Bio-inspired Approach Research Articles

Enhanced UAV-aided vehicular delay tolerant network (VDTN) routing for urban environment using a bio-inspired approach

The evolution of VDTN routing came to solve the problem of routing in sparse Vehicular Ad-hoc Networks (VANETs). Recently, the implication of Unmanned Aerial Vehicles (UAVs) in VANET communication has gathered quicker information dissemination than Roadside Units (RSUs) in urban VANETs, where ground vehicles’ mobility is restricted by the topology of city roads. Gradually, UAVs are emerging for VDTNs: UAV-aided VDTN (UVDTN) routing field has been introduced for sparse areas in order to reduce the network gaps between Vehicle-to-Vehicle (V2V) connections. Meanwhile, the conventional UVDTN routing protocols expose the short contact opportunity time in the case of Vehicle-to-UAV (V2U) and UAV-to-Vehicle (U2V) connections. This constraint entails more congested bundles’ flooding rates and a higher number of lost bundle copies compared to V2V-based forwarding. In this paper, a bio-inspired UVDTN routing protocol is conceived to improve the bundles’ forwarding between ground vehicles and UAVs in terms of flooding optimization and Quality-of-Service (QoS) performances for urban VANET environments. For this purpose, a swarm-inspired approach called the Social Spider Optimization (SSO) is proposed. SSO seeks to find a better selection of next Store-Carry-and-Forward (SCF) relay nodes specifically for V2U and U2V connections. In order to control the bundle replication rate and enhance bundles’ delivery ratio and delay, the proposed bio-inspired UVDTN protocol adjusts the SCF selection decision. The latter is based on predefined historical knowledge-based forwarding parameters and urban geographic topology information. The proposed bio-inspired routing protocol is simulated using the Opportunistic Network Environment (ONE) simulator and compared to a few VDTN and UVDTN routing protocols.

Unified GRF-based control for adjusting hopping frequency with various robot configurations

The highly dynamic hybrid nature of legged locomotion makes it a very challenging task to control. A proper control strategy, besides the ability to generate stable motions, should also possess generalization capabilities and adjustability to different conditions. In this regard, this work takes a step forward in promoting the concept of Force Modulated Compliance (FMC) control as a bioinspired reflex-based control approach and assesses its potential in generating various hopping motions. The FMC is an easy-to-tune and simplified representation of the neuromuscular control, which functions as an adjustable spring modulated by the ground reaction force. We implemented the FMC controller on EPA-Hopper-II which is an extension of our previous electric-pneumatic actuation (EPA) designs. By optimizing control parameters for hopping frequencies of and different PAM configurations in the robot structure, we show that FMC can generate stable hopping motions and adapt to different configurations. The optimization results also show that leg stiffness has a high correlation with normalized energy consumption. Increases in leg stiffness decrease the normalized energy consumption and vice versa. The outcomes of this study, particularly the highlighted generalization of the FMC control, open new doors for efficient control of legged robots and assistive devices.

Green Communication in Internet of Things: A Hybrid Bio-Inspired Intelligent Approach.

Clustering is a promising technique for optimizing energy consumption in sensor-enabled Internet of Things (IoT) networks. Uneven distribution of cluster heads (CHs) across the network, repeatedly choosing the same IoT nodes as CHs and identifying cluster heads in the communication range of other CHs are the major problems leading to higher energy consumption in IoT networks. In this paper, using fuzzy logic, bio-inspired chicken swarm optimization (CSO) and a genetic algorithm, an optimal cluster formation is presented as a Hybrid Intelligent Optimization Algorithm (HIOA) to minimize overall energy consumption in an IoT network. In HIOA, the key idea for formation of IoT nodes as clusters depends on finding chromosomes having a minimum value fitness function with relevant network parameters. The fitness function includes minimization of inter- and intra-cluster distance to reduce the interface and minimum energy consumption over communication per round. The hierarchical order classification of CSO utilizes the crossover and mutation operation of the genetic approach to increase the population diversity that ultimately solves the uneven distribution of CHs and turnout to be balanced network load. The proposed HIOA algorithm is simulated over MATLAB2019A and its performance over CSO parameters is analyzed, and it is found that the best fitness value of the proposed algorithm HIOA is obtained though setting up the parameters, number of rooster, number of hen’s and swarm updating frequency . Further, comparative results proved that HIOA is more effective than traditional bio-inspired algorithms in terms of node death percentage, average residual energy and network lifetime by 12%, 19% and 23%.

