Field Of Biomimetics Research Articles

Self-Assembled Nanoporous Biofilms from Functionalized Nanofibrous M13 Bacteriophage.

Highly periodic and uniform nanostructures, based on a genetically engineered M13 bacteriophage, displayed unique properties at the nanoscale that have the potential for a variety of applications. In this work, we report a multilayer biofilm with self-assembled nanoporous surfaces involving a nanofiber-like genetically engineered 4E-type M13 bacteriophage, which was fabricated using a simple pulling method. The nanoporous surfaces were effectively formed by using the networking-like structural layers of the M13 bacteriophage during self-assembly. Therefore, an external template was not required. The actual M13 bacteriophage-based fabricated multilayered biofilm with porous nanostructures agreed well with experimental and simulation results. Pores formed in the final layer had a diameter of about 150–500 nm and a depth of about 15–30 nm. We outline a filter application for this multilayered biofilm that enables selected ions to be extracted from a sodium chloride solution. Here, we describe a simple, environmentally friendly, and inexpensive fabrication approach with large-scale production potential. The technique and the multi-layered biofilms produced may be applied to sensor, filter, plasmonics, and bio-mimetic fields.

Approximating gecko setae via direct laser lithography

The biomimetic replication of dry adhesion present in the gecko’s foot has attracted great interest in recent years. All the microfabrication techniques used so far were not able to faithfully reproduce the hierarchical and complex three-dimensional geometry of the gecko’s setae, with features at the micro- and nano-scale, thus reducing the effectiveness that such conformal morphology could provide. By means of direct laser lithography we fabricated artificial hairs that faithfully reproduce the natural model. This technique allows the fabrication of three-dimensional microstructures with outstanding results in terms of reproducibility and resolution at the micro- and nano-scale. It was possible to get very close to the morphology of the natural gecko setae, especially concerning the hierarchical shape. We designed several morphologies for the setae and studied the effects in terms of adhesion and friction performances compared to the natural counterpart, showing the interplay between morphology, dimensional scaling and materials. Direct laser lithography promises great applications in the biomimetics field, paving the way to the implementation of the concept of hierarchical bioinspired dry adhesives.

Measurement of interaction between water droplets and curved super-hydrophobic substrates in the air

The interaction force is very important in the study of the contact process of droplets and super-hydrophobic substrates. Accurate interaction force measurement in the air has far-reaching impact on industrial production and biomimetic field. However, limited by the evaporation of small droplets, interaction force can only be measured in the liquid by AFM and other devices. A millimetric cantilever was used to make it possible to measure the interaction between droplets and super-hydrophobic substrates in the air. The optical lever was calibrated with the electrostatic force. The super- hydrophobic substrates were fabricated using nano particles and copper grids. We finally acquired the interaction force and wetting time between the droplet and super- hydrophobic substrates with different grid fractions and similar contact angle. The results showed that the interaction force decreased with the increase of the grid fraction. These would open a new way of understanding the mechanism of hydrophobic.

Multiresponsive actuators based on modified electrospun films.

Robot technology has made great progress over the past few decades, and has found wide use in military, industrial and service fields. In recent years, there has been a dramatic increase in the demand for soft robots. However, as a key part, the development of soft actuators capable of low-energy actuation, multi-stimulation response, and large shape deformation is still challenging. In this work, we fabricated multiresponsive actuators based on modified electrospun films. The actuators provided the largest curvatures of 0.83 cm−1, 0.6 cm−1, and 1.05 cm−1, stimulated by humidity, light, and electricity, respectively. Furthermore, we designed a biomimetic application—a crawling robot—which demonstrates excellent potential applications of the actuator in soft robotics, artificial muscles, and the biomimetics field.

An arm-like electrothermal actuator based on superaligned carbon nanotube/polymer composites

A superaligned carbon nanotube film embedded in polymers shows promising applications in the fields of electrothermal actuation because of their homogenous conductivity, good biocompatibility and mechanical properties. We fabricated a simple U-shaped gadget from the composite to investigate the electrothermal actuation mechanism. The gadget can curl to 730°, which is several times larger than existing actuators. A helix-shaped arm-like actuator (artificial arm) was also made from the composite, which exhibited a large twisting deformation (more than 700° twisting, 49.2% length constriction and 26.4% diameter constriction) when driven with low electrical fields (less than 500 V/m or 41 V). The actuation of the U-shaped gadget and the artificial arm can be precisely controlled by the applied voltage or electrical power. The gripping force of the clenched arm is about 4 g, 26 times its own weight. This points to a new way for manipulating objects and its potential application in the biomimetic field.

