Enhancing strength and toughness of cellulose nanofibril network structures with an adhesive peptide

An Ultrastrong and Ultraflexible Wood Veneer via Fiber Interaction Enhancement and Defect Reduction

Natural wood veneer is a flexible and sustainable material with significant potential for various applications. However, there are more defects in wood veneer, leading to lower strength, and the strengthening strategies currently used for wood blocks do not work well when applied to wood veneer. In this study, we processed the fragile wood veneer into an ultrastrong and ultraflexible material with a tensile strength of 578.4 MPa and preserved its beautiful wood texture. This enhancement is achieved by reducing defects within the veneer through adding cellulose molecules between the wood cell fibers. The resulting wood veneer is exceedingly flexible compared to natural wood, with a bending radius as small as 0.2 mm, while retaining its strength. This flexibility allows the veneer to be wrapped around other materials and improves the mechanical properties. The wood veneer exhibits much lower signal attenuation compared to carbon fiber fabric composites due to its electromagnetic transparency. Moreover, the environmental impact of producing each kilogram of this veneer is less than that of the carbon fiber material. These ultrastrong, ultraflexible, and sustainable properties of the wood veneer can enrich the family of lightweight, high-strength materials and enable a wide range of applications.

Optimization and addition of bagasse Dialdehyde Carboxymethyl cellulose (DCMC) as a crosslinking agent for improving the ternary biopolymer blended films: Rice starch, chitosan, and Sericin properties

The development of a ternary biopolymer blended films incorporating rice starch (RS), chitosan (CH), and sericin (SC) crosslinked with dialdehyde carboxymethyl cellulose (DCMC) from bagasse was investigated. The biopolymer films were prepared through a solution casting method, with varying DCMC concentrations (0-0.2 % (w/v)). The physical, mechanical, and thermal properties of the films were evaluated, including thickness, color difference, moisture absorption, solubility, tensile strength, elongation at break, and heat-sealing strength. The results informed that increasing of DCMC content improved the tensile strength and reduced elongation at break, indicating enhanced crosslinking between polysaccharide based and protein-based biopolymers. The film with 0.2 % (w/v) DCMC exhibited the highest tensile strength (3.36 MPa) and lowest (w/v) DCMC. Fourier-transform infrared spectroscopy (FTIR) confirmed the formation of Schiff's base between DCMC and the biopolymers, contributing to the improved mechanical properties. Thermogravimetric analysis (TGA) demonstrated enhanced thermal stability with higher DCMC content. The study concludes that DCMC is an effective crosslinking agent for enhancing the properties of RS/CH/SC biopolymer films, making them suitable for sustainable food packaging applications.

Natural biomaterials for sustainable flexible neuromorphic devices

Neuromorphic electronics use neural models in hardware to emulate brain-like behavior, and provide power-efficient, extremely compact, and massively-parallel processing, so they are ideal candidates for next-generation information-processing units. However, traditional rigid neuromorphic devices are limited by their unavoidable mechanical and geometrical mismatch with human tissues or organs. At the same time, the rapid development of these electronic devices has generated a large amount of electronic waste, thereby causing severe ecological problems. Natural biomaterials have mechanical properties compatible with biological tissues, and are environmentally benign, ultra-thin, and lightweight, so use of these materials can address these limitations and be used to create next-generation sustainable flexible neuromorphic electronics. Here, we explore the advantages of natural biomaterials in simulating synaptic behavior of sustainable neuromorphic devices. We present the flexibility, biocompatibility, and biodegradability of these neuromorphic devices, and consider the potential applicability of these properties in wearable and implantable bioelectronics. Finally, we consider the challenges of device fabrication and neuromorphic system integration by natural biomaterials, then suggest future research directions.

