Symposium O
Mining Smartness From Nature. From Bio-inspired Materials to Bionic Systems

Session O-1 - Algorithms, Mechanisms and Structures in Nature as Inspiration for Mimicking

O-1:IL01  Biomimetic Art
F. SCHENK, Birmingham City University, Birmingham, West Midlands, UK

Parallels are being drawn between the pursuit of mimesis in art and that of biomimetics in the sciences. In line with Aristotle’s definition of mimesis as ‘imitation of nature’ both via form and material, the emphasis here is on biomimetic materials - in particular novel color-shift technology and it’s potential to simulate the full spectrum of nature’s colours. Colour as dynamic and dazzling as the iridescent hues on the wings of certain butterflies has never been encountered in the art world. Unlike and unmatched by the chemical pigments of the artists’ palette, this changeable colour is created by transparent, colourless nanostructures that, as with prisms, render spectral colour visible. Until now, iridescent hues, by their very nature, have defied artists’ best efforts. However, via scientific study of the ingenious ways in which such displays are generated in nature, the artist and researcher Franziska Schenk eventually arrived at vital clues on how to adapt and adopt these challenging optical nano-materials for painting. And indeed, after years of meticulous and painstaking research both in the lab and studio, the desired effect is achieved. The resulting paintings, like iridescent creatures, do fluctuate in perceived color - depending on the light and viewing angle. In tracing the artist’s respective biomimetic approach, the paper not only provides an insight into the new colour technology’s evolution and innovative artistic possibilities, but also suggests what artists can still learn from nature.


O-1:IL02  Order and Disorder in Natural Photonic Systems
B. WILTS, Adolphe Merkle Institute, Fribourg, Switzerland

The striking appearance of many animals is not obtained by pigments but rather by structuring transparent materials on the order of a few hundreds of nanometers [1]. The biological world has optimized such photonic structures in fish scales, bird feathers and insect wings [2-5], since the Cambrian explosion over 500 million years ago, with which an enormous diversification of insect coloration as well as visual systems started. By changing the dimensions of such nanostructures or the amount of order, quasi-order or disorder in these systems, these diverse nanostructures allow manipulation of incident electromagnetic radiation so to achieve colors that extend over the entire visible wavelength range and that have a strong biological significance. In this talk I will present the optical properties of different topologies of biological photonic structures, from ordered and quasi-ordered to disordered ones. I will discuss how such structures and topologies can be optically understood and serve as an inspiration to find novel optical materials, e.g. metamaterials [2].
[1] Kinoshita (2008),[2] Dolan et al. (2015) Adv. Opt. Mater. 3, 12. [3] Saranathan et al. (2015) Nano. Lett.15, 3735. [4] Wilts et al. (2014) PNAS 111, 4363. [5] Burresi et al. (2014) Sci. Rep, 4, 6075.


O-1:IL03  Tuning Mechanical Properties of Spider Cuticle by its Composition and by Structural Gradients
Y. POLITI¹, B. BAR-ON¹, F.G. BARTH², P. FRATZL¹, ¹Department of Biomaterial, Max-Planck-Institute of Colloids and Interfaces, Potsdam, Germany; ²Department of Neurobiology, Faculty of Life Sciences, University of Vienna, Vienna, Austria

The cuticular exoskeleton of arthropods not only serves the support and protection of the animal but also comprises a variety of tools and sensors. Although built of the same building blocks as the rest of the cuticle these tools and sensory organs often show specific multiscale architectural and compositional gradients. These in turn govern the local materials´ properties, supporting the adaptation of these structures to their specific biological functions. Among the different cuticular structures of the spider Cupiennius salei we study the tarsal tendon, the cheliceral fangs, tarsal claws and the mechanosensitive slit sensilla, in order to better understand how cuticle composition and structural properties contribute to specific functions. We use a variety of structural and spectroscopic methods and correlate our findings with local mechanical properties of the material. Further insight is gained by employing a multi-scale structural modelling approach using Finite Element Analysis (FEA) and analytical calculations. The experimental as well as the modelling methods and physical insights of the work presented are potentially important for investigating and understanding the architecture and structural motifs of other cuticular tools and biological sensors. They may also help to elucidate principles aiding the design of bio-inspired new materials, embedded sensors and various technical tools. 
 

O-1:L04  Introducing Self-healing in a Lattice Spring Model to simulate Bone Fracture and Repair
F. BOSIA¹, L. BRELY¹, N.M. PUGNO^2,3,4, ¹Department of Physics, University of Torino, Torino, Italy; ²Laboratory of Bio-Inspired & Graphene Nanomechanics, Department of Civil, Environmental and Mechanical Engineering, University of Trento, Trento, Italy; ³Center for Materials and Microsystems, Fondazione Bruno Kessler, Povo (Trento), Italy; ⁴School of Engineering and Materials Science, Queen Mary University of London, London, UK

Artificial self-healing materials draw inspiration from the unique properties of biological structural materials that are able to regenerate and repair themselves when damage occurs. A great number of parameters contribute in determining overall material mechanical behaviour, including constituents types, volume ratios, micro- and macro-structure, hierarchical architecture, healing rate, healing location(s) and related mechanisms. Here, we present a lattice spring model approach to simulate the behaviour of these self-healing composite materials. Growth and degradation evolution laws are also introduced in the model for the time evolution of mechanical properties of the different phases in the composite, including the influence of external loading. The model is used to simulate the fracture and healing behaviour of biologic materials such as bone and to evaluate the performance of potential next generation self-healing materials. The proposed model can thus help guide in the choice of material combinations, structural arrangements and mechanical treatments in experimental configurations.


Session O-2 -  Bio-inspired and Bio-enabled Materials and Manufacturing

O-2:IL01  Bio-enabled, Chemically-tailored, Hierarchically-structured, 3-D Materials
K.H. SANDHAGE, School of Materials Engineering, Purdue University, West Lafayette, IN, USA

Impressive examples can be found throughout nature of the biological assembly of intricate hierarchically-patterned, rigid 3-D structures. While the morphological complexity and diversity of such self-assembled biogenic structures is breathtaking, the range of chemistries (particularly inorganic chemistries) possessed by such structures pales in comparison to the rich variety of synthetically-derived materials. Although valiant attempts have been made to induce organisms to assemble 3-D structures comprised of new, non-naturally-occurring inorganic materials, such efforts have met with quite limited success. An alternative strategy is to use synthetic chemical approaches to alter the chemistry, but not the morphology, of biogenic or biomimetic structures. In this presentation, two general strategies for the chemical conversion of microscale/nanostructured biogenic and biomimetic/synthetic assemblies into replicas comprised of new functional inorganic materials will be discussed: i) shape-preserving gas/solid reactions (for the transformation of inorganic structures), and ii) highly-conformal coating methods (for inorganic or organic structures). Such chemically-tailored, 3-D structures can be attractive for a variety of catalytic, optical, sensor, energy, and other applications.