Theoretical Biomimetics: A biological design-driven concept for creative problem-solving as applied to the optimal sequencing of active learning techniques in educational theory

<p><span lang="EN-US">The article introduces the author’s concept of applying principles of biological design to drive creative problem-solving. It provides a brief background of the field of Biomimetics, which serves as a context for the reader to appreciate how it began with an established field upon which he constructed and adapted his concept to apply to human-made intangibles. A discussion of Theoretical Biomimetics specifies the differences between it and its predecessor. The final section provides the opportunity to see Theoretical Biomimetics in detail applied to education theory to address a problem related to student learning in higher education and how best to establish optimized sequences to implement evidence-based active-learning techniques to fill a void in the literature demonstrating from nature what has worked. The originality lies in the author taking a multidisciplinary approach to synergize a sequence of existing active-learning techniques and apply them to a new area in a new way. </span></p>

A Novel Design of Musculoskeletal Bipedal Robot Applied with Bio-Inspired Elastic Actuation

A rigid actuation method does not allow a humanoid to flexibly compliant with the efforts needed to be exerted in a changing environment. Thus, starting from the studies developed in the biomechanical and biomimetic fields, this paper introduces a novel bipedal robot equipped with a musculoskeletal-like mechanism, in order to obtain the expected compliant locomotion. The robot’s structure consists of extended elastic actuators built from SEAs (Series Elastic Actuators), in order to realize the muscle-tendons like artifact. A novel design of bipedal robot has been built scaling it to a kid-size dimension. An efficient simulation of the robot has also been implemented using the OpenSim Simulator. The kinematics and dynamics of our bipedal model are described in equations. Furthermore, the control architecture has been designed based on a Fuzzy Control and a PID Control approach. Some experiments both on the real and the simulated robot are presented to evaluate the robot’s design and its performances.

Surface Modification of Graphene Oxide with Pyrene Derivatives and their Photo-Switching Behaviors

The characteristics of surface and interface of nanocomposites are favor for exerting some functional properties and widening new applications. Some low-dimensional materials generally have abundant chemical groups and reaction activities. These surface chemical groups of nanomaterials provide a large platform to develop new nanocomposites and applications by surface chemical reaction and surface reconstruction of another kind of materials. Among so many hot-fields materials, graphene and its nanocomposite are developed rapidly. The graphene oxide not only has good charge transferring property, but also has abundant chemical groups on its surface, such as, -COOH, -OH and epoxide group. Therefore, graphene oxide is a good candidate substrate for further constructing other functional materials in nanoscale. The graphene oxide and pyrene derivatives were selected as representative materials for studies. Assembly of pyrene containing –NH2 groups on the surface of graphene oxide was carried out. A series of characterizations were performed by SEM (scanning electron microscopy), TEM (transmission electron microscopy), the FTIR (Fourier-Transform Infrared ) spectra, The UV-Vis (Ultra-violet visible spectroscopy), photoluminescence spectra, et al. The results indicated that the UV-Vis of nanocomposite was almost covered the whole region of visible light, and the results of PL showed strong fluorescence quenching. There was strong interaction between the graphene oxide and pyrene. The photoconductivity response to weak visible light and 808 nm laser were studied based on interdigital electrodes of Au on flexible PET(polyethylene terephthalate) film substrate with casting method. The results showed that graphene oxide modified with pyrene derivatives exhibited that the photocurrent increased obviously to visible light, and photoresponse to weak 808 nm laser emerged photo-switching behavior. It would be developed the light detector to NIR, biomimetic fields or external stimuli driven nanocarriers for biomedical fields, et al.

