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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]

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]

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]

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]

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]

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]

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]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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]

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]

[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]

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]

Protein misfolding and subsequent generation of amyloid fibrils are associated with a wide range of diseases e. g. Alzheimer's, Huntington's, Parkinson's, type II diabetes, cystic fibrosis, and many others. Aromatic amino acid residues of polypeptide/protein are supposed to play a critical role in formation and stabilization of amyloid fibrils. Herein, we report a synthetic peptide, ALYLV (peptide 1), corresponding to B14‐18 of insulin, that forms nanofibrillar aggregates upon self‐association in aqueous medium. Staining with congo red (CR) and thioflavin t (ThT) establish that these organized nano‐assemblies are amyloidogenic in nature. Interestingly, the structural modification of peptide 1 replacing the centrally located tyrosine residue with valine, ALVLV (peptide 2), significantly reduces the assembly propensity as well as the amyloidogenicity of peptide 2 compared to peptide 1. MTT (3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide) cell survival assay reveals the cytotoxicity of the aggregated peptides on HeLa cells upon 48 h of exposure. Overall, the study explores the aggregation potential, amyloidogenicity, and cytotoxicity of a hotspot of insulin and pinpoints the role of aromatic amino acid residue in amyloidosis. This outcome also illuminates the peptide nano‐assemblies for various biotechnological applications. [ABSTRACT FROM AUTHOR]

• FRV 3 FR was found to self-assemble into nanofibrils and macroscopic hydrogels. • FRV 3 FR adopts a β-turn secondary structure with evidence of aromatic stacking. • The alanine-based peptide FRA 3 FR failed to self-assemble into nanofibrils. • Valine is preferred over alanine in the self-assembly process for these peptides. Small peptides are commonly used monomers for the self-assembly of biologically relevant supramolecular nanomaterials. In this study, the heptameric sequence FRV 3 FR was found to self-assemble into nanofibrils in solution, as confirmed by transmission electron microscopy (TEM), leading to the subsequent formation of hydrogels. Circular dichroism (CD) analysis showed that the FRV 3 FR peptide adopts a secondary structure that closely resembles a β-turn type conformation. An alanine-based peptide termed FRA 3 FR was also studied to highlight the impact of the middle amino acid triad has in self-assembly. Even though the FRA 3 FR showed a similar CD signal, it failed to provide any significant nanostructure or hydrogel formation, demonstrating the ability valine residues over alanine in promoting self-assembly. This work presents preliminary studies on a novel peptide sequence, laying the groundwork for its potential development into a functional peptide-based nanomaterial. [ABSTRACT FROM AUTHOR]

Bovine serum albumin nanofibrils (BSNs) were fabricated under thermal treatment (85 °C) at acidic condition (pH 2.0) and the incubation time on the structural, and physicochemical characteristics were probed. The formation and development of BSNs have been detected and confirmed by Thioflavin T (ThT) fluorescence and circular dichroism (CD) measurements. The structural alterations of bovine serum albumin (BSA) have also been investigated using intrinsic fluorescence and Congo red (CGR) UV–vis spectroscopy. Atomic force microscopy (AFM) outcomes displayed the morphologies of BSNs at varied time, with a diameter of about 3 nm and a contour length of about 200 nm at 24 h. The apparent viscosities of BSNs at three different pH were in the following order: pH 3.0 > pH 5.0 > pH 7.0. Emulsifying and foaming properties of BSA were pronouncedly enhanced through fibrillation, which was highly correlated with the interfacial properties and structural characteristics. Highest EAI 54.2 m2/g was attained at 48 h and no pronounced alterations were observed for EAI at 24 h and 48 h. Maximum value of FC was obtained at 48 h for BSA. This study will provide some useful information in understanding the formation of BSNs and broaden their application in food systems as functional food ingredients. • Bovine serum albumin nanofibrils (BSNs) were formed under heating at acidic condition. • The structural characteristics of bovine serum albumin (BSA) were changed during fibrillation. • The emulsifying and foaming properties of BSA were enhanced during fibrillation. • BSNs exhibited great potential as functional ingredients. [ABSTRACT FROM AUTHOR]