O-2:IL02  Novel Bio-inspired Morphing Materials
G. LANZARA, K SAMADIKHAH, E. BARRESI, Y. CHEN, Engineering Department, University of Rome, RomaTre, Italy

Blood vessels represent a great inspiration for the realization of novel materials with local and global morphing capabilities. Vessel's local volume and blood pressure are controlled by vascular smooth muscle cells, hosted in the multilayered vessel's wall, which make the vessel change shape locally. When the body is excessively warm/cold, the blood vessels that are closer to the skin, automatically dilate/constrict so as to enhance/reduce heat exchange with the external environment. These morphing phenomena occur keeping constant the overall vessel length, in contrast with the behavior of known materials. Here, novel passive and self-adaptive lightweight materials and related manufacturing methods are presented taking inspiration from the above blood vessels functionalities. The local morphing capability, in response to a mechanical stimuli, is achieved by designing a novel miniaturized auxetic structure, while the self-adaptive functionality in response to a thermal stimuli, is achieved with a unique material design in which morphing is automatically activated by temperature. The latter exploits a purely thermo-mechanical approach in distributed nano-scaled mechanisms. A novel low-cost, nano-scaled manufacturing method to fabricate the above materials, will also be presented


O-2:IL03  UV-absorbing Materials based on Natural Marine Sunscreens and Biopolymers
S.C.M. FERNANDES¹, V. BULONE^1,2, ¹Division of Glycoscience, School of Biotechnology, Royal Institute of Technology (KTH), AlbaNova University Center, Stockholm, Sweden; ²ARC Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, South Australia, Australia

To prevent the negative effects of ultraviolet (UV) radiations from sunlight (e.g. skin cancer), we have designed and prepared novel UV-absorbing materials inspired by nature and entirely based on marine organisms. The unique physicochemical and structural properties of biopolymers were combined with the remarkable UV-absorbing capacity of metabolites designated as mycosporine-like amino acids (MAAs). MAAs are known to act as natural sunscreens in marine organisms, namely cyanobacteria, algae, fungi and some fish species. Chitosan was used as a matrix to graft or entrap the MAAs. The resulting UV-absorbing materials retained the characteristic absorption peaks of the MAAs in the UVA and UVB regions, and exhibited a strong capacity to absorb both types of UV radiations. The materials were also photostable and thermoresistant after exposure to drastic physical treatments. The biocompatibility of the materials was assessed using cell cultures of murine fibroblasts. The materials were shown to be non-cytotoxic and fully compatible with cell proliferation and adhesion. Thus, they present a high potential for use in medical devices and many other applications.


O-2:L04  Transport and Mechanical Properties of Ordered Biomimetic Porous Materials from Freeze Casting and Ionotropic Gelation
M. KEUPER, K. KLANG, G. BUCK, C. LAUER, K.G. NICKEL, University Tuebingen, Applied Mineralogy, Tuebingen, Germany

The combination of freeze casting and ionotropic gelation enables the manufacture of a variety of ordered porous inorganic materials. Both methods use self-organizing mechanisms, where the filler substance of a colloidal suspension is placed in regular spaced channels during the process. The combination of those methods allow extremely high porosities. Using Alumina as a model ceramic we demonstrate the variability in terms of channel sizes, channel diameter distributions and wall geometry. Such materials combine transport properties with high energy dissipation during compressive failure, which is akin to natural skeleton materials from sea urchin spines or plants. We will show our first results on the correlation of microstructural parameters with mechanical properties and permeabilities. Furthermore we discuss the possibilities of creating composites from such materials, which potentially add further properties like high damping qualities to these multifunctional biomimetic constructions.


O-2:L05  Textile as Artificial Nature - From Synthetic Sea Grass to Fibrous Implants
N.-K. PERSSON, Smart Textiles Technology Lab, Swedish School of Textiles, University of Borås, Borås, Sweden

We develop the hypothesis that textiles and nature have much in common and that in a time of biomimetics textile is a unique class of material that provides a bridge between artefacts, by definition synthetic, and biofacts - material entities found in and produced by nature, i.e. non-synthetic. Some characteristics of natural biofact materials and structures include pliability, softness, porosity, light weight, recyclability, and periodicity. Textiles are soft, foldable, of low weight, inherently porous, anisotropic as well as periodic, easily compatible with biodegradability and recyclability. Thus there are many similarities. These are discussed together with a number of cases where textiles are mimicking biofacts in a context of ecosystem service. We first look at synthetic see grass (Zostera marina) for remediation of one of the most important biotopes in the world where we show that textile processing techniques are able to make production efficient. One of the most valuable ecosystem services is the provision of clean water. Textile based water purification systems has been constructed and merged with fungus (Zygomycetes) we show the potential for enhancing wet land capability. Finally, we show textile is a material for actuating implants mimicking human tissue.


O-2:L06  Multidimensional Biomimetic Synthesis of Magnetic Materials via Selective Mineralization of Ferritin Subunits
D. CARMONA¹, L. TRECCANI², S. LID³, L. COLOMBI CIACCHI^3,4, ¹Advanced Ceramics, Faculty of Production Engineering, University of Bremen, Germany; ²Petroceramics Spa, Kilometro Rosso Parco Scientifico Tecnologico, Stezzano, Bergamo, Italy; ³Hybrid Materials Interfaces, Faculty of Production Engineering, University of Bremen, Germany; ⁴MAPEX Center for Materials and Processes, University of Bremen, Germany

Due to its biomineralizing ability the cage-shaped protein Ferritin (FN) is widely used as size-restricted reaction vessel for the synthesis of engineered nanomaterial. FN forms ferrihydrite nanoparticles in the protein cavity via a multi-step reaction. In FN mineralization is controlled by two protein subunits with complementary functions: the H chain contains the catalytic sites for Fe(II) oxidation and the L chain enhances the stability of the ferrihydrite core. Here we show for the first time that even disassembled, individual H and L chains can selectively induce iron oxide and Co-doped-iron oxide mineralization. By combining experimental and atomistic modelling the binding and mineralization behaviour of single H and L chains immobilized on silica and alumina surfaces is deciphered. Individual FN subunits immobilized on different metal oxide materials (nanoparticle, porous beads and 3D cellular scaffolds) enable the formation of homogenous, continuous magnetic films with controllable size, shape and magnetic behaviour. This approach opens infinite possibilities for the fabrication of biomimetic functional material with tunable properties and of relevance for a broad range of applications e.g. magnetic devices, biomedical sensors, drug carriers, catalytic and memory devices.