Designing Short Cardin-Motif Peptide and Biopolymer-Based Multicomponent Hydrogels for Developing Advanced Composite Scaffolds for Improving Cellular Behavior

Multicomponent self-assembly represents a cutting-edge strategy in peptide nanotechnology, enabling the creation of nanomaterials with enhanced physical and biological characteristics. This approach draws inspiration from the highly complex nature of the native extracellular matrix (ECM) constituting multicomponent biomolecular entities. In recent years, the combination of bioactive peptide with polymer has gained significant attention for the fabrication of novel biomaterials due to their inherent specificity, tunable physiochemical properties, biocompatibility, and biodegradability. This advanced strategy can address the limitation of the lower mechanical strength of the individual peptide hydrogel by incorporating the biopolymer, resulting in the formation of a composite scaffold. In this direction, this advanced strategy is explored using noncovalent interactions between cellulose nano-fiber (CNF) and cationic Cardin-motif peptide to develop advanced composite scaffolds. The bioactive cationic peptide otherwise failed to form hydrogel at physiological conditions. Interestingly, the differential mixing ratio of CNF and peptide modulated the surface charge, functionality, and mechanical properties of the composite scaffolds, resulting in diverse cellular responses. 10:1 (w/w) ratio of CNF and peptide-based composite scaffold demonstrates improved cellular survival and proliferation in 2D culture conditions. Notably, in 3D cultures, cell proliferation on the 10:1 matrix is comparable to Matrigel, highlighting its potential for advanced tissue engineering applications.

Nanocellulose-short peptide self-assembly for improved mechanical strength and barrier performance

Cellulose nanofibers (CNF) are the most abundant renewable nanoscale fibers on Earth, and their use in the design of hybrid materials is ever more acclaimed, although it has been mostly limited, to date, to CNF derivatives obtained via covalent functionalization. Herein, we propose a noncovalent approach employing a set of short peptides - DFNKF, DF(I)NKF, and DF(F5)NKF - as supramolecular additives to engineer hybrid hydrogels and films based on unfunctionalized CNF. Even at minimal concentrations (from 0.1% to 0.01% w/w), these peptides demonstrate a remarkable ability to enhance CNF rheological properties, increasing both dynamic moduli by more than an order of magnitude. Upon vacuum filtration of the hydrogels, we obtained CNF-peptide films with tailored hydrophobicity and surface wettability, modulated according to the peptide content and halogen type. Notably, the presence of fluorine in the CNF-DF(F5)NKF film, despite being minimal, strongly enhances CNF water vapor barrier properties and reduces the film water uptake. Overall, this approach offers a modular, straightforward method to create fully bio-based CNF-peptide materials, where the inclusion of DFNKF derivatives allows for facile functionalization and material property modulation, opening their potential use in the design of packaging solutions and biomedical devices.

Mechanically Robust Biopolymer Optical Fibers with Enhanced Performance in the Near-Infrared Region

Polymer optical fibers (POFs) are lightweight, fatigue-tolerant, and suitable for local area networks, automobiles, aerospace, smart textiles, supercomputers, and servers. However, commercially available POFs are exclusively fabricated using synthetic polymers derived from nonrenewable resources. Recently, attempts have been made to fabricate biocompatible and biopolymeric optical fibers. However, their limitations in mechanical performance, thermal stability, and optical properties foil practical applications in waveguiding. Here, we report a comprehensive study of the preparation of biopolymer optical fibers with tailored mechanical strength, thermal properties, and their short-distance applications. Specifically, we use alginate as one of the key components with methylcelluloses to promote readily scalable wet spinning at ambient conditions to fabricate 21 combinations of composite fibers. The fibers display high maximum strain (up to 58%), Young's modulus (up to 11 GPa), modulus of toughness (up to 63 MJ/m3), and a high strength (up to 195 MPa), depending on the composition and fabrication conditions. The modulus of toughness is comparable to that of glass optical fibers, while the maximum strain is nearly 15 times higher. The mechanically robust fibers with high thermal stability allow rapid humidity, touch sensing, and complex shapes such as serpentine, coil, or twisted structures without losing their light transmission properties. More importantly, the fibers display enhanced optical performance and sensitivity in the near-infrared (NIR) region, making them suitable for advanced biomedical applications. Our work suggests that biobased materials offer innovative solutions to create short-distance optical fibers from fossil fuel-free resources with novel functionalities.