Construction of Bio-inspired Film with Engineered Hydrophobicity to Boost Interfacial Reaction Kinetics of Aqueous Zinc-Ion Batteries.

Aqueous zinc-ion batteries typically suffer from sluggish interfacial reaction kinetics and drastic cathode dissolution owing to the desolvation process of hydrated Zn2+ and continual adsorption/desorption behavior of water molecules, respectively. To address these obstacles, a bio-inspired approach, which exploits the moderate metabolic energy of cell systems and the amphiphilic nature of plasma membranes, is employed to construct a bio-inspired hydrophobic conductive poly(3,4-ethylenedioxythiophene) film decorating α-MnO2 cathode. Like plasma membranes, the bio-inspired film can "selectively" boost Zn2+ migration with a lower energy barrier and maintain the integrity of the entire cathode. Electrochemical reaction kinetics analysis and theoretical calculations reveal that the bio-inspired film can significantly improve the electrical conductivity of the electrode, endow the cathode-electrolyte interface with engineered hydrophobicity, and enhance the desolvation behavior of hydrated Zn2+ . This results in an enhanced ion diffusion rate and minimized cathode dissolution, thereby boosting the overall interfacial reaction kinetics and cathode stability. Owing to these intriguing merits, the composite cathode can demonstrate remarkable cycling stability and rate performance in comparison with the pristine MnO2 cathode. Based on the bio-inspired design philosophy, this work can provide a novel insight for future research on promoting the interfacial reaction kinetics and electrode stability for various battery systems.

Pectin mediated green synthesis of CuO nanoparticles: evaluation of its cytotoxicity, antioxidant and anti-human cervical cancer properties

Regarding applicative, facile, green chemical research, a bio-inspired approach is being reported for the synthesis of CuO nanoparticles by pectin (PEC) as a natural reducing and stabilizing agentin alkaline medium without using any toxic reducing agent. The biosynthesized CuO NPs@Pectin were characterized by advanced physicochemical techniques like ultraviolet–visible (UV–Vis), Fourier Transformed Infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Energy Dispersive X-ray spectroscopy (EDX) and X-ray Diffraction (XRD) study. It has been established that pectin-stabilized copper nanoparticles have a spherical shape with a mean diameter from approximately 10 nm. To survey the cytotoxicity and anti-human cervical cancer effects of CuO NPs@Pectin, MTT assay was used on C-33 A [c-33a], SiHa, Ca Ski, DoTc2 4510, HT-3 and LM-MEL-41 cell lines. The resulting IC50 values of the CuO NPs@Pectin against C-33 A [c-33a], SiHa, Ca Ski, DoTc2 4510, HT-3 and LM-MEL-41 cell lines were 231, 214, 243, 376, 315 and 169 µg/mL, respectively. Antioxidant properties of CuO NPs@Pectin were surveyed through the DPPH test in presence of butylated hydroxytoluene as the positive control. The CuO NPs@Pectin inhibited half of the DPPH molecules in the concentration of 98 µg/mL. The cell viability of the treated cell lines was found to reduce dose-dependently over the CuO NPs@Pectin nanocomposite. After approving the above results in the clinical trial studies, the CuO NPs@Pectin can be used as a chemotherapeutic drug for the treatment of several types of cervical cancers.

Evolving neural networks through bio-inspired parent selection in dynamic environments

Environmental variability often degrades the performance of algorithms designed to capture the global convergence of a given search space. Several approaches have been developed to challenge environmental uncertainty by incorporating biologically inspired notions, focusing on crossover, mutation, and selection. This study proposes a bio-inspired approach called NEAT-HD, which focuses on parent selection based on genetic similarity. The originality of the proposed approach rests on its use of a sigmoid function to accelerate species formation and contribute to population diversity. Experiments on two classic control tasks were performed to demonstrate the performance of the proposed method. The results show that NEAT-HD can dynamically adapt to its environment by forming hybrid individuals originating from genetically distinct parents. Additionally, an increase in diversity within the population was observed due to the formation of hybrids and novel individuals, which has never been observed before. Comparing two tasks, the characteristics of NEAT-HD were improved by appropriately setting the algorithm to include the distribution of genetic distance within the population. Our key finding is the inherent potential of newly formed individuals for robustness against dynamic environments.