 
Session O-3 - Functional Bio-inspired Surfaces and Interfaces

O-3:IL01  Nanostructuring Surfaces to Control Wetting
F. SCHELLENBERGER, S. WOOH, N. ENCINAS, P. PAPADOPOULOS, D. VOLLMER, H.-J. BUTT, Max Planck Institute for Polymer Research, Mainz, Germany

Super liquid-repellency can be achieved by nano- and microstructuring a low energy surface in such a way, that protrusions entrap air under¬neath the liquid. To better understand how a drop advances and recedes on such a structured surface, we imaged the motion of a water drop on a superhydrophobic array of micropillars by laser scanning confocal microscopy. Commonly, super liquid-repellency is defined by a high apparent advancing contact angle and a low roll-off angle for a liquid droplet. These microscopic videos demonstrate that to define super liquid-repellency the apparent receding contact angle should be high. In addition, a high impalement pressure is required. By calculations we demonstrate that to achieve both, the features constituting the layer should be as small as possible. In addition, applications of super liquid-repellent surfaces are discussed, e.g. for fabricating micro¬spherical supraparticles or as coating for gas exchange membranes.


O-3:L02  S-layer Lattices as Templates for Molecular Imprinting
D. PUM, E. LADENHAUF, D.S. WASTL, U.B. SLEYTR, University of Natural Resources and Life Sciences, Vienna, Austria; P.A. LIEBERZEIT, University of Vienna, Vienna, Austria

Crystalline bacterial cell surface layer (S-layer) proteins are one of the most abundant biopolymers on earth and form the outermost cell envelope component in a broad range of bacteria and archaea. S-layer lattices are highly porous protein mesh works with unit cell sizes in the range of 3 to 30 nm. One of the key features of S-layer proteins is their natural capability to form self-assembled mono- or double layers in suspension, at solid supports, the air-water interface, planar lipid films, liposomes, nanocapsules, and nano particles. Currently we are working on the fabrication of so called molecularly imprinted thin films by using reassembled functional S-layer protein arrays as stamps [1]. After polymerization of the imprint and removal of the S-layer matrix, a chemically and sterically precisely defined surface, which is complementary to the chosen template, is obtained. The unique feature of these imprints is the precisely controlled repetition of surface functional groups and topographical features – induced by the crystalline character of the S-layer protein lattice ! Characterization of the imprints by QCM and AFM demonstrated proof-of-concept and outstanding sensitivity and selectivity as sensing layers.
[1] Ladenhauf et al., RSC Advances 2015 (DOI:10.1039/C5RA14971A


O-3:L03  Cell-inspired Mechanoresponsive Interfaces
M. TIMMERMANN, S.B. GUTEKUNST, C. SELHUBER-UNKEL, Dept. Biocompatible Nanomaterials, University of Kiel, Germany

The adhesion of a cell to its environment mediates the structural organization of the cell itself and is also related to the ability of cells to mechanically adapt to environmental changes. We aim to mimic the underlying mechanisms by which cells sense, transmit, and generate mechanical forces, and particularly how cells themselves mechanically adapt to forces exerted by their environment. This mechanism relies on biopolymer fibers, as cells align and cross-link actin fibers upon external stress and connect them to adhesion clusters in a reversible process. Therefore, we build up cell-inspired, adaptive materials from functionalized micropolymer structures. We integrate the mechanism of cellular fiber cross-linking into our interfaces by choosing a polymer functionalization system that can be interconnected by cross-linkers of defined size by molecular recognition. If stress is released in the material, cross-linker binding will be broken up and the original situation is restored. Such cell-inspired intelligent materials with directional and temporal control of integrated mechanoresponsivity are paving the way towards a completely new class of self-responsive materials.


O-3:L04  Bio-inspired Multifunctional Wrinkle Surface
HIROSHI ENDO, Department of Mechanical Systems Engineering, Toyama Prefectural University, Imizu, Japan

Surface wrinkling is an inventive and unconventional technique that is also fast and inexpensive for various types of surface patterning involving sinusoids (ripples), herringbones, labyrinthine designs, etc. It is especially suited for large-area surfaces of poly(dimethylsiloxane) (PDMS) elastomers based on mechanical (buckling) instability. This self-organization buckling phenomenon is widely observed in natural systems such as humanskin, brain cortex, fruits, and plants. Owing to the periodic structure and dynamically tunable wrinkles, it has been used in many applications. In this study, we succeeded in the fabrication of a large-area ultra-water-repellent film on which water drops can be flexibly controlled by utilizing the microfabrication technique inspired by the wrinkle formation processes of living organisms. Moreover, we succeeded fabrication of film with highly adhesive superhydrophobic surface and SERS activity.


O-3:IL05  Biomimetic Design and Manufacturing of Anti-erosion Functional Surfaces Inspired from Desert Scorpion
ZHIWU HAN, Key Laboratory of Bionics Engineering of Ministry of Education, Jilin University, Changchun, China

Sand erosion is a phenomenon where solid particles impinging to a wall cause serious mechanical damages to the wall surface. It’s tough to be a machine in the desert: particles of sand work their way into moving parts, where they abrade helicopter propellers, airplane rotor blades, pipes and other equipments. However, the desert organisms live their entire lives subjected to blowing sand, yet they never appear to erode. In this study, the anti–erosion characteristic mechanism of the scorpion surfaces under the dynamics effect of gas / solid mixed media was studied. Biomimetic embossed surfaces consisting of an array of three types grooves are designed to quantify their erosion wear resistance properties. A smooth surface sample was fabricated for comparison. The results show that the anti-erosion property of biomimetic samples can be attributed to the rotating flow in the grooves that reduces the particle impact speed. Besides, the simulation and experiment of the erosion wear behavior show that the biomimetic surface for centrifugal fan blades with optimum parameters could effectively improve anti-erosion property by 28.97%. We envision that more opportunities for biomimetic application in improving the anti–erosion performance of parts that work under dirt particle environment.


