Biomedical Nanotechnology Lecture 2: Nano-Biomimicry PDF

BIOMEDICAL NANOTECHNOLOGY LECTURE 2: NANO-BIOMIMICRY Dr.P.GOPINATH DEPARTMENT OF BIOTECHNOLOGY 1  Contents What is biomimicry? How nanosciences uses biomimicry? Gecko, moth eyes, butterfly, peacock, lotu...

BIOMEDICAL NANOTECHNOLOGY LECTURE 2: NANO-BIOMIMICRY Dr.P.GOPINATH DEPARTMENT OF BIOTECHNOLOGY 1  Contents What is biomimicry? How nanosciences uses biomimicry? Gecko, moth eyes, butterfly, peacock, lotus leaf, toucan beaks etc.. 2  Biomimicry Most of the problems humans face today are also faced by other organisms. Over the course of evolution, many organisms gained more efficient ways to use their environment. The organisms that are alive today are the successful models or products of evolution. We could learn a lot from nature when it comes to solving our challenges in a sustainable way. 3 Biomimicry – Simple example 4  Nano in nature - Gecko feet Gecko’s are good climbers Gecko feet are covered with nano-size hairs that use intermolecular forces (Van der Waals forces), allowing the lizards to stick firmly to surfaces. https://robotics.eecs.berkeley.edu/~ronf/Gecko/ 5  Biocompatible patches By replicating this scientists have developed an adhesive that can seal wounds or patch a hole caused by a stomach ulcer. The adhesive is elastic, waterproof and made of material that breaks down as the injury heals. http://www.geckobiomedical.com/ 6 Light activated: The adhesive, which is based on two biomolecules, glycerine and an acid, is activated by UV light. Wet adhesive: Many adhesives lose their potency in a wet environment. This one does not. The tissue surface need not to be dry. The adhesive works in the presence of blood without reacting chemically. Biocompatible patches: They are like tissue velcro, growing into the tissue and holding it together. The idea is that the patches fill a wound and are biocompatible so don‘t need to be taken off. 7 Gecko tape Gecko Tape 8  Gecko shoes So, making use of these nanostructures found in setae, the grip of shoes can be improved during mountaineering. GEKKO TRECKKING SHOES. 9  Gecko shoes This approach may provides better stability on rocky terrain and prevent slipping while you climbing or descending. Then scaling new heights will be no more difficult.  Spider‘s foot The strength of the suction in a spider‘s foot is due to all of the small van der Waals forces at the nanoscale Hairy spider toes Setules on hairs pulling at the same time. So, why isn‘t it stuck in one place? It lifts its leg so that the setules lift successively, not all at once. Imagine astronauts using the same idea for spacesuits that help them stick to the walls of a spacecraft, I hope they just like a spider on the ceiling. invent that http://www.eurekalert.org/pub_releases/2004-04/iop-smb041504.php suit soon!  Self-cleaning windows from moth eyes University College London (UCL) researchers have developed a revolutionary new type of ‗smart‘ window. Self-cleaning: The window is ultra-resistant to water, so rain hitting the outside forms spherical droplets that roll easily over the surface – picking up dirt, dust and other contaminants and carrying them away. Energy-saving: The glass is coated with a very thin (5-10 nanometre) film of vanadium dioxide which during cold periods stops thermal radiation escaping and so prevents heat loss; during hot periods it prevents infrared radiation from the sun entering the building. Anti-glare: The design of the nanostructures also gives the windows the same anti-reflective properties found in the eyes of moths and other creatures that have evolved to hide from predators. http://www.ucl.ac.uk/news/news-articles/0116/200116-self-cleaning-windows/ 12 Chameleon-like material changes color on demand Researchers at the University of California at Berkeley developed an ultra- thin material that can change color on demand by bouncing back light on the nanoscale level. The ―chameleon skin‖ material actually changes color when flexed, or when a small amount of force is applied to the surface. Tiny ridges — smaller than a wavelength of light — are etched into a layer of silicon film one thousand times thinner than a human hair. The silicon layer, approximately 120 nanometers thick, is flexible and functions as a skin that can be adhered to other surfaces. Spacing of the ridges produces different colors. On top of that, the material is highly reflective — bouncing back up to 83 percent of incoming light, which makes it quite efficient at producing those colors. http://www.seeker.com/chameleon-like-material-changes-color-on-demand-1769606251.html#mkcpgn=rssnws1 13  Learning anti-microbial physics from cicada The wings of this small fly display bactericidal nanoscale pillar structures. Each of these pillars is a pike of several tens of nanometers in diameter and is separated from other pikes at regular nanometer