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Gallium (Ga), a low‐melting‐point liquid metal with soft, metallic, and biocompatible properties, offers many possibilities. However, the potential of composites that integrate Ga with biomacromolecules, combining their biocompatibility, elasticity, and conductivity, has not been thoroughly explored, which is a gap for advancing these composites in various applications. In parallel and independently, protein self‐assembled l.,;3bhnanofibrils have attracted great interest as building blocks for functional biomaterials. Here, composites of Ga droplets and nanofibrils are presented, self‐assembled from plant proteins of soy protein isolate (SPI). It is evidenced that in these composites self‐assembled SPI nanofibrils can effectively reduce the oxidation of Ga droplets. It is observed that the composites of β‐sheet nanofibrils and Ga droplets offer mechanical properties similar to only fibrils‐based films. Films of 32 wt% Ga in SPI showed enhanced electrical conductivity and well‐structured nanofibrils with multifunctional potential in gas‐sensing and electronically controlled antibacterial applications. It is illustrated that the 32 wt% Ga in SPI composite offered the best sensing performance for a diatomic molecule, CO, and electro‐stimulation of this composite effectively reduced bacterial growth. The Ga in SPI composite, combining the advantages of protein nanofibrils and Ga droplets, offers great potential in future biomedical applications. [ABSTRACT FROM AUTHOR]

The application of modifying nanoadditives in the technology of cement composites is currently a relevant and widely researched topic in global materials science. The purpose of this study was to investigate new nanoadditives—nanofibrils made from synthesized wollastonite (NF) and nanospheres from corundum (NS)—produced by LLC NPK Nanosystems (Rostov-on-Don, Russia) as a modifying additive. During the experimental investigations, the mechanical properties of cement pastes and concrete were examined. This included an analysis of the density, compressive and bending strength, as well as water absorption of concrete that had been modified with NF and NS additives. X-ray phase and microstructural analyses of concrete were performed. It was established that modification of cement composites with NF and NS additives had a beneficial effect on their properties, and the optimal amount for both types of additives was 0.3% by binder weight. The highest recorded enhancements in compressive and flexural strength of concrete with 0.3% NF were 7.22% and 7.04%, respectively, accompanied by a decrease in water absorption by 4.70%. When modifying concrete with 0.3% NS, the increases in compressive and flexural strength were 2.71% and 2.48%, and water absorption decreased by 1.96%. Modification of concrete with NF and NS additives did not have a significant effect on the change in concrete density, which was no more than 1%. Based on the results of phase analysis, it was established that concrete with NF and NS additives were characterized by the presence of five main phases: quartz, portlandite, calcite, larnite, and olivine-Ca. It was found that compositions with 0.3% NF and NS differed from the control composition by the presence of such a phase as olivine-Ca. Microstructural analysis confirmed the effectiveness of NF and NS additives. The microstructure of the modified concretes was distinguished by the extensive occurrence of clusters composed of calcium silicate hydrate zones. The conducted studies prove the possibility of using NF and NS as modifying nanoadditives in the technology of cement composites. The addition of nanofibrils from synthesized wollastonite is the most effective and promising and is recommended for use in real construction practice. [ABSTRACT FROM AUTHOR]

Cribellate silks, produced by ancient spiders, are fascinating because they feature a highly sophisticated, 3D hierarchical structure consisting of filaments with different diameters and shapes. Here, the smallest and thinnest constituents of the cribellate silk are investigated: nanofibrils that form a dense mesh that is supported by larger fibers. Analysis of their structure via atomic force and transmission electron microscopies shows that they are flattened fibrils, only ≈5 nm thick — thinner than any other natural spider silk fibrils previously reported. In this work, the first mechanical tensile testing experiments on these fibrils are carried out, which reveals that the fibrils show an outstanding extensibility of at least 1100%, almost twice as much as the most stretchable spider silk previously reported. Based on these extraordinary findings, this work significantly expands the parameter space of materials properties attainable by spider silks and provides further insights into their nanomechanics. [ABSTRACT FROM AUTHOR]

Collagen is one main component of the extracellular matrix (ECM) in natural tissues and is, therefore, well suited as a biomaterial for tissue engineering. In this study, a method is presented to 3D‐bioprint collagen into a precipitation bath comprising recombinantly produced spider silk protein eADF4(C16) yielding a composite with excellent mechanical properties. The spider silk precipitation bath induced assembly of the collagen into fibrils, and subsequent addition of potassium phosphate buffer lead to the formation of silk particles and stabilization of the collagen fibrils. The produced collagen‐silk composite scaffolds show an internal structure of homogeneously distributed and interacting collagen fibrils and spider silk particles with significantly better mechanical properties compared to plain collagen scaffolds. Further, enzymatic degradation assays of the scaffolds over a 7‐day period show higher stability of the collagen‐silk scaffolds compared to plain collagen scaffolds in the presence of wound proteases. Using the spider silk variant eADF4(C16‐RGD) further increases compressive stress and elastic modulus compared to that of the unmodified variant. Finally, it is shown that the unique collagen‐spider silk composite scaffolds comprising the cell‐binding domains of collagen and the RGD sequence in the spider silk variant represent a promising material for soft tissue regeneration. [ABSTRACT FROM AUTHOR]

Abstract Oil palm trunk (OPT) is an inexpensive, abundantly available by-product of palm oil production which is typically not put to material use. Due to its comparably high cellulose content, OPT represents a suitable raw material for the preparation of cellulose nanofibrils (CNFs). Aiming for full utilization of the raw material and minimized energy demand, non-delignified and partially delignified (alkali-pretreated) OPT was subjected to mechanical fibrillation in the present study. As compared to CNFs from fully delignified OPT, the lignin-rich microfibrils obtained by this approach generally showed higher average fibril diameters, lower thermal stability as well as lower viscosity, and higher sedimentation rate in suspension. However, the combination of alkali-pretreatment and fibrillation by disc-grinding and subsequent high-pressure homogenization resulted in fibrils with properties similar to those of CNFs from fully delignified OPT. As proven by IR-spectroscopy, thermogravimetry and chemical composition analysis, alkali-treated OPT fibrils still contained substantial amounts of residual lignin which could, for instance, act as a natural coupling agent or binder in composite applications. Moreover, the facile delignification process applied herein requires far less chemicals and energy than conventional pulping and is thus beneficial from both the economic and ecological perspective.