Nanoindentation investigation of the stress exponent for the creep of dung beetle (Copris ochus Motschulsky) cuticle

ABSTACTWith the rapid development of bionic science, especially the progress that has been made in the fields of biomaterials and biomimetics, there is now great interest in the surface and internal mechanical properties of biological materials at the micro- and nanoscale. The study of micro- and nanoscale biomaterial mechanical properties could enable interdisciplinary applications in materials science, biological science and bionic science. Dung beetle (Copris ochus Motschulsky) cuticle is a viscoelastic material that is both viscous and flexible via elastic deformation under external forces; where stress σ, strain ϵ and elastic modulus E are related in the following way: σ = Eϵ. In addition, as σ is related to the rate of strain, time is also a factor. The stress-strain relationships of various parts of dung beetle cuticle were investigated in this paper. As time increased, the stress and strain of the material were found to decrease and increase, respectively, indicating that when the material was indented for a certain period, the interaction force between the indenter and the material gradually achieved a state of dynamic equilibrium. However, strain continued to occur until reaching a point of equilibrium because of the creep phenomenon. The stress-strain curves showed a strong character in each holding time condition: the longer the holding time, the more flattened the stress-strain curve. These findings will be useful in the advanced design of strong, lightweight, and biomimetic composites.

Piezoelectric Templates - New Views on Biomineralization and Biomimetics.

Biomineralization in general is based on electrostatic interactions and molecular recognition of organic and inorganic phases. These principles of biomineralization have also been utilized and transferred to bio-inspired synthesis of functional materials during the past decades. Proteins involved in both, biomineralization and bio-inspired processes, are often piezoelectric due to their dipolar character hinting to the impact of a template’s piezoelectricity on mineralization processes. However, the piezoelectric contribution on the mineralization process and especially the interaction of organic and inorganic phases is hardly considered so far. We herein report the successful use of the intrinsic piezoelectric properties of tobacco mosaic virus (TMV) to synthesize piezoelectric ZnO. Such films show a two-fold increase of the piezoelectric coefficient up to 7.2 pm V−1 compared to films synthesized on non-piezoelectric templates. By utilizing the intrinsic piezoelectricity of a biotemplate, we thus established a novel synthesis pathway towards functional materials, which sheds light on the whole field of biomimetics. The obtained results are of even broader and general interest since they are providing a new, more comprehensive insight into the mechanisms involved into biomineralization in living nature.

NIR (Near-Infrared) Driven Carbon Nanotube Modified with Dendrimers

Dendrimers and carbon nanotube took an important role in transport and delivery of drugs, gene, et al, however, to improve its functional properties is still a great challenge. Carbon nanotube not only has good biocompatibility but also hold optical adsorption in NIR. In biomimetic and biomedical fields, nanorobots or nanocarriers with external stimuli response for removal the organic pollutants and toxins or drugs in the living body are attractive for research and applications. In this paper, the self-assembly with CNTs containing –COOH and dendrimers having –NH2 groups was carried out. A series of characterizations were performed by SEM (scanning electron microscopy), TEM (transmission electron microscopy), XRD (X-ray diffraction), and Fourier-Transform Infrared (FTIR) spectra. The adsorption properties and releasing characteristics of CNTs modified with dendrimers were performed with simulating drugs. Some meaningful results were obtained. The photoconductivity response to visible light and 808 nm laser with low-power were studied based on interdigital electrodes of Au on flexible PET(polyethylene terephthalate) film substrate. The results indicated that CNTs modified with dendrimers showed good photo-response to visible light and 808 nm laser. It would be developing smart nanorobots with external stimuli response for removal the organic pollutants and toxins or drugs in the living body.

Ecosystem biomimetics for resource use optimization in buildings

An ecomimetic method is developed as an innovative and transdisciplinary design approach rooted in the field of biomimetics. This new method emulates the interrelated complexity of the parts of an ecosystem with the intent to design buildings that are more efficient, effective and holistic. Ecomimetics refers to the design of buildings that mimic ecosystem processes and functions. This approach provides potential opportunities for climate change adaptation and mitigation by optimizing the use of resources in buildings. One challenge to the application of ecomimetics in architecture is the lack of systematic methods supported by scientific research, which may prevent development in this field. A theoretical basis and the initial development of an ecomimetic design method is presented, with a description of each step of the design process. Ecological systems are selected for functional properties that match architectural design goals, and then design tools are used to abstract and transfer those properties to architectural systems. The design tools integrated in the method are from the fields of ecological engineering, systems dynamics and architecture. The case of the Eastgate Center in Harare, Zimbabwe, is used to illustrate the method.

