Design Of Bio-inspired Materials Research Articles

Amyloid-Like Protein-Modified Carbon Nitride as a Bioinspired Material for Enhanced Photocatalytic CO2 Reduction.

Modification of g-C3N4 with metal-free biomaterials through an environmentally friendly, low-energy, facile, and rapid single-step method is desired for the preparation of photocatalysts with efficient activity and high selectivity of CO2 reduction but remains a great challenge. Herein, we develop a phase-transitioned protein modification strategy for photocatalysts through superfast amyloid-like protein assembly on surfaces using a one-step sequential coating method. Metal-free carbon nitride/protein heterojunction composite photocatalysts (the phase-transitioned lysozyme (PTL), phase-transitioned bovine serum albumin (PTB), and phase-transitioned ovalbumin (PTO)-coated carbon nitride@SiO2 (CN@SiO2) and bioinspired carbon nitride hollow nanospheres (CN-HS) obtained by etching of CN@SiO2) are prepared using lysozyme, bovine serum albumin, and ovalbumin. The insulator-semiconductor heterojunctions formed at the protein-carbon nitride interface promote the migration and separation of photogenerated charges. The exposed hydrophobic alkyl and aryl groups of the surface-modified protein enable the formation of a CO2-aqueous solution-photocatalyst three-phase interface on the catalyst surface and the exposed -NH2 groups provide sites for CO2 adsorption, which effectively increases CO2 mass transfer and its adsorption as well as hydrophobicity, promoting CO2 reduction and inhibiting hydrogen production. Therefore, protein modification effectively improves the CO2 reduction activity and CO selectivity. For instance, compared to CN-HS, the CO yield of the PTL-modified CN-HS (1346.5 μmol g-1) increased by 24.5 times and the CO selectivity reached 90.5%. These findings represent a critical advancement in the surface modification of carbon nitride for CO2 reduction and the design of bioinspired materials for various applications.

Designing spongy-bone-like cellular materials: Matched topology and anisotropy

Bone is a natural material with properties such as high specific stiffness and strength. These exceptional mechanical properties are attributed to the meso-scale structure and elastic anisotropy of spongy bone. Replicating the topological traits and mechanical properties of spongy bone presents a novel opportunity to develop high-performance cellular materials. To achieve this, we propose an innovative framework for designing biomimetic cellular materials that match the trabecular structure and elastic anisotropy of spongy bone. This framework introduces a forward-flow design process that utilizes gradient-based feature tuning on a low-dimensional feature vector, transforming the complex inverse design problem into an efficient iterative process. A key innovation in our approach is the use of a pre-trained generative model, SliceGAN, to reconstruct 3D unit cells from 2D micro-CT images. This significantly reduces the cost and time associated with traditional layer-by-layer CT scans typically required for 3D training data. Numerical homogenization is then used to determine the effective elastic stiffness matrix, and a Fourier neural operator is trained to predict these matrices efficiently, greatly enhancing the computational efficiency of the design process. Using this framework, we successfully designed unit cells with topological traits and elastic anisotropy that closely approximate those of natural spongy bone. This opens new avenues for developing spongy-bone-mimetic cellular materials with exceptional mechanical properties. Moreover, the framework's versatility allows it to be extended to the design of other bio-inspired cellular materials.

Extracting Geometry and Topology of Orange Pericarps for the Design of Bioinspired Energy Absorbing Materials.

As a result of evolution, many biological materials have developed irregular structures that lead to outstanding mechanical performances, like high stiffness-to-weight ratios and good energy absorption. However, reproducing these irregular biological structures in synthetic materials remains a complex design and fabrication challenge. Here, a bioinspired material design method is presented that characterizes the irregular structure as a network of building blocks, also known as tiles, and rules to connect them. Rather than replicating the biological structure one-to-one, synthetic materials are generated with the same distributions of tiles and connectivity rules as the biological material and it is shown that these equivalent materials have structure-to-property relationships similar to the biological ones. To demonstrate the method, the pericarp of the orange, a member of the citrus family known for its protective, energy-absorbing capabilities is studied. Polymer samples are generated and characterized under quasistatic and dynamic compression and display spatially-varying stiffness and good energy absorption, as seen in the biological materials. By quantifying which tiles and connectivity rules locally deform in response to loading, it is also determined how to spatially control the stiffness and energy absorption.