A Study to Enhance the Route Optimization Algorithm for the Internet of Vehicle

In the Internet of Things (IoT), the advancement of the new modern era of Internet-off driving, known as the Internet of Vehicles (IoV), is aimed at the Intelligent Transportation System (ITS) to improve road safety and traffic. Therefore, IoV is better for traffic management. But perhaps, the main challenges in this type of network are that timely decision to make adequate decisions by a driver under certain conditions of rapid change in topology, high vehicular mobility, and frequent link failures is hard to improve road safety. Therefore, an optimized and congestion-free route is required to collect real-time data from vehicles. Thus, some of the latest bioinspired optimization routing algorithms in the IoV environment are presented in this study. Hence, monitoring speed limits, pollution checks, and emergency responses to traffic accidents should also be considered while performing vehicle routing to avoid traffic problems. In the previous decades, many route-directing protocols for the IoV environment have been proposed that can handle the requirements of reliability and security. But such routing of protocols suffers from high complexity and scalability limitations in big-scale networks, routing overlays, etc. Therefore, their strengths, weaknesses, and critical characteristics are compared using various criteria for such algorithms. Then, a suggestion is made to propose a prescribed combined model of a multimodular bioinspired approach to IoV routing. Finally, the main future directions of research in this sector are highlighted.

A bio-inspired approach: Firefly algorithm for Multi-Depot Vehicle Routing Problem with Time Windows

In this research, an improved bio-inspired metaheuristic named firefly is utilized to solve the Multi-Depot Vehicle Routing Problem with Time Windows (MDVRP-TW) and it is a generalization of Vehicle Routing Problem with Time Windows. This paper discusses the use of biological intelligence in analysis and optimization on MDVRP-TW. The objective of the MDVRP-TW is to minimize the overall distance, means of transportation within a specified time gap, along with other constraints such as limitation of vehicle capacity, restrictions of route duration length to satisfy the customer’s requirements. The routes must be designed where each customer is visited only once in a particular time gap with one vehicle and all the routes must originate and end at the same depot. The overall demand should not go beyond the vehicle’s capacity on each route. Multi-objective problems have attracted the attentions of many researchers in recent years, as they are more closely related to real-world situations. However, transportation is a significant factor for the current society, exhibiting and planning a complicated transport system was a very thought-provoking task. Many research studies have shown several successful metaheuristics and heuristic methodologies to solve MDVRP-TW in which, instead of a single depot, numerous depots with varying locations. In this work considered both the earliest time and latest arrival time window (double-sided time window). It is assumed that if an arrival time is more significant than the latest time, it will lead to an infeasible solution whereas, if an arrival time is lesser than the earliest time, then it will lead to a waiting time. However, due to its challenging task and multi-objective and limitations, there is still a space to solve it. In this work, a novel technique that combines an improved firefly algorithm (IFA), which uses different mechanisms, namely, inter-depot approach in assignment phase, Clarke & wright algorithm, and local search method in routing and scheduling phase were applied. The suggested technique has been evaluated using Cordeau standard benchmark instances and proved the technique’s novelty and feasibility. In a few circumstances, the modified firefly algorithm outperforms other algorithms, and optimal benchmark solution in terms of results and competence.

Distributed leader-following formation control for multiple nonholonomic mobile robots via bioinspired neurodynamic approach

This paper investigates the distributed leader-following formation control problem for multiple nonholonomic wheeled mobile robots via a bioinspired neurodynamic approach. To do this, first, we develop a distributed estimator for each follower robot which uses its own information and the information of its neighboring robots to estimate the leader’s states. Second, a formation tracking control law is proposed for each follower robot based on the estimated states of the leader using the backstepping technique. Then, a bioinspired neurodynamics-based backstepping controller is designed to solve the impractical velocity jumps problem. Furthermore, Lyapunov function-based approach is utilized to derive sufficient conditions which guarantee asymptotic stability of the multiple mobile robot system. Finally, simulation results are presented to illustrate the effectiveness of the proposed controllers.

Anti-inflammatory and immunomodulatory properties of Mentha piperita green-formulated gold nanoparticles and its effect on ovalbumin-induced asthma and lung pathological changes in rats