O-3:L06  Nature-inspired Polymeric Nanofur for Environmental Applications: from Oil Spill Cleaning to Frictional Drag Reduction
M. KAVALENKA, C. ZEIGER, F. VÜLLERS, J. KUMBERG, H. HÖLSCHER, Institute of Microstructure Technology, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany

Developing novel methods for cleaning oil spills and reducing energy losses related to frictional drag has attracted global research efforts. Inspired by water ferns, water bugs and fish scales, we developed a hair-covered nanofur material, whose properties can be tailored to satisfy specific requirements in oil/water separation and drag reduction applications. The superhydrophobic nanofur is fabricated by structuring conventional and biodegradable polymers using a hot pulling method. The as-prepared superhydrophobic nanofur absorbs crude oil out of water and separates oil/water mixtures [1]. The nanofur surface can be changed to underwater superoleophobic, making it capable of removing water from mixtures. Microporous nanofur filters allow continuous removal of water or oil from oil/water mixtures. Furthermore, bioinspired nanofur possesses an air-retaining property necessary for reducing frictional drag. The air film retained by the nanofur underwater is highly stable under applied hydraulic pressure. The measured pressure drop across microfluidic channels lined with nanofur is ~50% lower than in unstructured channels, indicating a significant drag reduction [2].
[1] Röhrig et al. Adv. Mat. Interfaces, 1(4) 2014 [2] Kavalenka et al. ACS Appl. Mater. Interfaces, 7 (20) 2015


O-3:L07  Spinach Extracts for the Development of Metal Patterns onto Plastic Substrates
D.E. WATSON, J. MARQUES-HUESO, M.P.Y. DESMULLIEZ, Heriot-Watt University, School of Engineering & Physical Sciences (EPS), Institute of Signals, Sensors and Systems, Microsystems Engineering Centre (MISEC), Edinburgh, Scotland, UK

Flexible circuits and interconnections are ubiquitous in modern electronics devices. This article introduces an uncomplicated, low-cost method for direct metallisation of common polymer substrates using spinach extract as a photocatalyst. The polymer is doped with silver ions, which will reduce to silver nanoparticles when exposed to a UV light source and in the presence of a suitable source electron donor source. Although a laser can be used as the light source to provide very high speed patterning at the resolution of a few microns, its energy can cause unwanted substrate interactions. This problem can be overcome however. By appropriating the proteins involved in energy transfer during photosynthesis as the electron donor source, the time taken for formation of silver nanoparticles on the substrate has been considerably reduced. The quicker silver formation means our re-imagining of photosynthesis in this manner has also greatly decreased the incident energy, thus decreasing the chance of substrate degradation. Silver tracks have been formed with a linewidth of less than 50 µm.


O-3:L08  Bioinspired Multi-gradient Surfaces with Water Collection/Repellency
YONGMEI ZHENG, School of Chemistry and Environment, Beihang University, Beijing, China

Biological surfaces endow the gradient features of micro- and nanostructures to control wettability. Spider silk hangs large pearly droplets and displays the ability of water collection, as result of wet-rebuilt structures to generate both surface energy gradient and difference of Laplace pressure, where the cooperation of gradients drives the tiny droplets to gather water. Series of bioinspired silks have been fabricated at micro- and nano-level to achieve functions such as  capturing of droplets; as-selected directional driving of tiny condensed droplets, long range transport of droplet, and humidity/temperature/photo response. Other gradients of surfaces are designed, e.g., high adhesive surface with chemical rough gradient for droplet spreading in directions; star-shape wettable pattern for the efficiency of water collection; super-hydrophilic oriented nano-hairs array for directional water repellency at high temperature; micro- and nanostructured arrays for anti-icing/ice-phobicity; and nano-fibers array with chemistry gradient for anisotropic spreading, and so on. These studies are helpful to design novel surfaces that can be extended into applications, e.g., micro-fluidics, micro-devices or reactors, etc.


Session O-4 -  Bio-inspired Sensors and Actuators

O-4:IL01  Recent Developments in Bio-inspired Sensors Fabricated by Additive Manufacturing Technologies
G. KRIJNEN, R. SANDERS, Transducers Science & Technology Group, University of Twente, Enschede, The Netherlands

In our work on micro-fabricated artificial hair-sensors, inspired by the flow-sensitive sensors found on crickets, we have made great progress. Initially delivering mediocre performance compared to their natural counter parts they have evolved into capable sensors with thresholds roughly a factor of 30 larger than of their natural equivalents. Due to this disparity, and also instigated by our work on fly-halteres inspired rotation rate sensors and desert locust ear-drum mimicking membrane structures, we have analyzed the difference between natural and man-made sensors. We conclude that two major drawbacks of main-stream micro-fabrication are the lack of easily applicable soft materials, as well as the limitations imposed by photolithography based fabrication with respect to freeform 3D shaping of structures. Since then we have targeted additive manufacturing for sensor structures. Rotation rate sensors based on the mammalian vestibular system, as well as thin membranes for acoustic sensing and mechanical filtering, were investigated. In this contribution we will present the analysis of existing micro-fabricated bio-inspired sensors and report initial results of sensor structures fabricated by additive manufacturing.


O-4:IL02  Nature-inspired DNA-based Sensors
F. RICCI, University of Rome, Tor Vergata, Rome, Italy

Here I report novel nature-inspired approaches for the development of DNA-based switches for the detection of clinically relevant protein targets. The inspiration behind these approaches is derived from nature’s sensing systems, which employ nanometer-scale protein and nucleic-acid-based “switches” to detect thousands of distinct molecules (including disease markers) in real time within complex physiological environments. In the first strategy I will show the possibility to exploit the “designability” of DNA to fabricate molecular nanoswitches that support the one-step fluorescent and electrochemical detection of specific antibodies. In the second strategy I will show the development of DNA-based electrochemical and optical switches for the quantitative, single-step detection of specific transcription factors. Using these sensors we demonstrated the rapid, quantitative detection of physiologically relevant, low-nanomolar concentrations of clinically relevant protein targets directly in complex clinical samples.


O-4:IL03  Micromechanics of Vibration Sensors in the Spider Cuticle
V.V. TSUKRUK, School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA, USA