intervals. Densely packed on the wing surfaces, these pillars arrange into nanopatterns which pierce the membranes of bacterial cells on contact, tearing bacteria apart. https://phys.org/news/2014-11-anti-microbial-physics-cicada.html http://www.mnn.com/earth-matters/animals/blogs/cicadas-antibacterial-trick-may-help-humans 14  Inspiration from fish scales Fish repel oil by trapping water within Transparent surfaces for repelling oil their scales to create a self-cleaning, oil- underwater made from silica repellent coat and prompted part of the idea behind the work. Researchers in China have taken inspiration from fish scales and skeleton flowers to make a transparent underwater surface that stays clean by repelling oil. In air (a) the surface is misty but underwater (b) it has high transparency and repels oil https://www.chemistryworld.com/research/fish-and-flowers-inspire-diving-goggle-material/8440.article#.VTDW1eHe7e4.twitter 15  Skeleton flower (Diphylleia grayi) In air skeleton flower‘s petals appear white, but on contact with water they become transparent. This change is not due to a pigment but loose cell structure in the plant petals. On sunny days the air–liquid interface of the petals causes diffuse reflectance, endowing the petals with a white colour, whilst on rainy days water enters the petals, yielding a The skeleton flower on a sunny day (a) water–water interface, increasing light and in the rain (b) transmission so they turn transparent. https://www.chemistryworld.com/research/fish-and-flowers-inspire-diving-goggle-material/8440.article#.VTDW1eHe7e4.twitter 16  Transparent surfaces for repelling oil Light scattering means that many synthetic oil- repellent surfaces are opaque, limiting their use. A transparent, oil-repellent surface would have applications in biology and underwater optics, including in diving goggles and cameras. By using femtosecond laser ablation to create rough nanostructures on a silica glass surface, reseachers have made a surface that combines both of these systems – it turns transparent and Laser-induced micro/nanostructures in the repels oil when in water. glass mimic fish scales and plant cells https://www.chemistryworld.com/research/fish-and-flowers-inspire-diving-goggle-material/8440.article#.VTDW1eHe7e4.twitter 17  Nano in peacock feathers The iridescence of peacock feathers is fascinating because of their range of colors and their brightness in a filament. Color can arise from wavelength selective absorption and wavelength selective reflection. Yoshioka and Kinoshita found that the pigmentation in peacock feathers, instead of reflecting light, serves ―...to absorb the randomly scattered light and [thus] make vivid the interference color. Yoshioka, S. and Kinoshita, S. 2002. Forma, 17, 169-181. 18 NANOPHOTONIC CRYSTALS 19  Color in Butterfly Wings Butterfly wing scales in increasing magnitude Butterfly wings are layers of nanoparticles separated by layers of air. The thickness of the layers changes the colors that we see. http://www.ntcresearch.org/pdf-rpts/AnRp05/M03-MD14-A5.pdf http://pubs.acs.org/cen/critter/butterfly.html http://jbe.jlu.edu.cn/free/v1/i4/207.pdf 20 21  How do we mimic wing colors? The layered nanostructure of the butterfly wing inspires scientists to develop textiles by assembling nanoparticles into layers from the ‗bottom up‘. 22  Butterfly Wings Have you noticed that the colors on a butterfly wing change based on the angle you look at them? – This happens because the wings are made up of nano-thin layers that cause light to reflect differently Scientists and engineers are using this to hopefully develop a new type ―intelligent‖ solar panel. http://www.spice.centers.ufl.edu/Modules.html  Living LED‘s Butterflies figured out how to emit light 30 million years ago. Fluorescent patches on the wings of this African swallowtail butterflies work in a very similar way to high emission light emitting diodes (LEDs). http://news.bbc.co.uk/2/hi/science/nature/4443854.stm  Butterfly wings inspire better sensors Researchers at GE Global Research discovered that the nanostructures on the wing scales of Morpho butterflies have acute sensing capabilities. This could allow scientist to build sensors that can detect heat and also as many as 1,000 different chemicals. Morpho butterfly wings could inspire the next Morpho butterfly wings change their natural color (A) after exposure generation of thermal imaging sensors. to ethanol (top B) and toluene https://www.pddnet.com/news/2014/04/photos-day-butterfly-wings-inspire-better-sensors 25 Wings are colorful and hydrophobic! Water droplet Look, Mom, I’m dry! Notice the butterfly‘s wing in the picture isn‘t getting wet? The butterfly can thank its lucky stars or, better yet, its nanoscales. http://jbe.jlu.edu.cn/free/v1/i4/207.pdf More information can be found on the web at http://www.exploratorium.edu/ronh/bubbles/bubbles.htm