Regarding applicative, facile, green chemical research, a bio-inspired approach is being reported for the synthesis of Au nanoparticles by Mentha piperita as a natural reducing and stabilising agent in alkaline medium without using any toxic reducing agent. The biosynthesized Au NPs@Mentha piperita were characterised by advanced physicochemical techniques like ultraviolet-visible (UV-Vis), Fourier Transformed Infrared spectroscopy (FT-IR), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Energy Dispersive X-ray spectroscopy (EDX), and X-ray Diffraction (XRD) study. It has been established that Au NPs@Mentha piperita have a spherical shape with a mean diameter from ∼10 nm. To survey the cytotoxicity effects of Au NPs@Mentha piperita, MTT assay was used on HUVEC cell line. To survey the antioxidant properties of Au NPs@Mentha piperita, the DPPH test was used in the presence of butylated hydroxytoluene as the positive control. The Au NPs@Mentha piperita inhibited half of the DPPH molecules in the concentration of 113 µg/mL. In the in vivo, wistar rats were divided to four groups; non-sensitised, sensitised to ovalbumin, sensitised and treated with dexamethasone (1.25 μg/mL), and Au NPs@Mentha piperita (5 μg/mL) in drinking water for 21 days. The levels of total protein (TP), phospholipase A2 (PLA2), immunoglobulin E (IgE), IFN-γ/IL-4 ratio, interferon gamma (IFN-γ), and interleukin 4 (IL-4) in BALF, and lung pathological changes were examined. A significant increase in PLA2, IgE, IL-4, and TP levels, all lung pathological indices as well as significant decrease in IFN-γ/IL-4 ratio was seen in the asthmatic compared to the control rats. Treatment with Au NPs@Mentha piperita (5 μg/mL) resulted in decreased PLA2, IgE, IL-4, and TP levels, but increased IFN-γ/IL-4 ratio compared to untreated sensitised rats. The Au NPs@Mentha piperita significantly improved the pathological changes of sensitised rats. The improvement effects of higher concentrations of the Au NPs@Mentha piperita extract were significantly more than those of dexamethasone. The improvement effects of Au NPs@Mentha piperita on pathological changes, immunological and inflammatory markers in sensitised rats comparable or even more potent than dexamethasone suggests the therapeutic potential of the nanoparticle in asthma. After confirming these results in clinical trial studies, Au NPs@Mentha piperita can be used as a new drug for the treatment of asthma in humans.

Optimization of Receivers' Field of Views in Multi-User VLC Networks: A Bio-Inspired Approach

Visible light communication is a well-known emerging technology that enables high data rate wireless access in indoor environments by making dual-us e of light-emitting diode luminaires for providing lighting and communication. Managing multiple access and addressing the user's mobility are among the current challenges of this technology. To manage multiple access interference arising from unintended received signals of other users, different approaches have been proposed so far, including zero-forcing precoding and broadcasting of the users' signals. However, by this approach, the network performance is sensitive to the users' locations, since they affect the correlation properties of the network channel matrix. A higher correlation (e.g., for the case of users getting closer together) results in a performance degradation. To mitigate this, we propose a novel approach of optimizing the receivers field-of-views based on the bio-inspired particle swarm optimization in order to adapt to the users' location, and hence, improve the network's robustness. The efficiency of the proposed method is demonstrated through numerical simulations.

Bio-inspired Search Approach Cross-Domain Location Mapping for Smart Mobile Service System

The health care service sector is very critical in every country. Although governments have made significant efforts to improve health infrastructure and train more qualified health professionals, the majority of them cannot find jobs within public health facilities. Furthermore, patients queue at health care facilities for hours daily for basic health care services while job creation and reducing these long queues remains a challenge in most developing countries. By leveraging the ubiquitousness of mobile technology, patients can be assisted to request health care services, to be delivered at their locations by qualified healthcare professionals. Given the critical nature of health care services, it is imperative to deliver services on-time without delays. In this regard, finding an optimal path between the service originator and the location of health care professionals is important. In this study, location data was used to provide near-optimal location information by mapping location data between patient and health professional domains. Our mapping approach centers on the hunting behavior of the Kestrel bird and through this, an algorithm is proposed for cross-domain location mapping. The mathematical model that is proposed in this study's major contribution as well as the application of the Kestrel-based Search Algorithm (KSA) for location data generation to find the optimal distance from an initial location. The result is promising in terms of the optimal distance between two locations using the haversine and equirectangular approxima¬tion formulas. The KSA was juxtaposed with other renowned meta-heuristic algorithms such as the BAT, Wolf Search Algorithm with Minus Previous Step (WSA-MP), and Ant Colony Optimization (ACO). Results obtained indicate that the equirectangular approxima¬tion formula with the KSA has the minimal distance which in practice implies that nature-inspired algorithms can be adopted in location mapping where randomization is essential, especially in a mobile health application.