I discuss recent results from our research group on characterization of mechanotransducing sensory systems in wandering spiders as represented by arrays of air-flow sensitive hairs and slits with dendritic nerve cells which can serve as bioinspired sensor structures.[i]  Highly sensitive lyriform organs located on the legs of the wandering spider Cupiennius salei allow the spider to detect nanometer-scale strains in the exoskeleton resulting from locomotion or substrate vibrations.  Morphological features of the lyriform organs result in their specialization and selective sensitivity to specific mechanical stimuli, which makes them an effecient functionalized bioinspired strain sensors.  Here we utilize atomic force microscopy force spectroscopy to probe the nano-scale mechanical properties of spider hairs [ii], soft pads [iii],[iv], and two slit-like lyriform organs.[v] Force distance curves obtained from AFM measurements displayed characteristic multi-layer structure behavior, with calculated elastic moduli ranging from 150 MPa to 500 MPa for different regions and indentation depths.  Extremely sensitive time-dependent behavior was directly measured for hairs on live spiders at different frequencies.  Time-dependent behavior for slits indicates the viscoelastic nature of the sensor-biomaterials with mechanical relaxation times potentially playing a role in the neural adaptation behavior of the lyriform organs.
[i] M. E. McConney, K. D. Anderson, L. L. Brott, R. R. Naik, V. V. Tsukruk,, Bioinspired Material Approaches to Sensing, Adv. Funct. Mater., 2009, 19, 2527. [ii] M. E. McConney, C. F. Schaber, M. D. Julian, W. C. Eberhardt, J.A.C. Humphrey, F. G. Barth, V. V. Tsukruk, Surface force spectroscopic point load measurements and viscoelastic modelling of the micromechanical properties of air flow sensitive hairs of a spider (Cupiennius salei), JRS Interface, 2009, 6, 681-694. [iii] M. E. McConney, C. F. Schaber, M. D. Julian, F. G. Barth, V. V. Tsukruk, Viscoelastic nanoscale properties of cuticle contribute to the high-pass properties of spider vibration receptor (Cupiennius salei Keys), Interface, 2007, 4, 1135. [iv] M. Erko, O. Younus-Metzler, A. Rack, P. Zaslansky, S. L. Young, G. Milliron, M. Chyasnavichyus, F. G. Barth, P. Fratzl, V. Tsukruk, I. Zlotnikov, Y. Politi,,Micro- and nanostructural details of a spider’s filter for substrate vibration: relevance for low-frequency signal transmission. Interface, 2015, 12, 20141111. [v] S. L. Young , M. Chyasnavichyus, M. Erko, F. G. Barth, P. Fratzl, I. Zlotnikov, Y. Politi, V. V. Tsukruk, A spider’s biological vibration filter: micromechanical characteristics of a biomaterial surface, Acta Biomat., 2014, 10, 4832-4842.
 

O-4:L04  A Bio-inspired Real-time Capable Artificial Lateral Line System for Freestream Flow Velocity Measurements
C. ABELS^1,2,3, W.M. MEGILL¹, A. QUALTIERI², M. DE VITTORIO^2,3, F. RIZZI², ¹Rhine-Waal University of Applied Sciences, Faculty of Technology and Bionics, Kleve, Germany; ²Center for Biomolecular Nanotechnologies @UNILE, Istituto Italiano di Tecnologia, Arnesano (LE), Italy; ³Università del Salento, Dip. di Ingegneria dell’Innovazione, Lecce, Italy

To enhance today’s artificial flow sensing capabilities in aerial and underwater robotics, future robots will have to be equipped with a large number of miniaturised sensors distributed over the surface to provide high resolution measurement of the surrounding fluid flow. In this work we show a linear array of bio-inspired microelectromechanical flow sensors whose sensing mechanism is based on a piezoresistive strain-gauge along a stress-driven cantilever beam, bio-mimicking the biological superficial neuromasts found in the lateral line organ of fishes. This array of closely separated artificial hair cell sensors is able to calculate orientation and velocity information to be used as input for the vehicle’s control procedure. A real-time capable cross-correlation procedure is presented which allows to extract information from flow velocity fluctuations, providing a robust measurement system that is also capable of measuring events in turbulent flows. The data gathered in the work revealed a systematic correlation between measurement accuracy, sensor distance in the array arrangement, and sampling frequency of the data acquisition hardware. The computed flow velocities deviate from a commercial system by 0.09 m/s and 0.15 m/s at 0.5 m/s and 1.0 m/s flow velocity, respectively.


 
Session O-5 -  Biologically Inspired Systems and Robotics

O-5:IL01  Bioinspired Micro- and Nanoswimmers
P. FISCHER, Max Planck Institute for Intelligent Systems, Stuttgart, and Institute of Physical Chemistry, Univ. of Stuttgart, Germany

At low Reynolds number (Re << 1) simple reciprocal shape changes do not result in any net displacement of a swimmer in water. This limitation is known as the “scallop theorem”. Hence, asymmetric non-reciprocating complex actuation mechanisms are required for swimming. With this complication in mind, I will discuss experimental systems that we have developed that overcome kinematic reversibility and are effective in their locomotion at small scales. I will discuss nanopropellers that are so small that they can move through the macromolecular network of biological tissue-like gels. An example of a flagellar-like structure that mimics a bacterial cell to move through mucus is also presented. I will show that the complex hydrodynamics of non-Newtonian fluids presents an engineering opportunity as it allows symmetric microswimmers to be built and actuated - swimmers that cannot move in water because of the “scallop theorem”. Finally, I will show how one may encode complex actuation schemes in polymeric swimmers made from photoactive macromolecules.


O-5:IL02  Biologically Inspired Robots
P. MANOONPONG, The Maersk Mc-Kinney Moller Institute, Odense, Denmark

Walking animals, like insects, with little computing can effectively perform complex behaviors. For example, they can walk around their environment, escape from corners/deadlocks, and avoid or climb over obstacles. While performing all these behaviors, they can also adapt their movements to deal with an unknown situation or terrain change. As a consequence, they successfully navigate through their complex environment. Biological studies suggest that these achievements are the result of an integration of several ingredients embedded in their sensorimotor loop. The ingredients include biomechanics (i.e., morphology, muscles, and materials), sensory feedback, and neural mechanisms. In this lecture, I will present how we use biological systems as inspiration to develop multi sensori-motor robotic systems (i.e., biologically inspired walking robots). The bio-inspired approach allows the robots effectively interact with the environment and perform complex behaviors. The behaviors include adaptive locomotion on difficult terrains, a multitude of different walking patterns, proactive behavior, memory-guided behavior, and goal-directed behavior.


O-5:IL03  Biological Fundaments on Biomimetics of Gecko Locomotion
ZHENDONG DAI, Institute of Bio-inspired Structure and Surface Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, China

The paper systematically reviews the biological studies related to the biomimetics of gecko locomotion from structure, material, adhesive mechanism and locomotion behaviors and reaction forces. The detail structures and their functions of setae, flaps, toes, legs and spine are discussed. The composition of biological materials, esp. adhesive setae, is reviewed. The contribution of charged proteins in setae to the adhesion is especially paid attentions. The various adhesive mechanisms are discussed and the bionic principles based on the mechanisms are set up. The motion behaviors, reaction forces and the relationship to the degree of inclined substrate are discovered. How to receive reliable attachment and to obtain coordination among over-driven legs is reviewed. The paper will set up biological fundaments on biomimetics of gecko locomotion.