Smart conversion of supramolecular structures in vivo is an attractive strategy in cancer nanomedicine, which is usually achieved via specific peptide sequences. Here we developed a lysosomal targeting small-molecule conjugate, PBC, which self-assembles into nanoparticles at physiological pH and smartly converts to nanofibrils in lysosomes of tumor cells. Such a transformation mechanically leads to lysosomal dysfunction, autophagy inhibition, and unusual cytoplasmic vacuolation, thus granting PBC a unique anticancer activity as a monotherapy. Importantly, the photo-activated PBC elicits significant phototoxicity to lysosomes and shows enormous advantages in overcoming autophagy-caused treatment resistance frequently occurring in conventional phototherapy. This improved phototherapy achieves a complete cure of oral cancer xenografts upon limited administration. Our work provides a new paradigm for the construction of nonpeptide nanotransformers with biomedical activities.

Epigenetic modifications play a significant role in cancer progression, making them potential targets for therapy. Histone deacetylase inhibitors have shown promise in inhibiting cancer cell growth, including in breast cancer (BC). In this research, we examined the potential of using suberoyl anilide hydroxamic acid (SAHA)‐loaded β‐lg nanofibrils as a drug delivery system for triple‐negative BC cell lines. We assessed their impact on cell cycle progression, apoptosis, levels of reactive oxygen species, and mitochondrial membrane potential in cancer cells. The combination of SAHA and β‐lg nanofibrils demonstrated enhanced efficacy in inhibiting cell growth, inducing cell cycle arrest, and promoting apoptosis (43.78%) compared to SAHA alone (40.09%). Moreover, it effectively targeted cancer cells without promoting drug resistance while using a low concentration of the nanofibrils. These findings underscore the promising potential of nanofibril‐based drug delivery systems for BC treatment. [ABSTRACT FROM AUTHOR]

The application of modifying nanoadditives in the technology of cement composites is currently a relevant and widely researched topic in global materials science. The purpose of this study was to investigate new nanoadditives—nanofibrils made from synthesized wollastonite (NF) and nanospheres from corundum (NS)—produced by LLC NPK Nanosystems (Rostov-on-Don, Russia) as a modifying additive. During the experimental investigations, the mechanical properties of cement pastes and concrete were examined. This included an analysis of the density, compressive and bending strength, as well as water absorption of concrete that had been modified with NF and NS additives. X-ray phase and microstructural analyses of concrete were performed. It was established that modification of cement composites with NF and NS additives had a beneficial effect on their properties, and the optimal amount for both types of additives was 0.3% by binder weight. The highest recorded enhancements in compressive and flexural strength of concrete with 0.3% NF were 7.22% and 7.04%, respectively, accompanied by a decrease in water absorption by 4.70%. When modifying concrete with 0.3% NS, the increases in compressive and flexural strength were 2.71% and 2.48%, and water absorption decreased by 1.96%. Modification of concrete with NF and NS additives did not have a significant effect on the change in concrete density, which was no more than 1%. Based on the results of phase analysis, it was established that concrete with NF and NS additives were characterized by the presence of five main phases: quartz, portlandite, calcite, larnite, and olivine-Ca. It was found that compositions with 0.3% NF and NS differed from the control composition by the presence of such a phase as olivine-Ca. Microstructural analysis confirmed the effectiveness of NF and NS additives. The microstructure of the modified concretes was distinguished by the extensive occurrence of clusters composed of calcium silicate hydrate zones. The conducted studies prove the possibility of using NF and NS as modifying nanoadditives in the technology of cement composites. The addition of nanofibrils from synthesized wollastonite is the most effective and promising and is recommended for use in real construction practice.

Silk nanofibers (SNF) have great applications in high-performance functional nanocomposites due to their excellent mechanical properties, biocompatibility, and degradability. However, the preparation of SNF by traditional methods often requires the use of some environmentally harmful or toxic reagents, limiting its application in green chemistry. In this paper, we successfully prepared SNF using natural silk as raw material and solvent stripping technology by adjusting the solvent concentration and solution ratio (the diameter of about 120 nm). Using the above SNFs as raw materials, SNF membranes were prepared by vacuum filtration technology. In addition, we prepared an SNF/MXene nanocomposite material with excellent humidity sensitivity by simply coating MXene nanosheets with silk fibers. The conductivity of the material can approach 1400.6 S m−1 with excellent mechanical strength (51.34 MPa). The SNF/MXene nanocomposite material with high mechanical properties, high conductivity, and green degradability can be potentially applied in the field of electromagnetic interference (EMI) shielding, providing a feasible approach for the development of functional nanocomposite materials. [ABSTRACT FROM AUTHOR]

The objective of this work was to investigate the effect of the addition of a nanocellulose gel from cocoa bean husk (NAC) on nanocellulose gels of Eucalyptus sp. and Pinus sp. The nanogels were obtained by mechanical defibrillation and the films by casting with different concentrations of NAC (0%, 20% and 35%). These were evaluated for morphology, thermogravimetric properties, barrier properties and soil biodegradability. NAC fibres presented the shortest lengths (30–80 µm), and their addition to the films reduced degradation at 350 °C by 17% but did not cause changes in water vapor permeability. NAC increased the solubility and biodegradability of the films, especially those of Eucalyptus sp. (35%). Therefore, the use of NAC proved to be a promising tool in the formulation of biodegradable packaging. [ABSTRACT FROM AUTHOR]