Cationic cellulose nanocrystals as sustainable green material for multi biological applications via ξ potential

The present study aims to disclose the activity of cationic cellulose nanocrystals (CNCs) as a promising multifunctional green nanomaterial with applications in biological aspects. The basic reason behind multifunctional behavior is zeta potential and size distribution of nano biopolymers; exhibit a remarkable physical and biological activity compared to normal molecules.The preliminary characterized studied using absorption spectral analysis showed strong absorption peak indicating that spectrum curves can be screen by UV spectra at wavelength range 200-400nm. Ultrastructural studies (SEM-EDS and TEM), manifest that CNCs are elliptical particles in shape. Also, TEM show CNCs are the ideal illustration of zero-dimensional (0-D) NPs, less than 5.1 nm in diameter with Cationic charge and similar results in size distribution by TEM. Nonetheless, developed as antioxidant activity IC₅₀ was 1467 ± 25.9 µg/mL, antimicrobial activity tested G^-ve strains, but not affected on tested G^+ve strains and tested fungi. Evaluating toxicity effect of cationic CNCs against human blood erythrocytes (RBCs) and Lymphocyte Proliferation and the end point evaluate by comet assay, which proven no cytotoxic effect. Also, a high dose 500 µg/mL of CNCs highly significant (p < 0.05) reduction in cell viability of Caco-2 cancer cells after 24 h. incubation time, whereas the IC₅₀ was 1884 ± 19.46 µg/mL. Moreover, genotoxic assay indicates Caco-2 cells cause apoptosis with no fragmentation in DNA. Undoubtedly, the obtained results brought about by the interaction of layers carrying opposing charges. Additionally, there is a balance between hydrophilic contact and electrostatic attraction. That emphasizes how the cationic CNCs have excellent potential for use as antioxidants, antimicrobials, and anticancer agents.

Exploring the TEMPO-Oxidized Nanofibrillar Cellulose and Short Ionic-Complementary Peptide Composite Hydrogel as Biofunctional Cellular Scaffolds

Multicomponent self-assembly is an emerging approach in peptide nanotechnology to develop nanomaterials with superior physical and biological properties. Inspired by the multicomponent nature of the native extracellular matrix (ECM) and the well-established advantages of co-assembly in the field of nanotechnology, we have attempted to explore the noncovalent interactions among the sugar and peptide-based biomolecular building blocks as an approach to design and develop advanced tissue scaffolds. We utilized TEMPO-oxidized nanofibrillar cellulose (TO-NFC) and a short ionic complementary peptide, Nap-FEFK, to fabricate highly tunable supramolecular hydrogels. The differential doping of the peptide into the TO-NFC hydrogel was observed to tune the surface hydrophobicity, microporosity, and mechanical stiffness of the scaffold. Interestingly, a differential cellular response was observed toward composite scaffolds with a variable ratio of TO-NFC versus Nap-FEFK. Composite scaffolds having a 10:1 (w/w) ratio of TO-NFC and the Nap-FEFK peptide showed enhanced cellular survival and proliferation under two-dimensional cell culture conditions. More interestingly, the cellular proliferation on the 10:1 matrix was found to be similar to that of Matrigel in three-dimensional culture conditions, which clearly indicated the potential of these hydrogels in advanced tissue engineering applications. Additionally, these composite hydrogels did not elicit any significant inflammatory response in Raw cells and supported their survival and proliferation, which further emphasized their ability to form versatile scaffolds for tissue regeneration. This multicomponent assembly approach to construct biomolecular composite hydrogels to access superior physical and biological properties within the scaffold is expected to improve the scope for designing novel ECM-mimicking biomaterials for regenerative medicine.

Rheological properties of wood/bacterial cellulose and chitin nano-hydrogels as a function of concentration and their nano-films properties

In this study, rheological properties of the Wood Cellulose NanoFibers (WCNF), Bacterial Cellulose NanoFibers (BCNF), and Chitin NanoFibers (ChNF) as well as physical properties of films prepared from each nano‐hydrogel were investigated. Each nano‐hydrogel was prepared in 2 concentrations of 0.5 and 1 wt% for rheological study. Rheological properties were measured using a rotational rheometer. The flow behaviour data were fitted with rheological models. Apparent viscosity was higher in higher concentrations of nano‐hydrogels. Herschel‐Bulkley model was the best model for flow behaviour data fitting. BCNF nano‐hydrogels had the highest hysteresis loop while WCNF nano‐hydrogels had the best structure recovery and lowest hysteresis loop. At LVE (Linear Viscoelastic Region), G′ (storage modulus) and G″ (loss modulus) had a constant value, but as strain increased their values decreased. Storage modulus was found to be greater than loss modulus in all samples during frequency sweep test. BCNF nano‐hydrogel showed the lowest frequency dependency. Chitin nanofilms had the highest elongation and stress value.