Calcium peroxide aids tyramine-alginate gel to crosslink with tyrosinase for efficient cartilage repair

The innate cartilage extracellular matrix is avascular and plays a vital role in innate chondrocytes. Recapping the crucial components of the extracellular matrix in engineered organs via polymeric gels and bioinspired approaches is promising for improving the regenerative aptitude of encapsulated cartilage/chondrocytes. Conventional gel formation techniques for polymeric materials rely on employing oxidative crosslinking, which is constrained in this avascular environment. Further, poor mechanical properties limit the practical applications of polymeric gels and reduce their therapeutic efficacy. Herein, the purpose of this study was to develop a bioadhesive gel possessing dual crosslinking for engineering cartilage. Tyramine (TYR) was first chemically conjugated to the alginate (ALG) backbone to form an ALG-TYR precursor, followed by the addition of calcium peroxide (CaO2); calcium ions of CaO2 physically crosslink with ALG, and oxygen atoms of CaO2 chemically crosslink TYR with tyrosinase, thus enabling dual/enhanced crosslinking and possessing injectability. The ALG-TYR/tyrosinase/CaO2 gel system was chemically, mechanically, cellularly, and microscopically characterized. The gel system developed herein was biocompatible and showed augmented mechanical strength. The results showed, for the first time, that CaO2 supplementation preserved cell viability and enhanced the crosslinking ability, bioadhesion, mechanical strength, chondrogenesis, and stability for cartilage regeneration.

Integrated Photo-Plasmonic coupling of bioinspired Sharp-Edged silver Nano-particles with Nano-films in extended cavity functional interface for Cellphone-aided femtomolar sensing

Plasmonic silver nanoparticles (AgNPs) of anisotropic geometries are being increasingly explored in advanced functional nanointerfaces. Here, Ag nanocubes were synthesized using bioinspired and frugal approach with the use of proteins extracted from sesame oil seed cakes and UV-exposure methodology. The protein functions as both the reducing and capping agent via photo-induced electron transfer mechanism. The obtained AgNPs were evaluated in surface plasmon-coupled emission (SPCE) platform in different functional nanointerfaces. The augmented emission was utilized for cellphone-based femtomolar sensing of SPCE reporter molecule, rhodamine B (RhB). The user-eco-friendly approach developed here would be of utility for biosensing in resource-scarce settings.

Bionic orientation method based on polarization imaging in HDR scenes.

An increasing number of bio-inspired navigation approaches have been designed based on polarization cameras. However, digital cameras can sense a much narrower field of vision than the vision of insects or human beings. In this study, we propose an adaptive skylight polarized orientation method for high dynamic range (HDR) scenes. Initially, we built a model of the image acquisition pipeline that can recover HDR irradiance maps from polarization images. Subsequently, the orientation method was designed based on a combination of the irradiance maps and the least squares methods. Some preprocessing steps were utilized to eliminate occlusion interference. In addition, an autoexposure adjustment method was proposed using information entropy and heuristic segmentation. Finally, the experimental results show that the proposed method can improve the accuracy of bionic orientation and adaption to skylight with occlusions and interference in natural conditions.

Investigating Bio-Inspired Approaches for Designing Psycho-Oncological Support Units in Egypt

Investigating Bio-Inspired Approaches for Designing Psycho-Oncological Support Units in Egypt

Bioinspired Sandcastle Worm-Derived Peptide-Based Hybrid Hydrogel for Promoting the Formation of Liver Spheroids.

The generation of hepatic spheroids is beneficial for a variety of potential applications, including drug development, disease modeling, transplantation, and regenerative medicine. Natural hydrogels are obtained from tissues and have been widely used to promote the growth, differentiation, and retention of specific functionalities of hepatocytes. However, relying on natural hydrogels for the generation of hepatic spheroids, which have batch to batch variations, may in turn limit the previously mentioned potential applications. For this reason, we researched a way to establish a three-dimensional (3D) culture system that more closely mimics the interaction between hepatocytes and their surrounding microenvironments, thereby potentially offering a more promising and suitable system for drug development, disease modeling, transplantation, and regenerative medicine. Here, we developed self-assembling and bioactive hybrid hydrogels to support the generation and growth of hepatic spheroids. Our hybrid hydrogels (PC4/Cultrex) inspired by the sandcastle worm, an Arg-Gly-Asp (RGD) cell adhesion sequence, and bioactive molecules derived from Cultrex BME (Basement Membrane Extract). By performing optimizations to the design, the PC4/Cultrex hybrid hydrogels can enhance HepG2 cells to form spheroids and express their molecular signatures (e.g., Cyp3A4, Cyp7a1, A1at, Afp, Ck7, Ck1, and E-cad). Our study demonstrated that this hybrid hydrogel system offers potential advantages for hepatocytes in proliferating, differentiating, and self-organizing to form hepatic spheroids in a more controllable and reproducible manner. In addition, it is a versatile and cost-effective method for 3D tissue cultures in mass quantities. Importantly, we demonstrate that it is feasible to adapt a bioinspired approach to design biomaterials for 3D culture systems, which accelerates the design of novel peptide structures and broadens our research choices on peptide-based hydrogels.