Silk fibroin (SF) from the cocoon of silkworm has exceptional mechanical properties and biocompatibility and is used as a biomaterial in a variety of fields. Sustainable, affordable, and scalable manufacturing of SF would enable its large-scale use. We report for the first time the high-level secretory production of recombinant SF peptides in engineered Pichia pastoris cell factories and the processing thereof to nanomaterials. Two SF peptides (BmSPR3 and BmSPR4) were synthesized and secreted by P. pastoris using signal peptides and appropriate spacing between hydrophilic sequences. By strain engineering to reduce protein degradation, increase glycyl-tRNA supply, and improve protein secretion, we created the optimized P. pastoris chassis PPGSP-8 to produce BmSPR3 and BmSPR4. The SF fed-batch fermentation titers of the resulting two P. pastoris cell factories were 11.39 and 9.48 g/L, respectively. Protein self-assembly was inhibited by adding Tween 80 to the medium. Recombinant SF peptides were processed to nanoparticles (NPs) and nanofibrils. The physicochemical properties of nanoparticles R3NPs and R4NPs from the recombinant SFs synthesized in P. pastoris cell factories were similar or superior to those of RSFNPs (Regenerated Silk Fibroin NanoParticles) originating from commercially available SF. Our work will facilitate the production by microbial fermentation of functional SF for use as a biomaterial. • Pichia pastoris was engineered for high-level silk protein production and secretion. • More than 10 g/L silk fibroin protein can be produced by engineered cell factory. • Self-aggregation of silk fibroin proteins was inhibited by Tween 80. • Nanomaterials produced by recombinant silk fibroin protein exhibited similar properties as regenerative silk fibroin nanomaterials. • Recombinant silk fibroin nanoparticles have excellent drug delivery efficiency. [ABSTRACT FROM AUTHOR]

The functional performance of plant proteins can be enhanced by converting them into nanofibrils using controlled acid-heat treatments. Initially, the impact of heating time on the morphology and properties of nanofibrils prepared from pea proteins was assessed. The pea protein nanofibrils (PPF) were formed by heating at 85 °C and pH 2.0 for different times (0–24 h). Multiple analytical methods were then used to characterize the properties of the nanofibrils, including transmission electron microscopy (TEM), gel electrophoresis (SDS-PAGE), thioflavin T (ThT) fluorescence spectroscopy, molecular flexibility, and surface hydrophobicity. With increasing heating time, the protein molecules were gradually decomposed into small molecular weight peptides, which then assembled into nanofibrils. Initially, the length of the PPFs increased with heating time, but then it decreased, which was attributed to fibril fragmentation. In the food processing industry, pH and temperature are important factors affecting food preparation. For this reason, the effects of pH (2–9) and temperature (55, 85, 100 °C) on the properties of the nanofibrils were explored. These environmental conditions had a strong influence on the morphology and properties of PPFs. For instance, their flexibility increased with increasing pH, whereas their surface hydrophobicity decreased with increasing pH and temperature. Moreover, their charge went from positive to negative as the pH was ascended from below to above their isoelectric point. The findings of the structural properties of protein nanofibrils could provide some new insights into the wider application of nanofibrils in the food industry. [Display omitted] • Pea protein nanofibrils were successfully fabricated. • The formation mechanism of pea protein nanofibrils was investigated. • Heating time has a great influence on the amount and length of fibrils generation. • Hydrophobic and electrostatic interactions were essential in the formation of fibrils. • The effects of pH and temperature on fibrils were clarified. [ABSTRACT FROM AUTHOR]