Variations in characteristics of bamboo vascular bundles between Dendrocalamus and Bambusa

Unraveling the characteristics of bamboo vascular bundles is critical for understanding their physiology and mechanical properties. However, different bamboo species have different vascular bundles, leading to significant variations in their industrial applications. In this paper, the You Only Look Once algorithm was applied to examine the vascular bundles of several species representatives within Dendrocalamus (Dendrocalamus farinosus, Dendrocalamus asper, and Dendrocalamus latiflorus) and Bambusa (Bambusa pervariabilis, Bambusa textilis, and Bambusa arundinacea), considering their economic and ecological importance. The analysis included the classifications of vascular bundles, their dimensions, and the areas of fiber sheaths. The results showed that the vascular bundles of Dendrocalamus and Bambusa were mainly broken-waist type. Along the radial direction, both Dendrocalamus and Bambusa exhibited gradient variability in vascular bundles, suggesting a similar underlying structural pattern. Quadratic functions could be employed to represent the radial distributions of vascular bundle size and fiber sheath area. Statistically, the fiber sheath area was positively correlated with vascular bundle size (P<0.05). In addition, significant differences in vascular bundles were detected among different bamboo species, which may lead to substantial variations in their mechanical properties. In particular, Bambusa arundinacea had the highest vascular bundle length (724.57 μm) and length/width ratio (1.69), while Dendrocalamus asper had the highest vascular bundle width (552.20 μm) and fiber sheath area (0.22 mm2). Nevertheless, principal component analysis indicated substantial similarity in the vascular bundles of Dendrocalamus and Bambusa. Moreover, the interspecific variations in vascular bundles were notably more pronounced within Dendrocalamus compared to those observed within Bambusa. Overall, our study examined the variations in vascular bundles between Dendrocalamus and Bambusa, offering insights that hold significant potential for bamboo taxonomy and the design of bio-inspired materials.

The effects of histidine substitution of aromatic residues on the amyloidogenic properties of the fragment 264–277 of nucleophosmin 1

Histidine (His) plays a key role in mediating protein interactions and its unique side chain determines pH responsive self-assembling processes and thus in the formation of nanostructures. In this study, To identify novel self-assembling bioinspired sequences, we analyzed a series of peptide sequences obtained through the point mutation of aromatic residues of 264–277 fragment of nucleophosmin 1 (NPM1) with single and double histidines. Through several orthogonal biophysical techniques and under different pH and ionic strength conditions we evaluated the effects of these substitutions in the amyloidogenic features of derived peptides. The results clearly indicate that both the type of aromatic mutated residue and its position can have different effect on amyloid-like behaviors. They corroborate the crucial role exerted by Tyr271 in the self-assembling process of CTD of NPM1 in AML mutated form and add novel insights in the accurate investigation of how side chain orientations can determine successful design of innovative bioinspired materials.

Learning from Nature to Achieve Material Sustainability: Generative AI for Rigorous Bio-inspired Materials Design

Learning from Nature to Achieve Material Sustainability: Generative AI for Rigorous Bio-inspired Materials Design

Dynamic Structural Change of Plant Epidermal Cell Walls under Strain.

The molecular foundations of epidermal cell wall mechanics are critical for understanding structure-function relationships of primary cell walls in plants and facilitating the design of bioinspired materials. To uncover the molecular mechanisms regulating the high extensibility and strength of the cell wall, the onion epidermal wall is stretched uniaxially to various strains and cell wall structures from mesoscale to atomic scale are characterized. Upon longitudinal stretching to high strain, epidermal walls contract in the transverse direction, resulting in a reduced area. Atomic force microscopy shows that cellulose microfibrils exhibit orientation-dependent rearrangements at high strains: longitudinal microfibrils are straightened out and become highly ordered, while transverse microfibrils curve and kink. Small-angle X-ray scattering detects a 7.4nm spacing aligned along the stretch direction at high strain, which is attributed to distances between individual cellulose microfibrils. Furthermore, wide-angle X-ray scattering reveals a widening of (004) lattice spacing and contraction of (200) lattice spacing in longitudinally aligned cellulose microfibrils at high strain, which implies longitudinal stretching of the cellulose crystal. These findings provide molecular insights into the ability of the wall to bear additional load after yielding: the aggregation of longitudinal microfibrils impedes sliding and enables further stretching of the cellulose to bear increased loads.