Spider silk is biocompatible, biodegradable, and rivals some of the best synthetic materials in terms of strength and toughness. Despite extensive research, comprehensive experimental evidence of the formation and morphology of its internal structure is still limited and controversially discussed. Here, we report the complete mechanical decomposition of natural silk fibers from the golden silk orb-weaver Trichonephila clavipes into ≈10 nm-diameter nanofibrils, the material's apparent fundamental building blocks. Furthermore, we produced nanofibrils of virtually identical morphology by triggering an intrinsic self-assembly mechanism of the silk proteins. Independent physico-chemical fibrillation triggers were revealed, enabling fiber assembly from stored precursors "at-will". This knowledge furthers the understanding of this exceptional material's fundamentals, and ultimately, leads toward the realization of silk-based high-performance materials. Spider silk is one of the strongest and toughest biomaterials, rivaling the best man-made materials. The origins of these traits are still under debate but are mostly attributed to the material's intriguing hierarchical structure. Here we fully disassembled spider silk into 10 nm-diameter nanofibrils for the first time and showed that nanofibrils of the same appearance can be produced via molecular self-assembly of spider silk proteins under certain conditions. This shows that nanofibrils are the key structural elements in silk and leads toward the production of high-performance future materials inspired by spider silk. [Display omitted] [ABSTRACT FROM AUTHOR]

An engineered 3D architectural network of the biopolymeric hydrogel can mimic the native cell environment that promotes cell infiltration and growth. Among several bio-fabricated hydrogel structures, core–shell microcapsules inherit the potential of cell encapsulation to ensure the growth and transport of cells and cell metabolites. Herein, a co-axial electrostatic encapsulation strategy is used to create and encapsulate the cells into chitin nanofibrils integrated alginate hydrogel microcapsules. Three parameters that are critical in the electrostatic encapsulation process, hydrogel composition, flow rate, and voltage were optimized. The physicochemical characterization including structure, size, and stability of the core–shell microcapsules was analyzed by scanning electron microscope (SEM), FTIR, and mechanical tests. The cellular responses of the core–shell microcapsules were evaluated through in vitro cell studies by encapsulating NIH/3T3 fibroblast cells. Notably, the bioactive microcapsule showed that the cell viability was found excellent for more than 2 weeks. Thus, the results of this core–shell microcapsule showed a promising approach to creating 3D hydrogel networks suitable for different biomedical applications such as in vitro tissue models for toxicity studies, wound healing, and tissue repair. [ABSTRACT FROM AUTHOR]

Introduction: Oxyntomodulin (Oxm) hormone peptide has a number of beneficial effects on nutrition and metabolism including increased energy expenditure and reduced body weight gain. Despite its many advantages as a potential therapeutic agent, Oxm is subjected to rapid renal clearance and protease degradation limiting its clinical application. Previously, we have shown that subcutaneous administration of a fibrillar Oxm formulation can significantly prolong its bioactivity in vivo from a few hours to a few days. Methods: We used a protease resistant analogue of Oxm, Aib2-Oxm, to form nanfibrils depot and improve serum stability of released peptide. The nanofibrils and monomeric peptide in solution were characterized by spectroscopic, microscopic techniques, potency assay, QCM-D and in vivo studies. Results: We show that in comparison to Oxm, Aib2-Oxm fibrils display a slower elongation rate requiring higher ionic strength solutions, and a higher propensity to dissociate. Upon subcutaneous administration of fibrillar Aib2-Oxm in rodents, a 5-fold increase in bioactivity relative to fibrillar Oxm and a significantly longer bioactivity than free Aib2-Oxm were characterized. Importantly, a decrease in food intake was observed up to 72-hour post-administration, which was not seen for free Aib2-Oxm. Conclusion: Our findings provides compelling evidence for the development of long-lasting peptide fibrillar formulations that yield extended plasma exposure and enhanced in vivo pharmacological response. [ABSTRACT FROM AUTHOR]

This chapter provides a summary of the current knowledge concerning the design, synthesis, and production of some innovative classes of nanoparticles and nanofibers, highlighting their potential use as ingredient carriers able to efficiently penetrate through the different skin layers. To this aim, the main characteristics and functions of the skin structure are described, as well as the possible mechanisms of skin penetration, outlining some disadvantages of current cosmetic emulsions. The novel carriers are made of non-woven tissues based on biodegradable nano-biopolymers and loaded with natural active ingredients, which are released at the level of the different skin layers, at the desired dose and time. By these smart tissues, it is possible to make innovative cosmeceuticals and nutraceuticals which, free of water, preservatives, emulsifiers, fragrances, colors, and other chemicals, are obtained from food and agro-forestry waste. By this new technology, able to provide carriers having the same structure as the natural extra cellular matrix (ECM), it will be possible to produce skin- and environmentally friendly products, reducing the consumption of water and natural resources, thus contributing to both human and environmental health. [ABSTRACT FROM AUTHOR]

IntroductionOxyntomodulin (Oxm) hormone peptide has a number of beneficial effects on nutrition and metabolism including increased energy expenditure and reduced body weight gain. Despite its many advantages as a potential therapeutic agent, Oxm is subjected to rapid renal clearance and protease degradation limiting its clinical application. Previously, we have shown that subcutaneous administration of a fibrillar Oxm formulation can significantly prolong its bioactivity in vivo from a few hours to a few days.MethodsWe used a protease resistant analogue of Oxm, Aib2-Oxm, to form nanfibrils depot and improve serum stability of released peptide. The nanofibrils and monomeric peptide in solution were characterized by spectroscopic, microscopic techniques, potency assay, QCM-D and in vivo studies.ResultsWe show that in comparison to Oxm, Aib2-Oxm fibrils display a slower elongation rate requiring higher ionic strength solutions, and a higher propensity to dissociate. Upon subcutaneous administration of fibrillar Aib2-Oxm in rodents, a 5-fold increase in bioactivity relative to fibrillar Oxm and a significantly longer bioactivity than free Aib2-Oxm were characterized. Importantly, a decrease in food intake was observed up to 72-hour post-administration, which was not seen for free Aib2-Oxm.ConclusionOur findings provides compelling evidence for the development of long-lasting peptide fibrillar formulations that yield extended plasma exposure and enhanced in vivo pharmacological response.