In this study, a new fibrillation method, i.e., a multiround induction pathway, was proposed to modify the highly rigid structure of conventional whey protein nanofibrils and enhance the stability of Pickering emulsions. In contrast to the conventional self-assembly pathway, in which nanofibrils are formed by aggregation of polypeptides or monomers, the multiround induction pathway involves the use of multiple rounds of homologous seeds to induce whey protein nanofibril formation. The structure of nanofibrils formed by multiround induction was considerably different from that of conventionally self-assembled nanofibrils, with a greater or equal number of nanofibrils formed. Over 6 rounds of induction, the intersheet distance within the cross-β-sheet motifs of the nanofibrils increased (from 10.01 Å to 10.70 Å), and the intersheet stacking structure gradually became looser, consequently displaying a thicker morphology with greater height and periodicity. Compared to conventionally self-assembled nanofibrils, nanofibrils with this characteristic structure exhibited 4.04 times higher interfacial adsorption, an 83.24% lower flocculation index, and 61.29% higher emulsion stability. Differences in the emulsification properties of nanofibrils were attributed to multiround induction, which changed the nanofibril structure compared to conventional self-assembly. Some hydrophobic peptides at the β-sheet and α-helix positions were not involved in the construction of cross-β-sheet motifs, which made the nanofibrils more flexible and hydrophobic. These findings suggested that nanofibrils prepared via the multiround induction pathway had unique properties that might be significant for the fabrication of food-grade Pickering emulsions with excellent stability. [Display omitted] • A new pathway, multiround induction (MI), modifies the nanofibril structure. • Highly flexible, loose, and hydrophobic nanofibrils can be fabricated by MI. • Some hydrophobic peptides in building blocks of cross-β-sheets are released during MI. • Modified nanofibrils formed by MI can enhance the stability of Pickering emulsions. [ABSTRACT FROM AUTHOR]

One major goal in tissue engineering is to create functional materials, mimicking scaffolds in native tissues, to modulate cell function for tissue repair. Collagen is the most abundant structural protein in human body. Though collagen I (COLI) and collagen III (COLIII) are the predominant collagen types in connective tissues and they form stable hybrid fibrils at varied ratios, cell responses to the hybrid matrices are underinvestigated. In this work, we aim to explicate the distinctive roles of COLI and COLIII in fibroblast activation. Unidirectionally aligned COLI, COLIII and COLI-COLIII hybrid nanofibrils were generated via epitaxial growth of collagen on mica. AFM analyses revealed that, with the increase of COLI/COLIII ratio, the fibril width and stiffness increased and the binding affinity of cells to the matrix decreased. A hybrid matrix was found to activate fibroblasts the most effectively, characterized by extensive cell polarization with rigid stress fiber bundles and high α-SMA expression, and by the highest-level of collagen synthesis. It is ascribed to the fine balance between biochemical and biophysical cues achieved on the hybrid matrix. Thus, matrices of aligned COLI-COLIII hybrid fibrils and their derived multifunctional composites can be good candidates of implantation scaffolds for tissue regeneration. • Collagen I and collagen III have distinctive roles in fibroblast activation. • Unidirectionally aligned collagen nano-fibrils prompted cell polarization. • The stiffer COLI fibrils exert a higher force to cells. • α1β1-integrin binds stronger to COLIII than to COLI. • COLI-COLIII hybrid fibrils promoted collagen synthesis the most effectively. [ABSTRACT FROM AUTHOR]

In this work we studied the influence on the mechanical and physical properties of paper made from short-fiber pulp by adding different percentages of nanofibrillated cellulose. Bleached Eucalyptus sp. Kraft pulp was submitted to three different grinding regimes to obtain the nanofibrillated cellulose of 2, 10 and 20 passes through the grinder. Paper was produced by incorporating nanofibrillated cellulose in the proportions of 3, 6 and 9 wt%. The results showed that the addition of nanofibrillated cellulose increased the following mechanical properties: tensile index, tear index, and burst index. The porosity and the apparent density decreased. The addition of 9% of nanofibrillated cellulose obtained from 2 grinding passes provided the best results with improvements in tensile, burst and tear resistance of 111, 114 and 70%, respectively, in comparison to normal paper. The improvement in the mechanical properties of paper is related to the very dense network of hydrogen bonds, resulting in greater surface area obtained after defibrillation. Nanofibrillated cellulose can be applied to improve paper quality and for reinforcing composites. [ABSTRACT FROM AUTHOR]