Developing fibrillated cellulose as a sustainable technological material

Cellulose is the most abundant biopolymer on Earth, found in trees, waste from agricultural crops and other biomass. The fibres that comprise cellulose can be broken down into building blocks, known as fibrillated cellulose, of varying, controllable dimensions that extend to the nanoscale. Fibrillated cellulose is harvested from renewable resources, so its sustainability potential combined with its other functional properties (mechanical, optical, thermal and fluidic, for example) gives this nanomaterial unique technological appeal. Here we explore the use of fibrillated cellulose in the fabrication of materials ranging from composites and macrofibres, to thin films, porous membranes and gels. We discuss research directions for the practical exploitation of these structures and the remaining challenges to overcome before fibrillated cellulose materials can reach their full potential. Finally, we highlight some key issues towards successful manufacturing scale-up of this family of materials.

Versatile Application of Nanocellulose: From Industry to Skin Tissue Engineering and Wound Healing

Nanocellulose is cellulose in the form of nanostructures, i.e., features not exceeding 100 nm at least in one dimension. These nanostructures include nanofibrils, found in bacterial cellulose; nanofibers, present particularly in electrospun matrices; and nanowhiskers, nanocrystals, nanorods, and nanoballs. These structures can be further assembled into bigger two-dimensional (2D) and three-dimensional (3D) nano-, micro-, and macro-structures, such as nanoplatelets, membranes, films, microparticles, and porous macroscopic matrices. There are four main sources of nanocellulose: bacteria (Gluconacetobacter), plants (trees, shrubs, herbs), algae (Cladophora), and animals (Tunicata). Nanocellulose has emerged for a wide range of industrial, technology, and biomedical applications, namely for adsorption, ultrafiltration, packaging, conservation of historical artifacts, thermal insulation and fire retardation, energy extraction and storage, acoustics, sensorics, controlled drug delivery, and particularly for tissue engineering. Nanocellulose is promising for use in scaffolds for engineering of blood vessels, neural tissue, bone, cartilage, liver, adipose tissue, urethra and dura mater, for repairing connective tissue and congenital heart defects, and for constructing contact lenses and protective barriers. This review is focused on applications of nanocellulose in skin tissue engineering and wound healing as a scaffold for cell growth, for delivering cells into wounds, and as a material for advanced wound dressings coupled with drug delivery, transparency and sensorics. Potential cytotoxicity and immunogenicity of nanocellulose are also discussed.

Preparation and properties of cellulose nanocrystals, gelatin, hyaluronic acid composite hydrogel as wound dressing

Gelatin (GA), hyaluronic acid (HA) and cellulose nanocrystals (CNC) are promising materials for skin wound care. In this study the GA-HA-CNC hydrogels were prepared by cross-linking and freeze-drying. The composition and mechanism of GA-HA-CNC hydrogels were confirmed by FTIR. The morphology and pore size were obtained by SEM. We accessed the physical property from rheological results and swelling ratio. NIH-3T3 cells were inoculated into the hydrogels and cultured for different days, then we analyzed the cytotoxicity of the prepared hydrogels by CCK-8 methods and live/dead pictorial diagram using staining kits. FTIR revealed the combination between GA, HA and CNC was attributed to the amide bond and hydrogen bonding. SEM results showed that the drying GA-HA-CNC hydrogels were spongy, with the pore diameter about 80-120 µm. CNC significantly enhanced the property of the hydrogels and play a vital role according to the rheology and swelling results. The cells culture results showed that NIH-3T3 cells can attached to, grow, and proliferate well on the GA-HA-CNC hydrogels. In conclusion, the natural GA-HA-CNC hydrogel has great potential for the skin wound repair.