This investigation assessed the potential of bacterial cellulose (BC) in two distinct forms, nanocrystals (BC-NC) and oxidized nanofibrils (BC-NF), as stabilizers for low oil-in-water emulsions (1 % v/v). The research explored the impact of ionic strength and BC concentration on the physico-chemical characteristics, stability, and rheological properties of those emulsions. Nanofibrils had diameters ranging from 25 to 146 nm and lengths in the micrometer range, while nanocrystals varied in length from 133 to 870 nm and in diameter from 20 to 60 nm. Both BC-NF and BC-NC exhibited high zeta potential values (>−45 mV) and contact angles of 30-31°, indicating stability. Both nanocelluloses were effectively used as stabilizers in Pickering emulsions, namely in low-oil systems, producing small emulsion droplets with sizes between 1.42 and 4.13 μm. Further results revealed that ionic strength influenced emulsion stability, with both BC-NF and BC-NC preferentially located on the surfaces of emulsion droplets in the presence of salt, as demonstrated by microscopy images. The presence of BC at the interface contributed to creating a more robust barrier against coalescence and Ostwald ripening, influencing droplet size and rheological properties. Higher BC concentrations (1 %) increased emulsion stability in the absence of salt, while at lower BC concentrations (0.5 %), salt concentration was determinant for the long-term stability of the emulsions. These findings provide valuable insights into the production of Pickering emulsions using nanocelluloses, highlighting the advantages of bio-based nanomaterials for applications in the food industry. [Display omitted] • Bacterial nanocellulose acts as a stabilizer of low oil (1%) Pickering emulsions. • Nanofibrils or nanocrystals (1 %) stabilize emulsions even in the absence of NaCl. • At low nanocellulose concentrations (0.5 %), NaCl enhances emulsion stability. • Under centrifugal forces, 1% nanofibrils were able to keep emulsion's stability. • Stability and rheological properties can be controlled using nanocelluloses. [ABSTRACT FROM AUTHOR]

Organic phase change materials (PCMs) are inexpensive, safe, and do not segregate. However, they exhibit a low thermal conductivity. Several papers have reported the synthesis of organic–inorganic hybrid PCMs by adding inorganic fillers to increase the thermal conductivity. However, large amounts of fillers are needed to support the shape for the encapsulation of PCMs. Herein, we propose a facile synthesis strategy that yields composite PCMs with enhanced thermal performance. Initially, 1,3:2,4-dibenzylidene sorbitol (DBS) organogel was added as an organic filler to poly(ethylene glycol) (PEG) PCMs for maintaining the form and prevent leakage. Subsequently, a small amount of an inorganic filler, graphene nanoplatelets (GNPs), was added to these organic PCMs. Consequently, the thermal conductivity and shape stabilization of the PEG/GNPs/DBS PCMs were significantly improved. These prepared composite PCMs, with excellent shape stabilization, appropriate latent heat, and ideal thermal conductivity, are potential as fillers in solar-thermal systems and energy-efficient buildings. [ABSTRACT FROM AUTHOR]

Chitin nanofibrils (CN) can be obtained from crustaceans and fungal sources and can be used for preparing coatings for bioplastic films, that are fundamental for developing a safe and sustainable biodegradable food packaging. Coatings with different concentrations of CN from shrimps were applied on different bioplastic substrates, like Poly (butylene succinate-co-adipate)/Poly(3-hydroxybutyrate-co-3-hydroxyvalerate (PBSA/PHBV) blend, Polybutylene succinate (PBS), and Polybutylene adipate terephthalate/Poly(lactic acid) (PBAT/PLA) blend, but the adhesion to the substrates was scarce. On the contrary, the fungal-based CN showed a better adhesion. Additionally, it was found that the use of an additive based on oligomeric lactic acid was useful to prepare a coating with an improved adhesion to bioplastics. The gas barrier properties to oxygen and water vapour of coated and un-coated films were measured, revealing an improvement of these properties thanks to applied coatings, especially towards the oxygen. Antimicrobial properties and biodegradation capacity were also evaluated revealing an antibacterial effect of the coatings that did not significantly interfere with their biodegradability. The results are discussed and interpreted considering the correlation between composition and macromolecular structures with the observed functional properties. [ABSTRACT FROM AUTHOR]

Photolithography combined with surface nucleated protein self‐assembly of azido‐modified spider silk proteins is used to create an arbitrarily shaped, inherently cell repellent micropattern based on nanofibrillar networks. Using "click" chemistry with dibenzocyclooctin modified oligonucleotides, the microstructures are functionalized with DNA‐aptamers, which selectively bind cancer cell markers protein tyrosine kinase 7 or nucleolin. The epitope‐specific cell interaction on the aptamer‐modified surfaces is tested using human non‐adherend leukemia T cells (Jurkat), as well as adherent cervix carcinoma (HeLa) and neuroblastoma (Kelly) cells. The cells can be immobilized with high precision and cell densities on the pattern, also revealing spatially defined proliferation and spreading into distinct morphologies upon cultivation. The formation of integrin‐based focal adhesions occurs in the case of the aptamer immobilized cancer cells, similarly to those anchored on RGD‐modified pattern. The firm aptamer‐marker anchorage allows for the formation of integrin‐dependent cell adhesions. Due to the amenability of the recombinant spider silk protein towards chemical and genetical modifications, the presented micropatterned fibrous networks have great potential for further development of adjustable and biocompatible cell‐specific arrays, enabling applications in circulating cancer cell isolation and cultivation, studies on the cell's pathogenesis, progression and metastasis capabilities as well as enabling development of platforms for personalized medicine. [ABSTRACT FROM AUTHOR]