In the current research, whey protein isolate (WPI) solution was nanofibrillated or denatured by heating at pH 2.0 or 8.0, respectively. The formation of whey protein nanofibrils with a nanometric thickness and micrometric length was confirmed by atomic force microscopy. Subsequently, different concentrations of citric acid (0–200 mM) as a gelling agent was used to fabricate cold-set hydrogels from heat-denatured, fibrillated, and mixed fibrillated/heat-denatured protein solutions at pH value of 8.0. The fibrillated and mixed fibrillated/heat-denatured solutions required lower concentrations of citric acid to form self-supporting gels compared to the heat-denatured WPI. The formation of covalent bonds between the network-building protein units through the citric acid-induced gelation was confirmed by gel electrophoresis and Fourier transform infrared spectroscopy. Hydrogels made of nanofibrillated and mixed solutions were firmer, had a lower water holding capacity, and showed more degradation at the simulated gastric fluid than the gel from heat-denatured WPI. The increase in citric acid concentration also increased the firmness and gastric degradation stability of the hydrogel samples. The results also showed that the hydrogels in the presence of nanofibrils were degraded much more than the fibril-free gel samples in the simulated gastric condition. Generally, these findings suggested that the combination of nanofibrillation and citric acid-mediated cross-linking could be employed to fabricate hydrogels with excellent techno-functional attributes. [ABSTRACT FROM AUTHOR]

Bio-based additives are currently of special interest in the construction industry. The use of biopolymers increases every year owing to the industry's goal to provide non-toxic and emission-free construction products. Therefore, the addition of bio-based nanofibers to cement paste was studied. The bio-based nanofibers were isolated from fique fibers as cellulose nanofibrils (CNF) through mechanical and chemical treatments. The CNF acted as viscosity-modifying agent for the cement paste, thereby increasing its yield point exponentially with small additions. Moreover, the CNF increased the hydration degree and storage modulus of the cement paste, which were measured through a dynamic thermo-mechanical analysis (DMA) at high temperatures. Furthermore, the CNF-modified cement paste presented less microcracking under stress and at high temperatures. Thus, a synergetic interaction occurred between the cement paste and the bio-based nanofibers isolated from fique fibers. • A new bio-based cement additive is studied. • Cellulose nanofibrils extracted from fique fibers enhance cement-based materials. • Cellulose nanofibrils increased the cement paste plastic yield point, stiffness and microcracking resistance. [ABSTRACT FROM AUTHOR]

Chitin whiskers are promising reinforcing filler for composites due to their mechanical properties, renewable nature and low cost. A new method for preparation of β-chitin fibrils from squid pens in ascorbic acid aqueous solutions (AscA) was developed. Stirring of the solution with 2 g/l AscA for 2 h disperses the swollen chitin to individualized fibrils with an aspect ratio > 250. The optimal conditions of β-chitin exfoliation in acrylic acid (AcrA) aqueous solution were found (0.75–2 g/l, 3–4 h). TEMPO-oxidized β-chitin fibrils were chosen as a reference sample for comparison of different methods. 0.1% chitin suspensions exfoliated in AscA and AcrA solutions show similar gel-like behavior with a storage modulus (G ′) of 98 ± 23 and 34 ± 12 Pa, respectively, whereas G ′ of 0.1% dispersion of the TEMPO-oxidized β-chitin fibrils was 0.015 ± 0.005 Pa only. Composites based on poly(acrylic acid) comprising 1–3 wt% of β-chitin fibrils were fabricated by polymerization filling. Mechanical properties of the composites were investigated in dry state in the temperature range of 25–250 °C and at controlled relative humidity in the range from 53.6% to 100%. It was revealed that the maximum reinforcing effect is achieved at high temperature (>120 °C) and high relative humidity (≥75.3%RH). [ABSTRACT FROM AUTHOR]