O-5:IL04  Three-dimensional Needle Steering for Neurosurgery - A Biologically Inspired Approach
R. SECOLI, F.M. RODRIGUEZ Y BAENA, Dept. Mechanical Eng., Imperial College London, London, UK

Surgical robotics is gaining in popularity due to the ever-increasing need for more complex, accurate, but less invasive surgery, which conventional instruments are holding back. Amongst the many embodiments at different stages of research and development, needle steering holds promise, but has yet to demonstrate real clinical impact. This minimally invasive procedure involves the insertion of a thin, flexible needle through the skin and into tissue, for application to a variety of clinical needs, including diagnostics, therapy and therapy monitoring. The ability to steer the needle enables the surgeon to avoid obstacles and counteract targeting inaccuracies due to tissue deformation (due to tool-tissue interactions) and organ motion (due to e.g. breathing and pulsatile forces), but these first need to be appropriately modelled and tracked, which remains an open challenge. This talk will provide an overview of exciting new research on a steerable needle, code-named STING, which is inspired by the ovipositor (or egg laying channel) of parasitic wasps, and demonstrates unmatched dexterity and intrusiveness. The team’s work to date on manufacture, imaging, and control will be outlined, followed by some general conclusions about current challenges and future opportunities.


O-5:L05  Auto-Gopher II – Wireline Deep Sampler driven by Percussive Piezoelectric Actuator and Rotary EM Motors
Y. BAR-COHEN¹, K. ZACNY², M. BADESCU¹, H.J. LEE¹, S. SHERRIT¹, X. BAO¹, G.L PAULSEN², L. BEEGLE¹, ¹Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA; ²Honeybee Robotics Spacecraft Mechanisms Corporation, Pasadena, CA, USA

Two of the key objectives of future NASA’s solar system exploration of planetary bodies is the search for potentially preserved bio-signatures and habitable regions. To address these objectives, a biologically inspired wireline deep rotary-percussive corer, called Auto-Gopher, has been developed. The corer employs a piezoelectric actuated percussive mechanism for breaking formations and an electric motor rotates the bit to remove the powdered cuttings. The first generation implementation of the lesson to deep drilling has been focused on the demonstration of the capability. In a field test, 3-meter deep drilling in gypsum was accomplished while using a separate mechanism to break the formed cores and remove them. The average drilling power consumption was in the range of 100-150 Watt, while the rate of penetration was approximately 2.4 m/hr. Currently under development is the second generation, fully autonomous drill that is called the Auto-Gopher-II, which performs coring, core break-off and retrieval. In this paper, the capabilities that are being integrated into the Auto-Gopher-II will be presented focusing on its mechanism and performance.


O-5:L06  A Climbing Robots based Claws Interlocking with Flexible Material
AIHONG JI, ZHIHUI ZHAO, NAN JIANG, ZHENDONG DAI, Institute of Bio-Inspired Structure and Surface Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, China

Animals have optimized several ways to climb various substrates，by developing claws and specialized adhesive pads—smooth and hairy pads．The interaction of claws with a rough substrate depends on the mechanism of mechanical interlocking. In order to design a robot which can climb vertically on rough surfaces, a claw-inspired wall-climbing robots with flexible material was focused. The pre-tarsus’ morphology of insects were observed, and the surface roughness as well as diameters of their claw tips was measured under a microscope to account for the grasping mechanism of these insects on the sloping substrate. The results showed that the interaction of claws with substrates is determined by the roughness of the substrate, the friction coefficient and the relative dimension between claws and substrates.The stability of the interaction depends on the mechanism of mechanical interlocking. A claw-interlocking mechanism has been developed and design a gripper as an interlocking structure of a foot with flexible material which can compliant to the different rough surfaces. Then the climbing robot with four legs has been designed to verify the interlocking mechanism. The robots can climb vertically on different rough surfaces.


Session O-6 -  Bio-inspired Optics and Photonics

O-6:L02  Omnidirectional Anti-reflection Structures Inspired by the Random Nanostructures of the Glasswing Butterfly (Greta oto)
R.H. SIDDIQUE, G. GOMARD, H. HÖLSCHER, Karlsruhe Institute of Technology, Karlsruhe, Germany

As its name suggests, the Glasswing butterfly (Greta oto) has transparent wings with remarkable low reflectance below 5% even for large view angles [1]. This omnidirectional anti-reflection behavior is caused by nanopillars with subwavelength radii covering the transparent region of its wing membrane. In difference to the classical biological anti-reflection structures, these pillars feature a random height and width distribution. Using optical simulations we demonstrate that this randomness is responsible for the omnidirectional anti-reflection properties of the Glasswing butterfly. Especially, the random height distribution drastically reduces the reflection for large view angles of 80° enabling efficient camouflage by transparency during the flight. Based on this design principle almost perfect anti-reflection surfaces can be engineered for a broad band of wavelength and an extremely wide range of view angles. Such anti-reflective surfaces are needed for applications ranging from efficient solar cells, sensors, surface emitting lasers, LED and various opto-electronics application. Finally, we will discuss possible options to fabricate artificial replicas of these highly random nanostructures.
[1] Siddique, Gomard, Hölscher,. Nat. Commun. 6, 6909 (2015).


O-6:L03  Biological Inspiration in Optics and Photonics – Harnessing Nature’s Light Manipulation Strategies and Manufacturing Capabilities for Multifunctional Optical Materials
M. KOLLE, J. SANDT, S. NAGELBERG, A. MCDOUGAL, Mechanical Engineering Department, MIT, Cambridge, MA, USA; LING LI, J. AIZENBERG, School of Engineering and Applied Sciences, Harvard University, USA; P. VUKUSIC, College of Engineering, Mathematics and Physical Sciences, Exeter University, UK

Control of light–matter interactions is crucial for many organisms in their struggle to survive. Many species rely on a combination of optical effects arising from light scattering and absorption in sophisticated hierarchical photonic structures. Selection criteria for biological photonic structures are not unlike the requirements faced in the development of novel optical technology. For this reason, biological light manipulation strategies provide inspiration for the creation of tunable, stimuli-responsive, adaptive material platforms that will contribute to the development of multifunctional surfaces and innovative optical technology. In our research, we explore design concepts found in biological photonic architectures, seek to understand the mechanisms underlying morphogenesis of bio-optical systems, aim to devise viable manufacturing strategies that benefit from insight in biological formation processes, and ultimately strive to realize new photonic materials with tailor-made optical properties. This talk is focused on the identification of biological model photonic architectures, and a discussion of recently developed bio-inspired photonic structures, including mechano-sensitive color-tunable photonic fibers and reconfigurable fluid micro-lenses.