Probing Intersystem Crossing in Multi-brominated Eumelanin through Transient Absorption and Surface Hopping Dynamics

Achieving intersystem crossing (ISC) through structural tuning in biological systems is an evolving area for therapeutic and materials research. Eumelanin, a natural pigment, offers huge potential for bio-inspired material design,...

BioinspiredLLM: Conversational Large Language Model for the Mechanics of Biological and Bio-Inspired Materials.

The study of biological materials and bio-inspired materials science is well established; however, surprisingly little knowledge is systematically translated to engineering solutions. To accelerate discovery and guide insights, an open-source autoregressive transformer large language model (LLM), BioinspiredLLM, is reported. The model is finetuned with a corpus of over a thousand peer-reviewed articles in the field of structural biological and bio-inspired materials and can be prompted to recall information, assist with research tasks, and function as an engine for creativity. The model has proven that it is able to accurately recall information about biological materials and is further strengthenedwith enhanced reasoning ability, as well as with Retrieval-Augmented Generation (RAG) to incorporate new data during generation that can also help to traceback sources, update the knowledge base, and connect knowledge domains. BioinspiredLLM also has shown to develop sound hypotheses regarding biological materials design and remarkably so for materials that have never been explicitly studied before. Lastly, the model shows impressive promise in collaborating with other generative artificial intelligence models in a workflow that can reshape the traditional materials design process. This collaborative generative artificial intelligence method can stimulate and enhance bio-inspired materials design workflows. Biological materials are at a critical intersection of multiple scientific fields and models like BioinspiredLLM help to connect knowledge domains.

Role of atomistic modeling in bioinspired materials design: A review

Biological materials have consistently intrigued researchers due to their remarkable properties and intricate structure–property-function relationships. Deciphering the pathways through which nature has bestowed its exceptional properties represents a complex challenge. The hierarchical architectures of biomaterials are recognized as the basis for mechanical robustness. Moreover, it is well-established that the intriguing properties of biomaterials arise primarily from the architecture at the nanoscale, particularly the abundant carefully designed interfaces. Driven by the diverse functionality and the increasing comprehension of the underlying design mechanisms in biomaterials, substantial endeavors have been directed toward emulating the architectures and interactions in synthetic materials. By reviewing atomistic modeling of nacre, wood, and coconut endocarp, in this work, we aim at highlighting the significant role of atomistic modeling in revealing nanoscale strengthening and toughening mechanisms of biomaterials, subsequently advancing the development of bioinspired material.

A nanofibril network model of biological silks

Biological silks produced by, for examples, spiders and silkworms exhibit exceptional mechanical properties, including high strength, toughness, and extensibility, which arise from their optimized hierarchical structures. Understanding the relationship between their structures and properties is crucial for the design of bioinspired materials. However, it remains a challenge to recapitulate their macroscopic mechanical behaviors of biological silks with a micromechanical model that integrates the physical mechanisms of deformation and failure, such as molecular unfolding and nanofibrous remodeling. In this paper, we propose a nanofibril network (NFN) model to analyze the deformation, damage, and fracture processes of biological silks. The NFN model reveals how molecular unfolding affects the deformation and fracture of biological silks at the nanofibrous scale. It is observed that molecular unfolding consecutively occurs, evolving into band or elliptical morphologies with increasing tensile strain. Intermolecular hydrogen bonds tend to stabilize the expansion of unfolding zones. The NFN model also unveils how the instability of molecular unfolding is suppressed by nanofibrous architecture and how intermolecular hydrogen bonds interact with intramolecular unfolding to toughen the biological silk. This work provides a theoretical tool for studying and designing biomimetic nanofibrous materials.