Due to the high aspect ratio, appealing mechanical characteristics, and various adjustable functional groups on the surface proteins, food‐grade protein nanofibrils have attracted great research interest in the field of food science. Fibrillation, known as a process of peptide self‐assembly, is recognized as a common attribute for food‐grade proteins. Converting food‐grade proteins into nanofibrils is a promising strategy to broaden their functionality and applications, such as improvement of the properties of gelling and emulsifying, especially for constructing various delivery systems for bioactive compounds. Protein source and processing conditions have a great impact on the size, structure, and morphology of nanofibrils, resulting in extreme differences in functionality. With this feature, it is possible to engineer nanofibrils into four different delivery systems, including gels, microcapsules, emulsions, and complexes. Construction of nanofibril‐based gels via multiple cross‐linking methods can endow gels with special network structures to efficiently capture bioactive compounds and extra mechanical behavior. The adsorption behavior of nanofibrils at the interface is highly complex due to the influence of several intrinsic factors, which makes it challenging to form stabilized nanofibril‐based emulsion systems. Based on electrostatic interactions, microcapsules and complexes prepared using nanofibrils and polysaccharides have combined functional properties, resulting in adjustable release behavior and higher encapsulation efficiency. The bioactive compounds delivery system based on nanofibrils is a potential solution to enhance their absorption in the gastrointestinal tract, improve their bioavailability, and deliver them to target organs. Although food‐grade protein nanofibrils show unknown toxicity to humans, further research can contribute to broadening the application of nanofibrils in delivery systems. [ABSTRACT FROM AUTHOR]

Self‐assembly of a recombinant spider silk protein into nanofibrillar networks in combination with photolithography is used to produce diversely functionalized micropattern. Amino‐modified substrates coated with a positive tone photoresist are processed into 1 µm deep arbitrarily shaped microwells, at the bottom of which spider silk proteins are covalently coupled to the deprotected aminated surface. The protein layer serves to seed the self‐assembly of nanofibrils from the same protein in the microwells, forming immobilized few nanometers thin networks after the stripping of the photoresist. The nanofibrous micropattern can be functionalized by employing fluorescently modified spider silk variants during the self‐assembly or by later covalent modification with nucleic acids. By repeating the photolithography and fibril assembly procedures, two functionally different and spatially defined pattern are created. [ABSTRACT FROM AUTHOR]

Enzymatic hydrolysis prior to fibrillation could promote the formation of soy protein isolate (SPI) nanofibrils. However, the large amount of resulting insoluble soy protein hydrolysates (ISPH) demonstrated significantly limited fibrillation capacity. In this study, the modification of ISPH through the combination of pH and ultrasound treatment significantly enhanced their solubility and further promoted fibrillation capacity. Ultrasound treatment at pH 8.0 and 2.0 significantly reduced the particle size of ISPH and enhance their ζ-potential, promoting uniform dispersion in water and improving solubility. In addition, ISPH modified by ultrasound treatment at pH 2.0 and 8.0 contributed to the formation of short, worm-like nanofibrils with characteristic cross-β structure. Ultrasound treatment (250 W) at pH 2.0 conferred the highest surface hydrophobicity (H 0 ) to ISPH, resulting in the increase (9.30 %) in the content of antiparallel β-sheets after heating for 12 h. This study provided theoretical support for the development of insoluble protein resources for manufacturing nanofibrils., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

This research aimed to develop a mupirocin-doped α-cellulose nanopaper (MDAC-NP) as a wound dressing to accelerate wound healing while limiting localized bacterial growth. The α-cellulose nanofibrils suspension was prepared by ultrasonication followed by microfluidization and subsequently doped with 0.05% w/v mupirocin to prepare nanopaper (MDAC-NP-A). The optimized batch of MDAC-NP had a porosity of 47.46 ± 0.60%, a thickness of 30 μm and a tensile strength of 0.113 MPa. The transmission electron microscopy images revealed long, slender, intertwined nanofibrillar structures and the scanning electron microscopy confirmed stable lamellar structures with tight nanofibrillar networks, giving them translucency. MDAC-NP-A had an excellent water vapor transmission rate of 2963 ± 10.26 g/m 2 /day, providing an optimal moist environment locally to promote wound healing. The mupirocin inclusion in the nanopapers was corroborated by the Fourier transform infrared spectroscopy and its crystallinity by X-ray diffraction, and differential scanning calorimetry results. The 100% drug release, was observed at 12 h from optimized MDAC-NP-A with a controlled release pattern. The MDAC-NP showed better antimicrobial activity, against S. aureus (41 mm) than E. coli (25 mm) and P. aeruginosa (17 mm) and was found to be better than marketed ointment. Thus, mupirocin-doped α-cellulose nanopapers emerge as a potential wound dressing for treating primary and secondary skin infections caused by external wounds., Competing Interests: Declarations. Ethics Approval and Consent to Participate: Not applicable. Consent for Publication: The manuscript has been read and approved by all the authors. Competing Interests: The authors report no conflict of interest., (© 2024. The Author(s), under exclusive licence to American Association of Pharmaceutical Scientists.)

Most oxidases rely on the cofactors for catalyzing the electron transfer reactions, while tend to suffer from externally-induced protein unfolding, cofactor dissociation and nonrecovery of the activities. We have previously demonstrated that the self-assembled oligohistidine peptides, without assistance of the heme cofactor, can mimic the catalytic function of the heme-dependent peroxidases that promoted H2O2 reduction reactions. Herein, we conjugate a fibril-forming peptide to the oligohistidine, to guide the self-assembly of the heme-free catalyst into amyloid-like structures, which facilitate the association of the histidine residues. The modified oligohistidine materials are able to catalyze H2O2 reduction reactions efficiently through the formation of reactive ternary complex intermediates, similar to the mechanism to the unmodified oligohistdine, but the catalytic efficiency is over one order of magnitude higher. Moreover, the catalyst can be switched between inactive and active state without loss of activity for more than ten cycles of heating/cooling treatments, and showed selective oxidation of benzidine substrates over phenolic substrates. These results may aid the future design of the robust cofactor-free supramolecular catalysts and support the evolutionary link between the primitive amyloids and modern-day enzymes.