Fabrication of polyurethane(PU) nanotubes with array by wetting anodic aluminium oxide template with polymer solution and melt

The polyurethane (PU) nanotubes with an array structure were fabricated by filtrating a polymer solution or melt into anodic aluminium oxide (AAO) template with 200 nm pores. The results of SEM and TEM illuminated that PU nanotubes were successfully obtained and the wall thickness of PU tube prepared by the 2.5, 5.0 and 10.0 wt% PU solution were respectively 50, 70 and 90 nm. The structure of polymer nanotubes depends strongly on the concentration of PU solution. It was also found the wall of the nanotubes derived from polymer melt is more thicker than that of the nanotubes from polymer solution. The PU nanotubes and nanorods will open the application perspectives of biomimetic materials fields.

Pattern recognition of monosaccharides via a virtual lectin array constructed by boronate affinity-based pH-featured encoding.

Lectin array is an important tool in the fields of carbohydrate chemistry, glycobiology, and glycomics. Because natural lectins are associated with some apparent disadvantages such as tedious purification and easy loss of activity, artificial materials are applied to overcome such shortages by mimicking and replacing lectins in an artificial lectin array, among which boronate affinity-based materials are very outstanding and widely used. However, complicated synthetic works are often involved to design and create boronate affinity-based lectin-mimics. In this work, a facile and novel method was proposed to establish a virtual lectin array based on boronate affinity-based pH-featured encoding for discrimination of monosaccharides by pattern recognition. The dependence of boronate affinity on environmental pH was selected to encode each monosaccharide for feature generation, and the pH-featured encoding was used to construct the virtual lectin array. On the basis of the virtual array, pattern recognition algorithms were applied for data analysis. Monosaccharides were discriminated by principal component analysis, and the relations in the virtual lectin array were unraveled by cluster analysis. In this proof-of-concept work, without complicated synthesis or preparation, the proposed method was successful in mimicking lectin array and discriminating nine elementary monosaccharides found in nature, and it was also a new way of encoding in expanding the applications of boronate affinity-based materials and methods in the field of biomimetics.

Silk fibroin/sodium alginate fibrous hydrogels regulated hydroxyapatite crystal growth.

Use of organic templates for controlling the growth of inorganic crystals is one of the research topics in biomimetic field. In particular, oriented growth of hydroxyapatite (HAp) in organic fibrous matrix is provided a new view angle to study biomineralization of bone and its potential biomedical applications. The crystallization of HAp in fibrous hydrogels could mimic such biomineralization. In this paper, we report HAp nanorod crystal synthesized successfully by a biomimetic method using calcium chloride and ammonium dihydrogen phosphate as reagents in the presence of silk fibroin/sodium alginate (SF/SA) fibrous hydrogels. The effects of influence factors such as mineral times, pH, and temperature on controlling HAp nanorod crystals are discussed. The elongated HAp nanorods with rectangular column are grown with the increase of mineral times in biomimetic process. By changing pH, HAp nanorod crystals are obtained at alkaline condition in fibrous hydrogels. Moreover, compared to other temperatures, rod-shaped HAp crystals were formed at 20°C. The results imply this to be an effective method for preparing HAp crystals with controllable morphology for bone repair application.