Development of bioinspired damage-tolerant calcium phosphate bulk materials

ABSTRACT Improving the damage tolerance and reliability of ceramic artificial bone materials, such as sintered bodies of hydroxyapatite (HAp), that remain in vivo for long periods of time is of utmost importance. However, the intrinsic brittleness and low damage tolerance of ceramics make this challenging. This paper reports the synthesis of highly damage tolerant calcium phosphate-based materials with a bioinspired design for novel artificial bones. The heat treatment of isophthalate ion-containing octacalcium phosphate compacts in a nitrogen atmosphere at 1000°C for 24 h produced an HAp/β-tricalcium phosphate/pyrolytic carbon composite with a brick-and-mortar structure (similar to that of the nacreous layer). This composite exhibited excellent damage tolerance, with no brittle fracture upon nailing, likely attributable to the specific mechanical properties derived from its unique microstructure. Its maximum bending stress, maximum bending strain, Young’s modulus, and Vickers hardness were 11.7 MPa, 2.8 × 10‒ 2, 5.3 GPa, and 11.7 kgf/mm2, respectively. The material exhibited a lower Young’s modulus and higher fracture strain than that of HAp-sintered bodies and sintered-body samples prepared from pure octacalcium phosphate compacts. Additionally, the apatite-forming ability of the obtained material was confirmed in vitro, using a simulated body fluid. The proposed bioinspired material design could enable the fabrication of highly damage tolerant artificial bones that remain in vivo for long durations of time.

Building block aspect ratio controls assembly, architecture, and mechanics of synthetic and natural protein networks

Fibrous networks constructed from high aspect ratio protein building blocks are ubiquitous in nature. Despite this ubiquity, the functional advantage of such building blocks over globular proteins is not understood. To answer this question, we engineered hydrogel network building blocks with varying numbers of protein L domains to control the aspect ratio. The mechanical and structural properties of photochemically crosslinked protein L networks were then characterised using shear rheology and small angle neutron scattering. We show that aspect ratio is a crucial property that defines network architecture and mechanics, by shifting the formation from translationally diffusion dominated to rotationally diffusion dominated. Additionally, we demonstrate that a similar transition is observed in the model living system: fibrin blood clot networks. The functional advantages of this transition are increased mechanical strength and the rapid assembly of homogenous networks above a critical protein concentration, crucial for in vivo biological processes such as blood clotting. In addition, manipulating aspect ratio also provides a parameter in the design of future bio-mimetic and bio-inspired materials.

Potentialities of Agave sisalana Fibers in the Design of Bioinspired Materials and Artifacts

Potentialities of Agave sisalana Fibers in the Design of Bioinspired Materials and Artifacts

An Immunomodulatory Biomimetic Single-Atomic Nanozyme for Biofilm Wound Healing Management.

Nanozyme-driven catalytic antibacterial therapy has become a promising modality for bacterial biofilm infections. However, current catalytic therapy of biofilm wounds is severely limited by insufficient catalytic efficiency, excessive inflammation, and deep tissue infection. Drawing from the homing mechanism of natural macrophages, herein, a hollow mesoporous biomimetic single-atomic nanozyme (SAN) is fabricated to actively target inflamed parts, suppress inflammatory factors, and eliminate deeply organized bacteria for enhance biofilm eradication. In the formulation, this biomimetic nanozyme (Co@SAHSs@IL-4@RCM) consists of IL-4-loaded cobalt SANs-embedded hollow sphere encapsulate by RAW 264.7 cell membrane (RCM). Upon accumulation at the infected sites through the specific receptors of RCM, Co@SAHS catalyze the conversion of hydrogen peroxide into hydroxyl radicals and are further amplify by NIR-II photothermal effect and glutathione depletion to permeate and destroy biofilm structure. This behavior subsequently causes the dissociation of RCM shell and the ensuing release of IL-4 that can reprogram macrophages, enabling suppression of oxidative injury and tissue inflammation. The work paves the way to engineer alternative "all-in-one" SANs with an immunomodulatory ability and offers novel insights into the design of bioinspired materials.

Mechanics and properties of fish fin rays in nonlinear regimes of large deformations