Polysaccharides and proteins are extensively used for the design of advanced sustainable materials. Owing to the high aspect ratio and specific surface area, ease of modification, high mechanical strength and thermal stability, renewability, and biodegradability, biopolymeric nanofibrils are gaining growing popularity amongst the catalog of nanostructures exploited in a panoply of fields. These include the nanocomposites, paper and packaging, environmental remediation, electronics, energy, and biomedical applications. In this review, recent trends on the use of cellulose and protein nanofibrils as versatile substrates for the design of high-performance nanomaterials are assessed. A concise description of the preparation methodologies and characteristics of cellulosic nanofibrils, namely nanofibrillated cellulose (NFC), bacterial nanocellulose (BNC), and protein nanofibrils is presented. Furthermore, the use of these nanofibrils in the production of sustainable materials, such as membranes, films, and patches, amongst others, as well as their major domains of application, are briefly described, with focus on the works carried out at the BioPol4Fun Research Group (Innovation in BioPolymer based Functional Materials and Bioactive Compounds) from the Portuguese associate laboratory CICECO–Aveiro Institute of Materials (University of Aveiro). The potential for partnership between both types of nanofibrils in advanced material development is also reviewed. Finally, the critical challenges and opportunities for these biobased nanostructures for the development of functional materials are addressed.

An engineered 3D architectural network of the biopolymeric hydrogel can mimic the native cell environment that promotes cell infiltration and growth. Among several bio-fabricated hydrogel structures, core–shell microcapsules inherit the potential of cell encapsulation to ensure the growth and transport of cells and cell metabolites. Herein, a co-axial electrostatic encapsulation strategy is used to create and encapsulate the cells into chitin nanofibrils integrated alginate hydrogel microcapsules. Three parameters that are critical in the electrostatic encapsulation process, hydrogel composition, flow rate, and voltage were optimized. The physicochemical characterization including structure, size, and stability of the core–shell microcapsules was analyzed by scanning electron microscope (SEM), FTIR, and mechanical tests. The cellular responses of the core–shell microcapsules were evaluated through in vitro cell studies by encapsulating NIH/3T3 fibroblast cells. Notably, the bioactive microcapsule showed that the cell viability was found excellent for more than 2 weeks. Thus, the results of this core–shell microcapsule showed a promising approach to creating 3D hydrogel networks suitable for different biomedical applications such as in vitro tissue models for toxicity studies, wound healing, and tissue repair.

This study investigates how enzymatic activity (X1) and pretreated soybean straw concentration (X2) affect the production of cellulose nanofibers and reducing sugars using the Composite Central Rotational Design (CCRD). The soybean straw is subjected to alkaline pretreatment with either 5% NaOH (PT1) or 17.5% NaOH (PT2), followed by bleaching (4% H2O2) and enzymatic treatment. The mathematical model generated by Response Surface Methodology (RSM) predicts that increasing X1 and X2 simultaneously is necessary to increase the nanocellulose yield. On the other hand, to increase the sugar yield, it is necessary to increase the ratio X1:X2. The model also predicts that the lowest concentration of soybean straw (1.17%) resulted in more stable nanofiber suspensions, regardless of the enzyme activity (−25.0 and −19.4 mV for PT1 and PT2, respectively). The optimal condition for the simultaneous production of cellulose nanofibers and reducing sugars is 4.0 g of biomass and enzymatic activity of 600 CMCU, resulting for PT1 and PT2, respectively: 7.01 and 3.73 g of nanofibers/100 g of soybean straw; 11.34 and 14.30 g of reducing sugars/100 g of soybean straw. Therefore, the processing efficiency according to the pretreatment used can directly guide the production of cellulose nanofibers and reducing sugars. [ABSTRACT FROM AUTHOR]

This article presents an investigation into the effects of lignocellulose nanofibrils (LCNF) and delignified cellulose nanofibrils (DCNF) on the hydration, microstructure, and mechanical properties of cement paste. The effects of various fine contents and dosages of the cellulose nanofibrils (CNF) additions on the properties of cement paste are presented in this article. Nearly all the CNF containing batches were observed to have an accelerated cement hydration reaction within the first 30 h. However, after 80 h of hydration, the CNF additions no longer exhibited any significant effect on the degree of hydration. The cement paste batches with LCNF were observed to have improved workability compared to those with DCNF. It was further observed that the compressive and flexural strengths of the cement paste can be increased up to 20% and 111%, respectively, by the addition of CNF. Both LCNF and DCNF were found to reduce the amounts of ettringite and portlandite in the hydrated cement paste. The ideal fine content of CNF to achieve both microstructural and mechanical performance enhancement was observed to be around 75%. The experimental findings presented in this article indicate that LCNFs with low fine content (60–75%) would be a more desirable and potentially more economical additive for concrete production compared to the DCNFs with high fine contents.