O-6:IL05  Morpho-colored Materials having High Reflectance in Wide Angle without Color-change: Multi-developments for Practical Applications
AKIRA SAITO, Osaka University & RIKEN (SPring-8), Osaka, Japan

Brilliant blue of some Morpho butterfly species is a typical example of the structural color and attracts interest due to a metallic luster from the biological body. However, this blue has a physically mysterious feature. The blue has high reflectance owing to interference from an ORDERED nanostructure on their scale, whereas the color does not change depending on the angle that contradicts the interference. This mystery is attributed to a specific nanostructure having nano-DISORDER to prevent the rainbow color. After successful proof of this principle by emulating the 3D nanostructures, wide potential applications of this specific structural color have been found. However, practical applications require a variety of developments such as mass-production, control of optical properties, optical simulation on the structures having the nano-disorder, fabrication of substrate-free film, powderization, etc. Especially, nano-patterned substrate with a specific nano-disorder is a key issue either for the fabrication or design, which has limited the applications. Our developments have recently overcome step by step the various difficulties, by maintaining the particular properties using simple processes, which will extend the practical applications of the specific color.


O-6:IL06  Cellulose Photonics: From Nature to Applications
S. VIGNOLINI, O. ONELLI, Department of Chemistry, University of Cambridge, Cambridge, UK

Nature’s most vivid colours are produced when light repeatedly scatters against periodically organized interfaces within nanostructured materials. One of the most striking example is the colour of Pollia fruits [1] is the results of chiral multilayered structures composed of cellulose micro-fibrils, which from a layered structures. In each component layer, cellulose micro-fibrils lie parallel to one another, with successive layers offset from each other at a small angle, so that the direction of the parallel-aligned micro-fibrils changes consistently, rotating from one layer to another and producing an intense colour-selective reflection. Biomimetic with cellulose-based architectures enables us to fabricate novel photonic structures using low cost materials in ambient conditions [2-3]. Importantly, it also allows us to understand the biological processes at work during the growth of these structures in plants. In this work the route for the fabrication of cellulose-base architecture will be presented and the optical properties of cellulose artificial structures will be analyzed and compared with natural one.
[1] S.Vignolini et. PNAS 109, 15712 (2012). [2] A. G. Dumanli et. al ACS Appl. Mater. Inter 6 (15), 12302 (2014) [3]A. G. Dumanli et. al Adv. Opt. Mat. 2, 646 (2014)


O-6:IL07  Bioinspired Materials Templates by Nature Species
DI ZHANG, JIAJUN GU, WANG ZHANG, QINGLEI LIU, SHENMING ZHU, HUILAN SU, State Key Lab of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai, China

Biological materials naturally display an astonishing variety of sophisticated nanostructures that are difficult to obtain even with the most technologically advanced synthetic methodologies. Inspired from nature materials with hierarchical structures, many functional materials are developed based on the templating synthesis method. This review will introduce the way to fabricate novel functional materials based on nature bio-structures with a great diversity of morphologies, in State Key Lab of Metal Matrix Composites, Shanghai Jiao Tong University in near five years. We focused on replicating the morphological characteristics and the functionality of a biological species (e.g. wood, agriculture castoff, butterfly wings). We change their original components into our desired materials with original morphologies faithfully kept. Properties of the obtained materials are studied in details. Based on these results, we discuss the possibility of using these materials in photonic control, solar cells, electromagnetic shielding, energy harvesting, and gas sensitive devices, et al. In addition, the fabrication method could be applied to other nature substrate template and inorganic systems that could eventually lead to the production of optical, magnetic. or electric devices or component.

 
Session O-7 - Biologically Inspired Functional/Smart Structures

O-7:IL02  Plant Inspired Smart Materials: Pomelos, Nuts and Metal Foams
C. FLECK¹,  P. SCHÜLER¹, M. THIELEN², S. FISCHER³, P. ZASLANSKY⁴, A. BÜHRIG-POLACZEK§, T. SPECK², ¹Materials Engineering, Institute of Technology Berlin, Germany; ²Botanical Garden & Plant Biomechanics Group, University of Freiburg, Germany; ³Foundry Institute, RWTH Aachen, Germany; ⁴Julius Wolff Institute, Charité Berlin, Germany

In nature, damage tolerant tissues or organs ensure survival, by failing safely. In the plant kingdom, to protect their seeds, pomelo peels have an impressive damping capacity, and Macadamia nutshells an extremely high strength. Both have a hierarchical structure, a multi-level sandwich and foam structure paired with a ball-like macro-geometry. We apply mechanical testing on different length-scales, in situ with light/electron microscopy or lab/synchrotron microtomogrpahy to characterize the structural reasons of failure resistance. The most important mechanisms identified are transferred to try and develop engineering structures based on open porous metal foams. The biomimetic foams have been produced by a modified investment casting process, and their mechanical properties under quasistatic and impact conditions are also characterised on the different length-scales of the hierarchical structures. We thus aim at developing architectured open-porous metal constructs with enhanced damage tolerance as compared to the monolithic materials, and to discriminate between the influence of material and structure.


O-7:IL05  Bio-inspired Design and Fabrication of Multifunctional Nanocomposites
QINGWEN LI, Suzhou Institute of Nanotech and Nanobionics, Suzhou, China

To design the structure for high performance and multifunctional composites, nature has offered us with rich scientific and technological clues from the formation of biological composites using common organic components via mild and green approaches. For example,super-tough spider fibers are derived from desirable orderly organization of linear protein molecules, strong hard nut skins are assembled from the mixture of cellulose and lignin molecules,and wear-resistant molluscan shells are a result of biomineralization of calcium carbonates in a brick-and-mortar manner. To make these natural composites mechanically strong, an orderly organization and a homogeneous distribution of major components such as proteins, cellulose molecules, or nanometer-sized crystals of carbonated calcium phosphates or calcium carbonates is a key structural feature. However, for synthetic functional composites, uniform dispersion and well controlled assemble of nanosized components in the second matrix are usually hard to be achieved due to severe aggregation induced by strong nanoscale interfacial interactions, especially upon a high percentage loading of nanocomposnent. Herein, we demonstrate an approach to enable the composite structure with highly aligned and unaggregated one-dimensional CNTs, by learning the formation process of biological composites. The resultant CNT composites exhibit ultra-high and stable tensile strengths up to 6.27–6.94 GPa and toughnesses up to 117–192 MPa, corresponding to the energies absorbed before rupturing of 75–124 J g-1 by considering the mass density of ~1.55 g cm-3. Such tensile strengths are more than 100% higher than those of carbon fiber/epoxy composites. We also anticipate that our processing method can be generalized for developing multifunctional and smart nanocomposites where all the surfaces of nanometer-sized components take part in shear transfer of mechanical, thermal, and electrical signals.