Fins from ray-finned fishes do not contain muscles, yet fish can change the shape of their fins with high precision and speed, while producing large hydrodynamic forces without collapsing. This remarkable performance has been intriguing researchers for decades, but experiments have so far focused on homogenized properties, and models were developed only for small deformations and small rotations. Here we present fully instrumented micromechanical tests on individual rays from Rainbow trout in both morphing and flexural deflection mode and at large deflections. We then present a nonlinear mechanical model of the ray that captures the key structural elements controlling the mechanical behavior of rays under large deformations, which we successfully fit onto the experiments for property identification. We found that the flexural stiffness of the mineralized layers in the rays (hemitrichs) is 5-6 times lower than their axial stiffness, an advantageous combination to produce stiff morphing. In addition, the collagenous core region can be modeled with spring elements which are 3-4 orders of magnitude more compliant than the hemitrichs. This fibrillar structure provides negligible resistance to shearing from the initial position, but it prevents buckling and collapse of the structure at large deformations. These insights from the experiments and nonlinear models can serve as new guidelines for the design of efficient bioinspired stiff morphing materials and structures at large deformations. Statement of significanceFins from ray-finned fishes do not contain muscles, yet fish can change the shape of their fins with high precision and speed, while producing large hydrodynamic forces without collapsing. Experiments have so far focused on homogenized properties, and models were developed only for small deformations and small rotations providing limited insight into the rich nonlinear mechanics of natural rays. We present micromechanical tests in both morphing and flexural deflection mode on individual rays, a nonlinear model of the ray that captures the mechanical behavior of rays under large deformations and combine microCT measurements to generate new insights into the nonlinear mechanics of rays. These insights can serve as new guidelines for the design of efficient bioinspired stiff morphing materials and structures at large deformations.

Bioinspired “aerogel grating” with metasurfaces for durable daytime radiative cooling for year-round energy savings

Passive radiative cooling strategy shows a great potential in mitigating global warming and reducing energy consumption. However, existing radiative coolers generally show poor solar-reflection and be easily dampened by environmental aging, making the cooling ineffective. Mimicking the biological design for thermoregulation has given promise for realizing high performance and long time cooling. Here, inspired by structural whiteness in butterflies, we developed a sustainable cellulose nanocrystal aerogel grating (CAG) with designable metasurfaces for efficient radiative cooling, which can be achieved by using copper meshes as well as manipulating the 2D confined freeze casting process. The simulation indicates that the regular tubes and irregular gully on the aerogel surface act as gratings to achieve diffraction and broadband reflection of sunlight. Such CAG exhibits ultrahigh solar reflectance (97.4 %), high infrared emittance (94 %), and anti environmental aging function (anti-ultraviolet light/ contamination). It achieves a sub-ambient temperature drop of 10.5 °C under direct sunlight and still approximately 9.4 °C even after 6 months of exposure to hot weather. Building simulations demonstrate that CAG can save 47 % of the worldwide energy consumption for cooling each year. This work provides insight into the design of bioinspired thermal-regulating materials to save energy consumption.

Novel cuttlebone-inspired hierarchical bionic structure enabled high energy absorption

Bionic design is an effective strategy for obtaining lightweight, high-performance, and even multifunctional structures. Here, we found a novel hierarchical lamellar chamber microstructure in cuttlebone. To determine whether and how this cuttlebone-like hierarchical structure (CL-H) works on its mechanical properties, various lattices with CL-H cellular structure through digital light processing technique were designed and fabricated. Results showed that the CL-H lattice had excellent mechanical performances, achieving specific energy absorption up to a dozen times that of the non-hierarchical cuttlebone-like structure (CL) and triply periodic minimal surface structures. The CL-H lattices presented progressive failure behaviors depending on the numbers of sub-chambers. Furthermore, the mechanisms of energy absorption characteristic and failure behavior were systematically analyzed by combining microstructure examination and FEM simulation, and a schematic model was proposed. This study shed light on the design and engineering of advanced bio-inspired materials with excellent mechanical properties.

A crack-bridging model of brick and mortar architecture considering the anisotropic property

The attainment of both strength and toughness is a vital requirement for most engineering materials. Unfortunately these properties are generally mutually exclusive. Biological materials, which defeat the conflict of strength versus toughness, provide prototypes to design artificial composites. This paper presents a fracture model of brick and mortar architectures considering the anisotropy of natural materials, to reveal the toughening mechanism of crack-bridging and provide some guidelines for the design of high-performance bioinspired materials. Firstly, we establish an microstructure-based anisotropic fracture model. It is found that to accurately predict the fracture toughness, it is necessary to take into account material anisotropy. Then, the model is used to explore the toughening effect of geometric sizes and material parameters. The results demonstrate that the aspect ratio of brick and the stiffness ratio of brick and mortar are key parameters to influence fracture toughness. In addition, crack-bridging provides a dominant contribution to the crack resistance in the early stage of crack growth, and its contribution is gradually attenuated with crack growth.

Integrated data-driven modeling and experimental optimization of granular hydrogel matrices

Integrated data-driven modeling and experimental optimization of granular hydrogel matrices