One of them is the familiar cotton coated with the silica particles. Nowadays, hydrophobic paints and roof tiles, which are capable of bearing aesthetic appearance longer, have been created and successfully commercialized in the industry.
Researchers from General Electric (GE), a financial and industrial conglomerate, which dates back to the times of Thomas Alva Edison, successfully imitate the wing features of moths in the order of Lepidoptera. Butterflies’ wings are made up of thousands of tiny, overlapping chitin scales, causing the wings to shine. GE scientists discovered that the optical properties of the wings – coloration, brightness and optical clarity – depend on the airborne vapor chemical composition. Company engineers’ studies have shown that measuring the optical properties of such biological structures gives us the possibility to determine the composition of the ambient vapor. Investigators believe that the butterfly wing feature can be a possible precursor to the development of chemical leaks and explosives detection nano sensors.
In 2005, at the innovation exhibition in Washington, DC, Mercedes Company presented Mercedes-Benz Bionic car brand model designed to mimic the appearance of yellow boxfish (Ostracion cubicus). Boxfish, which is a part of coral reef ecosystems, was not chosen by chance – the fish has a strong, bony skeleton and streamlined form.
The Mercedes concept can boast under the same properties – the model car is aerodynamic, spacious, consumes 3.4 liters of diesel per 100-kilometer, reaches the speed of 60 km/h in 8 seconds and moves at the maximum velocity of 190 km/h. Such parameters of the car prove that the best innovator is the Mother Nature.
Controlled drug delivery
Many people, who have ever enjoyed the recreational benefits of natural bodies of water, should have noticed bivalve mollusks in the class of Bivalvia, strongly attached to the various types of substrates – deposits, branches, rocks or bottoms of the boats. After examining these mollusks closely, we can notice that bivalves are stick to the substrate because of strong, self-secreted threads, which form small plates at the surface of substrate.
As it turned out, one of these naturally occurring adhesive substances is DOPA, already used to treat Parkinson’s disease. An international team of scientists, led by Christian J. Kastrup, on the basis of the chemical composition of bivalve “glue” managed to create the adherent gel, which sticks to the inner wall of the blood vessels (endothelium). Drug molecules can be incorporated into such gel to control the gradual drug release into the blood stream and ensure local effect.
The researchers believe that this medical approach can help fighting against cardiovascular disorders such as atherosclerosis, inflammation, edema, thrombosis or hemorrhage. They claim that if the gel with the anticancer drug is attached to the blood vessels, which supply nutrients to the cancerous tumor, anticancer effect can be expected to increase as drug activity is more localized. Of course, a lot of experimental research still needs to be carried out in order to determine whether the therapy does not affect the human body in adverse manner.
Written by Edvinas Stankunas