O-7:L06  4D Textiles inspired by Hydronastic Systems
V. KAPSALI, London College of Fashion - University of Arts London, London, UK

Botanical nastic systems demonstrate non-directional structural responses to stimuli such as pressure, light, chemicals or temperature; hygronasty refers to systems that respond specifically to moisture. Many seed dispersal mechanisms such as wheat awns, legume pods, spruce and pinecones fall within this classification. Although the variety of behaviors varies greatly from opening and closing to self-digging, the mechanism is generally based on differential hygroscopic swelling between two adjacent areas of tissue. This principle has been translated into technology using numerous methodologies from laminates to multi-material 3D printing for the creation of adaptive and self-assembling 4D systems. This paper describes the application of hygronastic principles to the design of experimental bi-component fibers and their subsequent incorporation into woven textile structures that demonstrate self-adjusting 4D behavior. Conventional textiles made from cotton, wool and rayon decrease their permeability to airflow as the microclimate moisture increases; this phenomenon is directly linked to the sensation of physiological discomfort. The resulting biomimetic textiles are able to increase their permeability to airflow in damp conditions and reduce permeability in dry by 25-30%.


Session O-8 -  Ongoing and Perspective Applications of Bio-inspired Technologies

O-8:IL01  Discovery of  New peptide Polymers that Display Aqueous Phase Behavior
A. CHILKOTI, Department of Biomedical Engineering, Duke University, Durham NC, USA

Elastin like polypeptides (ELPs) are the best studied class of peptide polymers that exhibit lower critical solution temperature (LCST) phase  behavior in water, and these polymers have  enabled innovative approaches to nanoparticle self-assembly, cancer therapy, regenerative medicine  and protein purification Despite this widespread interest, little is known about how LCST phase behavior is encoded in peptide polymers at their amino acid —primary— sequence level. To understand the sequence determinants of LCST phase behavior, I will present data that uses bioinformatics to guide the synthesis of a large family of peptide polymers that are predicted to exhibit LCST phase behavior.  Analysis of the LCST phase behavior of these polymers provides sequence heuristics to encode LCST phase behavior in intrinsically disordered peptide polymers and enables the design of polymers that encode two orthogonal functions —phase behavior and bioactivity— seamlessly at the primary sequence level.  These studies also identified polymers that display tunable degrees of thermal hysteresis in their LCST phase behavior, a property that is exploited for the design of thermal “shape memory” nanoparticles.


O-8:IL02  Parallel Computing with Molecular Motors
H. LINKE, M. LARD, NanoLund, Lund University, Lund, Sweden; T. KORTEN, S. DIEZ, TU Dresden; A. MÅNSSON, Linné University, Kalmar; D. NICOLAU Jr., Molecular Sense; D. NICOLAU Sr., McGill University

We will present a novel paradigm for future parallel computing approaches, based on biological entities. Specifically, we will demonstrate the encoding mathematical problems into networks consisting of nano- or microsized channels and nodes, and will use self-propelled biological agents to explore these networks and find the solution to the encoded mathematical problems. Due to the very large number of agents, the problem is solved in a highly parallel manner and with very high energy efficiency.


Poster Presentations

O:P04  Catalyst Infiltration of SOFC Electrodes Assisted by a Bio-surfactant
O. OZMEN, K. SABOLSKY, J.W. ZONDLO, E.M. SABOLSKY, West Virginia University, Morgantown, WV, USA; S. LEE, K. GERDES, National Energy Technology Laboratory – Regional University Alliance (NETL-RUA), U.S. DOE, Morgantown, WV, USA

The objective of the study is to enhance the solid oxide fuel cell (SOFC) performance by incorporating nano-catalyst particles within the porous NiO/YSZ anode and LSM/GDC cathode electrodes. The focus was to minimize the processing steps and time while improving both the performance and stability of the SOFC. In this work, a mussel inspired bio-adhesive (poly-dopamine, PDA) was used as a surface modifier (surfactant) for a liquid infiltration process. The PDA-assisted infiltration process was completed by dip-coating. This process succeeded in a 3.5 times higher nano-ceria catalyst deposition loading within the electrodes in comparison to the conventional dripping method. One more advantage of the dip-coating protocol was that both electrodes were infiltrated in a singular thermal step. PDA island formation and thickness were assessed under atomic force microscopy and ellipsometry. Voltage-current-power and impedance spectroscopy were used to characterize the electrochemical performance of the impregnated commercial anode-supported button cells and the correlation between nano-catalyst distribution/morphology and cell performances over time were developed.


O:P05  A Two-dimensional Biomimetic Underwater Active Electro-location Position System based on FFT Feature Extraction Cross Localization Algorithm
JIEGANG PENG, School of Automation Engineering and Center for Robotics, University of Electronic Science and Technology of China, Chengdu, Sichuan, P.R. China

In the late 1950s, biologists have discovered that some fishes, which are called weakly electric fish, have an ability to emit a low-frequency electric field actively and sense its change to locate the surrounding object in complete darkness. This ability is called active electrolocation. Inspired by weakly electric fish, engineers have designed electrolocation techniques and systems for underwater robots. In our work, by simulating the function of electrolocation of weakly electric fish, an experimental platform of underwater active electrolocation system which mainly includes launcher, receiver and controller was designed. On the platform, a novel feature, which is named as the location characteristic of underwater active electrolocation system was researched. But for localization algorithm of the time domain feature extraction method, it easy to accept affects by ambient noise. In this paper, based on above location characteristic, a frequency domain Cross Localization algorithm based on Fast Fourier Transform (FFT) feature extraction were adopted to realize the task of positioning in two-dimensional water area. Our work can achieve accurate, fast, efficient positioning in two-dimensional water area and would have reference significance to further underwater detection study.


O:HP06  Observation of Single-nanoparticle Dynamics based on Actively Controllable 2D Supported Lipid Bilayer Platforms
KEUNSUK KIM, YOUNG KWANG LEE, JEONG-WOOK OH, JWA-MIN NAM, Department of Chemistry, Seoul National University, Seoul, South Korea

Fluidity of a supported lipid bilayer (SLB) enables to provide the two-dimensional (2D) stage for the dynamical reactions of molecules and nanoparticles. The observation and tracking of individual single plasmonic nanoparticles on SLB layer can endow the direct information related to the interaction of molecules or functional nanoparticles in various complex chemical, physical, and biological processes. Here, we explored a photostable plasmonic nanoparticle-modified supported lipid bilayer (PNP-SLB) platform with massively parallel in situ analysis of the interaction between DNA-modified PNPs at the single-particle level. The elaborate time-resolved analysis of the scattering intensities for individual PNP probes on the SLB layer recorded by dark-filed microscopy can unravel the limitation of the optically spacial resolution, which enable to monitor the DNA hybridization events occurred at sub 10-nm level and the assembly of nanoparticles. From that analytical view, we can understand the dynamic interactions of metal nanoparticles on the 2D fluidic substrate including the diffusive nature, the clustering process, and the cluster growth kinetics of nanoparticles. Moreover, we can also achieve the ultrasensitive DNA detection with the dynamic range from 300 aM to 300 fM.