MPPTM: A Bio-Inspired Approach for Online Path Planning and High-Accuracy Tracking of UAVs.

The path planning and tracking problem of the multi-robot system (MRS) has always been a research hotspot and applied in various fields. In this article, a novel multi-robot path planning and tracking model (MPPTM) is proposed, which can carry out online path planning and tracking problem for multiple mobile robots. It considers many issues during this process, such as collision avoidance, and robot failure. The proposed approach consists of three parts: a neural dynamic path planner, a hyperbolic tangent path optimizer, and an error-driven path tracker. Assisted by Ultra-wideband positioning system, the proposed MPPTM is a low-cost solution for online path planning and high-accurate tracking of MRS in practical environments. In the proposed MPPTM, the proposed path planner has good time performance, and the proposed path optimizer improves tracking accuracy. The effectiveness, feasibility, and better performance of the proposed model are demonstrated by real experiments and comparative simulations.

Ultrasonic green synthesis of silver nanoparticles mediated by Pectin: Characterization and evaluation of the cytotoxicity, antioxidant, and colorectal carcinoma properties

Regarding applicative, facile, green chemical research, a bio-inspired approach is being reported for the synthesis of Ag nanoparticles by pectin as a natural reducing and stabilizing agent without using any toxic and harmful reagent. The biosynthesized Pectin/Ag NPs were characterized by advanced physicochemical techniques like ultraviolet–visible (UV–Vis), Fourier Transformed Infrared spectroscopy (FT-IR), Scanning Electron Microscopy (SEM), High-Resolution Transmission Electron Microscopy (HR-TEM), Energy Dispersive X-ray spectroscopy (EDX), and X-ray Diffraction (XRD) study. It has been established that pectin-stabilized silver nanoparticles have a spherical shape with a mean diameter from 15 to 20 nm. After that, the biological performance of those biomolecules functionalized Ag NPs was investigated. In the MTT assay, human colorectal carcinoma (HCT-8 [HRT-18], Ramos.2G6.4C10, HT-29, and HCT 116) and normal cell lines (HUVEC) were used to study the cytotoxicity and anticancer potential of human colorectal over the AgNO 3 and Pectin/Ag NPs. The cell viability of Pectin/Ag NPs was very low against human colorectal carcinoma cell lines without any cytotoxicity on the normal (HUVEC) cell line. The best anti-human colorectal carcinoma properties of Pectin/Ag NPs against the above cell lines was in the case of the HCT 116 cell line. The antioxidant properties of the AgNO 3 and Pectin/Ag NPs were calculated against DPPH free radicals. The IC50 of Pectin/Ag NPs was 167 µg/mL. According to the above results, the Pectin/Ag NPs may be administrated to treat human colorectal carcinoma in humans.

Nanopillar Templating Augments the Stiffness and Strength in Biopolymer Films.

Natural load-bearing mammalian tissues, such as cartilage and ligaments, contain ∼70% water yet can be mechanically stiff and strong due to the highly templated structures within. Here, we present a bioinspired approach to significantly stiffen and strengthen biopolymer hydrogels and films through the combination of nanoscale architecture and templated microstructure. Imprinted submicrometer pillar arrays absorb energy and deflect cracks. The produced chitosan hydrogels show nanofiber chains aligned by nanopillar topography, subsequently templating the microstructure throughout the film. These templated nanopillar chitosan hydrogels mechanically outperform unstructured flat hydrogels, with increases in the moduli of ∼160%, up to ∼20 MPa, and work at break of ∼450%, up to 8.5 MJ m-3. Furthermore, the strength at break increases by ∼350%, up to ∼37 MPa, and it is one of the strongest hydrogels yet reported. The nanopillar templating strategy is generalizable to other biopolymers capable of forming oriented domains and strong interactions. Overall, this process yields hydrogel films that demonstrate mechanical performance comparable to that of other stiff, strong hydrogels and natural tissues.