Enzymatic hydrolysis prior to protein fibrillation was an effective way to facilitate the formation of nanofibrils. This study aimed to investigate the effects of molecular weights of hydrolysate on the kinetics, structures, and interactions of soy protein isolate (SPI) hydrolysate nanofibrils. The results showed that hydrolysate with molecular weight > 10 kDa showed a distinct fibrillation kinetics curve and a higher apparent rate constant (27.72) during fibrillation, indicating their vital role in determining the fibrillation. Hydrolysate with molecular weight > 10 kDa could form nanofibrils with higher radius gyration (17.11 ± 0.77 Å) due to stronger hydrophobic interaction, showing a stronger fibrillation ability. Hydrolysate with molecular weight within 5–10 kDa exhibited enhanced π-π stacking interactions during fibrillation, thereby promoting the extension of nanofibrils, and contributing to the formation of more nanofibrils. Hydrolysate with molecular weight < 5 kDa tended to randomly aggregate during fibrillation, resulting in a significant loss of cross-β structures in nanofibrils. Therefore, hydrolysate with different molecular weights exhibited synergistic effects during fibrillation. • Hydrolysate with molecular weight > 10 kDa determined the fibrillation rate. • Hydrolysate with molecular weight within 5–10 kDa promoted nanofibril formation. • Hydrolysate with molecular weight < 5 kDa tended to random aggregate. • Molecular weight affected hydrophobic interaction and π-π interaction of fibrillation. [ABSTRACT FROM AUTHOR]

[Display omitted] • A simple, eco-friendly method produced solvent-free, zero-waste NP samples. • NP spheres of PE, PP, and PS with varied sizes and distributions were fabricated. • Stretching techniques yielded NP ellipsoids and fibrils. • Water-soluble polymer blends posed a high risk of releasing MPs and NPs into the aquatic environment. Plastic pollution poses a critical global environmental challenge, and within this context, nanoplastics (NPs), the smallest plastic fragments, remain poorly understood. The progress in studying NP toxicity and developing analytical methods highly depends on access to well-defined NP materials. Herein, a straightforward and eco-friendly method for fabricating NP particles and fibrils using polymer blends as templates is presented. The process began with blending plastics with a water-soluble polymer (polyvinyl alcohol (PVA)), followed by the dissolution of the PVA matrix in water and the isolation of the NPs through a two-stage filtration process. NP materials from three widely used plastics, polyethylene, polypropylene, and polystyrene, were prepared, underscoring the versatility of this method. The resulting NPs were primarily submicron in size, and their size distribution was tuned by varying the blend ratio. Furthermore, by incorporating a stretch operation during the extrusion, the NP shape could be varied, enabling the fabrication of NP fibril materials. This method, which does not rely heavily on specialized equipment and avoids the use of harsh solvents, offers a viable and eco-friendly approach to fabricating NP samples suitable for a broad range of research applications. [ABSTRACT FROM AUTHOR]

Hydrogels formed by cellulose nanofibers (CNFs) find use in a variety of applications. CNF hydrogels generally stiffen and ultimately flocculate with increasing salt concentrations. While charge repulsion explains the behavior of nanocellulose variants that have been stabilized by charged groups, it has been a puzzle why ions have such a pronounced effect also on CNFs with unmodified surfaces. We studied the effect of ionic solutes on native CNF hydrogels, and found that already at very low concentrations of around 1 mM, ions cause crowding of the hydrogels. The ionic solutes used were NaCl, Na2SO4, NaI, NaSCN, and sodium acetate. For the hydrogels, we used low densities of CNFs which lead to relatively weak gels that were highly sensitive to salts. Screening of the electrical double layer could not explain the results at such low ion concentrations. To understand cellulose-ion interactions, we used computational molecular dynamics simulations. The results provide an explanation by the effect of ions on the structure of the hydration layers of the cellulose. Understanding how and why ions affect the properties of native CNF hydrogels can help in for example manufacture of CNFs and when using CNFs as material components, substrates for enzymes, or as rheology modifiers. Ion-effects on the hydration layer of cellulose may also be important for more fundamental understanding of interfacial interactions of cellulose with water under different conditions. [ABSTRACT FROM AUTHOR]

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Natural silk spinning is the strategy used by spiders and silkworms to construct their ultra‐strong‐and‐tough silks. It can be considered as an optimized meso‐assembly processing engineering (MAPE) strategy that effectively coordinates molecular‐and‐supramolecular assembly and native spinning. Inspired by this process, this study develops a biomimetic MAPE strategy to fabricate biomaterials mimicking the structural and mechanical characteristics of biological tissues. The structural and mechanical mimetics are realized by synergistically integrating phase transition‐induced meso‐assembly and mechanical training‐induced structural remodeling. Through this approach, highly‐hydrated silk fibroin materials with exceptional tunable mechanical properties, such as softness, high stretchability (failure strain larger than 1200%), and high strength and toughness (strength of 5 ± 1 MPa, stiffness 18 ± 2 MPa, and toughness of 6 ± 1 MJ m−3) are produced. Thanks to their structural and mechanical tissue‐matching features, these biomimetic meso‐assembled materials exhibit advances in the modulation of different cell morphologies. The gradient architecture deformation (aspect ratio, spreading area, and perimeter) is evidenced, and the interplay between cytoskeleton (actin and tubulin) and matrix adaptation orientation is substantiated. These findings advance the application of silk fibroin biomaterials in the regulation of adaptive cell reconstruction, since the morphology of cells is the basis for their physiological functions. [ABSTRACT FROM AUTHOR]

Proteins are functional building blocks of living organisms that exert a wide variety of functions, but their synthesis and industrial production can be cumbersome and expensive. By contrast, short peptides are very convenient to prepare at a low cost on a large scale, and their self-assembly into nanostructures and gels is a popular avenue for protein biomimicry. In this Review, we will analyze the last 5-year progress on the incorporation of bioactive motifs into self-assembling peptides to mimic functional proteins of the extracellular matrix (ECM) and guide cell fate inside hydrogel scaffolds. [ABSTRACT FROM AUTHOR]

Fiber morphology with off-standing branches, as found in nature, e.g., in goose downy feather, provides exquisite functions that can be barely achieved by man-made fiber systems. In this work, we develop a simple and scalable method for generating downy feather-like para-aramid fibers and assemblies. Through treating commercial para-aramid microfibers with mild alkaline solution (low concentration of NaOH), a synergistic effect of chemical hydrolysis and physical shearing is successfully triggered to generate abundant nanofiber branches on the surface of para-aramid fibers. When compared with conventional monotonous structures, nonwovens composed of downy feather-like fibers exhibit a typical multiscale fiber morphology, larger specific surface area and smaller pore size, thus showing enhanced particles adsorption capacity (over twice of the pristine nonwoven), excellent oil absorption capacity (increased by ∼ 50%), improved air filtration performances (doubled the filtration efficiency) and effective thermal insulation (thermal conductivity = 26.1 mW·m−1·K−1). More attractively, the intrinsic flame-retardant nature of para-aramid is well inherited by the downy feather-like fibers, and the fabrication process requires neither sophisticated equipment, nor tedious procedures, making us believe the strong competitiveness of these fibers and assemblies. [ABSTRACT FROM AUTHOR]