Activities can be found at http://www.lessonplanspage.com/ScienceExAddPenniesToFullGlassMO68.htm or http://www.iit.edu/~smile/ph9205.html  How these surfaces work ? Because of the nanostructures on a butterfly wing or other hydrophobic surface, a waterdrop forms into a ball, rolling from the surface and taking the dirt with it. This image shows the nanostructures on a wing surface. Because of the waxiness of the surface, the waterdrop rolls – rather than slides – down the surface with little friction. The drop collects dirt and bacteria on its way, and in effect cleans itself. Nanostructures, (tiny waxy "spikes―), on the surface prevent a water droplet from reaching the underlying material. It rolls off the waxy tips which are very small compared to the water = water droplet. The force of the rolling water is greater than the force of attraction between the surface and dirt or bacteria which = dirt allows it to be washed away.  Lotus Leaf Certain leaves have a particular surface structure that makes them difficult to get wet. Water beads up into little droplets due to nano- size ridges and wax coated hairs. This phenomena is called the lotus effect. – Engineers are making clothing with nano coating to protect from stains. http://www.spice.centers.ufl.edu/Modules.html Nano -based Product DIRT REPELLING CLOTH USING NANO SUPERHYDROPHOBIC COATING Nanotechnology brings super hydrophobicity 30  Wouldn‘t it be Nice if…? …more materials could be self-cleaning? water repellant? Can you think of some?  Namib beetle to nanotube forests Carbon nanotube forests Researchers from Rice University modified carbon nanotube forests grown through a process created at Rice, giving the nanotubes superhydrophobic (water-repelling) bottom and a hydrophilic (water loving) top. The forest attracts water molecules from the air and, because the sides are naturally Living in the desert the thirsty hydrophobic, traps them inside. Namib beetle collects dew to It doesn‘t require any external energy, and it drink using nanodots on its keeps water inside the forest. ―You can back. squeeze the forest to take the water out and use the material again.‖ http://news.rice.edu/2014/06/11/nanotube-forests-drink-water-from-arid-air/ Namib beetle to dew bank bottle http://www.yankodesign.com/2010/07/05/beetle-juice-inspired/ https://www.fastcoexist.com/3057197/this-nano-material-sucks-water-from-thin-air 33  Toucan beaks Toucans have very large beaks for the size of their bodies. The structure at the nano level makes Toucan Beaks incredibly light and strong. – Engineers and Scientists developing similar structures to make stronger, lighter materials. http://www.spice.centers.ufl.edu/Modules.html  Toucan Beaks The nanostructure of toucan beaks inspires automotive panels that could protect passengers in crashes. And inspires construction of ultralight aircraft components. http://pubs.acs.org/cen/critter/critterchemistry.html  Woodpeckers Beaks mimics as a shock absorber woodpecker makes a blow into the tree trunk, its beak repeatedly strikes at a speed of 6–7 m/s, and the impact deceleration is of the order of 1000 g. The physical characteristics of the head include spongy bone on the upper beak, an extended hyoid bone, a tightly enclosed small brain within the skull and a plate-like high-strength cranial bone. http://www.picgifs.com/bird-graphics/bird-graphics/woodpecker/bird-graphics-woodpecker-516264.gif 36 Why woodpecker beaks? The dimensions and aspect ratios of the height over the width of a keratin scale from each bird are different according to their functions. The inner layers of the beaks show various porosities according to their function. 37  Why we study about Woodpeckers beak ? Gives clue to solve human engineering problems related to energy absorption and shock mitigation Woodpecker beak Human engineering 38  Where we use this biomimicry? Specific biomimetic applications include employment of spiral and wavy structures found in nature and possibly using the woodpecker ‗s geometrical advantages in car bumpers and Athletics Helmets. 1. Car bumpers 2.Athletics helmets 39  It applies gentle compression to the jugular veins ,slightly reducing the amount of blood flowing back to the heart after every beat http://rsif.royalsocietypublishing.org/content/11/96/20140274.article-info 40  Shark Skin Ever wonder how sharks swim so fast? The various size/shapes and texture of shark skin at the micro and nano levels reduce drag and make sharks very fast in the water. – This idea has been used to create reduced drag suits for athletes. http://www.spice.centers.ufl.edu/Modules.html Nanomachine from flagella 10 nm dia. x 10,000 nm long helix 20,000 rpm; reverses within 1 msec 10-16 watts proton motive force 42  Summary Biomimicry: Gecko, moth eyes, butterfly, peacock, lotus leaf, toucan beaks etc.. Nanosciences uses biomimicry. 43