Structural Color for Security Printing: Patterned Robust Colloidal Crystals

Structural color is a unique optical property of nano- or microstructured materials with periodic dimensions similar to the wavelength of visible light. Characteristic color is produced through reflectance, interference, scattering, diffraction or refraction of incident light of a specific wavelength in visible spectrum, thereby producing a specific color or so-called structural color. Structural color is seen throughout nature, notably Morpho butterflies and opals present a striking sheen and accompanying vivid hue. Prior analysis of minerals and organisms that produce these distinctive colors allows for continuing analysis of color developing mechanisms [1]. Recently, with improvements in micro-fabrication, trial reproduction of these naturally occurring structural colors is proceeding across the field of Biomimetics [2]. Mono-dispersed micro-particles, structured in an ordered arrangement, are called colloidal crystals. Through Bragg reflection they exhibit structural color with a vivid hue. Colloidal crystals are relatively easy to produce by self-organization, and since dielectric periodic structures can be used as a photonic crystal for controlling electromagnetic waves, it has been extensively studied as a structural color element and photonic crystal. Some of the methods for manufacturing colloidal crystals include capillary method, electric electrophoresis, spin coating, spray coating, and substrate raising [3 - 6]. The color developing mechanism for structural color differs from pigment and does not absorb a specific wavelength, therefore in principle, fading from UV rays should be reduced. These materials can be used in applications that require pigments with excellent light-resistance and durability. In addition, since these colored micro-particle aggregates are non-toxic with a high level of safety, they show promise for wide use in printed materials. Here we present research results involving the formation of a pattern of stable colloidal crystals on various substrates and exploring their suitability for use in printed materials. Monodisperse silica nano-particles with a diameter of 300 nm were dispersed in a highly polar solvent. As the solvent evaporates the particles self-assemble into colloidal crystals. By depositing this dispersed suspension as an ink with a direct write printer (aerosol jet) we confirmed the ability to print colloidal crystals with structural color in any pattern. The cohesion of self-assembled colloidal crystals relies on electrostatic attraction making them extremely brittle with limited practical use. As such, a polymer was added to the suspension to reinforce the colloidal crystal structure with limited influence on the self-assembly mechanism. Thus, a strong coating is produced while also producing the desired color effect. Printed colloidal crystals produced by this method are difficult to reproduce by color copying and traditional printing methods considering the color and gloss change depending on the viewing angle. Figure 1 shows a feature printed using the colloidal crystal ink under various lighting/viewing conditions. Also, since it is possible to direct print any pattern, the method is amenable to variable data printing, providing a tamper prevention effect. Thus, these materials are attractive for use in security printing applications.

ChemInform Abstract: Nanoassemblies Driven by Cyclodextrin‐Based Inclusion Complexation

AbstractReview: 69 refs.

Biologically informed disciplines: a comparative analysis of bionics, biomimetics, biomimicry, and bio-inspiration among others

This article offers a complementary approach to research and education in biologically informed disciplines through the lens of bionics, biomimetics, and biomimicry terminology. For the purpose of developing this approach, we look at past and current contexts in which the three fi elds have emerged and identify three issues: an absence of common ground that unites the fi elds of bionics, biomimetics, and biomimicry while recognizing their contextual differences, a non-standardized use of the terminology that leads to ambiguity within the fi eld of biologically informed disciplines, an incomplete and disorganized historical and contextual knowledge about the fi eld that inhibits a common starting ground for collaboration, and confuses non-scientists who seek biological understanding. We offer a fundamental understanding of the fi elds from theoretical perspective by bringing together opinions of researchers and practitioners of bionics, biomimetics, biomimicry, bio-inspiration and offering a comprehensive analysis of terms culminating in the introduction of an overarching term ‘biologi

A Novel General Chemistry Laboratory: Creation of Biomimetic Superhydrophobic Surfaces through Replica Molding

Biomimetic replicas of superhydrophobic lotus and taro leaf surfaces can be made using polydimethylsiloxane. These replicas faithfully reproduce the microstructures of the leaves’ surface and can be analyzed using contact angle goniometry, self-cleaning experiments, and optical microscopy. These simple and adaptable experiments were used to develop a novel general chemistry laboratory exercise, designed to introduce students to the current fields of materials science and biomimetics, and reinforce concepts such as intermolecular forces and surface tension.

Accurate full-field optical displacement measurement technique using a digital camera and repeated patterns.

In this study, a novel, fast, and accurate in-plane displacement distribution measurement method is proposed that uses a digital camera and arbitrary repeated patterns based on the moiré methodology. The key aspect of this method is the use of phase information of both the fundamental frequency and the high-order frequency components of the moiré fringe before and after deformations. Compared with conventional displacement methods and sensors, the main advantages of the method developed herein are its high resolution, accuracy, speed, low cost, and easy implementation. The effectiveness is confirmed by a simple in-plane displacement measurement experiment, and the experimental results indicate that an accuracy of 1/1000 of the pitch can be achieved for various repeated patterns. This method is useful for various applications ranging from the study of displacement and strain distributions in materials science, the biomimetics field, and mechanical material testing, to secure the integrity of infrastructures.