[Display omitted] Polymer with amphiphilic repeating units bathed in the mixed binary solvent can exhibit fibrillar formation and gelation via cononsolvency effect. Mechanism of gelation will be highly dependent on the solvent's interactions and morphology of the resulting fibrillar gel can be fine-tuned by changing binary solvent composition. Amphiphilic homopolymers dissolved in a mixture of two solvents with different affinities to monomeric units and to each other were modeled using dissipative particle dynamics. Morphological transitions in dilute and concentrated solutions were investigated depending on the solvent-cosolvent interaction and binary solvent composition. Fibrillar gel structure was characterized via calculation of fibril's and pore's diameters. Amphiphilic macromolecules can combine into fibrils and form a gel as a result of the cononsolvency caused by microsegregation with one or both components of a binary solvent. In the former, the fibrils are loose, in the latter - dense. For dilute solution, state diagram in terms of solvent/cosolvent miscibility and binary solvent composition is constructed and two regions with different fibrillar gels are distinguished. For concentrated solution, the conditions, governing fibrillar diameter, pore size, number and functionality of branching points, are highlighted. These findings would be useful for the controlling synthetic matrix morphologies in the tissue engineering. [ABSTRACT FROM AUTHOR]

Cellulose is the most abundant and renewable natural semicrystalline polysaccharide. This biopolymer has nanofibrillar architecture that promotes the release of free cellulose nanofibers (CNFs) and nanocrystals (CNCs). This review article describes the isolation methods, structural characteristics, properties, and potential applications of CNFs and CNCs. However, high production expenses hinder the wide application of these nanocelluloses. To reduce the production cost of CNFs, some pretreatments have been proposed. In addition, a waste-free technology of nanocrystalline cellulose can be used, which allows completely utilizing materials and chemicals to produce cheap nanocrystalline aggregates (NCA) with zero emission of liquid and solid waste. Due to the low expenses, such a nanostructured product, NCA, will be quite competitive with commercial microcrystalline and powdered celluloses, and therefore it can be served as filler and thickener. Various potential applications of nanocelluloses were also described. [ABSTRACT FROM AUTHOR]

The accumulation of petroleum polymers compromises biodiversity and causes environmental problems. Nanocellulose enhances biodegradability and can improve the physical-mechanical performance of materials. The objective was to produce and characterize hybrid films composed of bacterial cellulose (BC) and plant nanocellulose from Eucalyptus (Euc) or Pinus (Pin). Films were produced by the casting method using filmogenic suspensions with different cellulose nanofibrils (CNFs) proportions from both the sources (0, 25, 50, 75 and 100 %). CNFs suspensions were characterized by transmission electron microscopy. The morphology of the films was analyzed using scanning electron microscopy. In addition, the transparency, contact angle, wettability, oil and water vapor barrier and mechanical properties were also evaluated. The contact angles were smaller for films with BC and the wettability was greater when comparing BC with plant CNFs (0.10 ° s − 1 {\text{s}^{-1}} for 75 % Euc/25 % BC and 0.20 ° s − 1 {\text{s}^{-1}} for 25 % Euc/75 % BC). The water vapor permeability (WVP) of the 100 % BC films and the 25 % Euc/75 % BC composition were the highest among the studied compositions. Tensile strength, Young's modulus and puncture strength decreased considerably with the addition of BC in the films. More studies regarding pre-treatments to purify BC are needed to improve the mechanical properties of the films. [ABSTRACT FROM AUTHOR]

Driven by the demand for various cationic biopolymers in recent years, the quaternization of cellulose nanofibers was carefully investigated to have tight control over their final characteristics. The addition of sodium hydroxide (NaOH) to the reaction mixture is crucial as it catalyzes the conversion of alcohol groups of cellulose into more reactive alcoholate groups. On the other hand, excessive concentration proves to inhibit the reactivity of hydroxyl groups. The addition of glycidyltrimethylammonium chloride (GTMAC) increases the yield of the trimethylammonium chloride content (TMAC) reaction, while in excess it affects the rheological properties of the quaternizated cellulose nanofibers. The effects of NaOH and GTMAC on the TMAC content and rheological properties have been investigated in detail and mathematically evaluated. Furthermore, a comparison of the viscoelastic behavior and shear thinning character of commercial cationic micro- and nanofibrillated cellulose is presented. The research allows to extend the possibility of using cellulose in many applications of cationic biopolymers. [ABSTRACT FROM AUTHOR]

Extracellular matrix (ECM) is essential for tissue development, providing structural support and a microenvironment that is necessary for cells. As tissue engineering advances, there is a growing demand for ECM mimics. Polycaprolactone (PCL) is a commonly used synthetic polymer for ECM mimic materials. However, its biologically inactive surface limits its direct application in tissue engineering. Our study aimed to improve the biocompatibility of PCL by incorporating hemoglobin nanofibrils (HbFs) into PCL using an electrospinning technique. HbFs were formed from bovine hemoglobin (Hb) extracted from industrial byproducts and designed to offer PCL an improved cell adhesion property. The fabricated HbFs@PCL electrospun scaffold exhibits improved fibroblast adherence, proliferation, and deeper fibroblast infiltration into the scaffold compared with the pure PCL scaffold, indicating its potential to be an ECM mimic. This study represents the pioneering utilization of Hb-sourced nanofibrils in the electrospun PCL scaffolds for tissue engineering applications.