Highlights • Modified cellulose nanofibrils with high quaternary amines were achieved. • As(V) removal was rapid and the pseudo second order model best fitted the data. • The adsorption isotherms of As(V) removal were better described by the Langmuir model. • The Langmuir maximum capacity of modified cellulose nanofibrils was 25.5 mg g−1. • As(V) adsorption onto modified cellulose nanofibrils is spontaneous and exothermic. Abstract Cellulose nanofibrils (CNF) functionalized by introduction of trimethylammonium chloride were investigated for the uptake of arsenate [As(V)] from aqueous solutions. The modified-CNF was characterized using Energy Dispersive Spectrometry (EDS), argentometric titration, Boehr titration, zeta-potential, Scanning Electron Microscopy (SEM), Fourrier Transform Infrared (FTIR) spectroscopy, Nuclear Magnetic Resonance (NMR) spectroscopy, Brunauer-Emmet-Teller (BET), and Dynamic Light Scattering (DLS). The modified-CNF was effective for As(V) removal from laboratory and field samples. The As(V) adsorption was rapid and equilibrium was attained within two hours. The kinetic data were adequately described by the pseudo-second-order kinetics model suggesting that As(V) adsorption onto modified-CNF involves electrostatic forces and bonds between As(V) and adsorption sites. The adsorption isotherm data were well correlated with model. The modified-CNF exhibited an As(V) adsorption capacity (q e) of approximately 25.5 mg g−1. Competitive adsorption between As(V) and anions including NO 2 −, NO 3 −, and SO 4 2− was investigated and the results showed negligible influence on As(V) removal. However, PO 4 3− presence slightly reduced As(V) adsorption. Thermodynamics study showed that the As(V) adsorption onto modified-CNF is temperature dependent and is spontaneous and exothermic. Overall, the results of this study demonstrated that modified-CNF offers a propitious alterative for As(V) removal from water. [ABSTRACT FROM AUTHOR]

The self-assembly behavior of 1,3:2,4-dibenzylidene-D-sorbitol (DBS) in ternary solvents has been systematically investigated for the use of kerosene gel in the aerospace propulsion. DBS forms a yield viscoelastic gels in a wide range of kerosene/hexanol/DMSO solvent concentrations despite the fact that DBS is incapable of gelling kerosene fuel. The gelation behavior of DBS in the solvent mixture is predicted using the Hansen solubility parameters. The polar parameter (δP) and hydrogen bonding (δH) parameter lie in the range of 1.96 ≤ δP ≤ 4.30 J0.5cm−1.5 and 3.40 ≤ δH ≤ 7.30 J0.5cm−1.5 respectively for the formation of gel in kerosene/hexanol/DMSO system. The phase transition temperature (Tf) of DBS gel is determined using temperature sweep measurement and predicted using modified Friedrich (MF) relation which is found be in close agreement with an average deviation of ± 10 °C. However, the deviation becomes larger when δP > 4.30 and δH > 7.30, in other words, with increase in the solvent polarity. As the solvent polarity or concentration of hexanol increases in the mixture, the gels exhibit a low Tf and G max ′ value because of the hindrance of self-assembling ability of DBS due to the intermolecular hydrogen bonding between DBS and solvents. The viscoelastic behavior of DBS gels is investigated using the oscillation sweep measurements and the storage modulus G′ is found to be higher than the loss modulus G″ for larger stress amplitude and frequency, indicating a solid-like nature of the gels. Furthermore, the microstructure analysis shows the presence of 3D nano-fibrillar morphology, which further depends on the solvent polarity. Microstructure changes from 'rope-like' fiber aggregate (Hex100; CH = 88 wt%) to a 'web-like' structures (Hex25; CH = 25 wt%), when the CH is decreased in the solvent mixture. [ABSTRACT FROM AUTHOR]

Highlights • Evaluation of LPMO activity on cellulosic substrates of different crystallinity. • SamLPMO10C is more active on celluloses with high crystallinity and accessibility. • Synergism of LPMOs and endoglucanases on NFC production from flax. • First study reporting the effect of a bacterial LPMO in nanocellulose production. Abstract A series of cellulosic substrates has been produced, treated with lytic polysaccharide monooxygenase (LPMO) from Streptomyces ambofaciens (SamLPMO10C), and analyzed by high performance anion exchange chromatography (HPAEC) with pulsed amperometric detection (PAD). The activity of the bacterial LPMO showed high variability depending on the origin and degree of crystallinity of the substrate. Additionally, we tested the effectiveness of SamLPMO10C in the nanofibrillation of flax, a high crystalline agricultural fiber, as a single pretreatment or in combination with cellulases. All pretreatments were followed by a mechanical defibrillation by high-pressure homogenization (HPH) to obtain cellulose nanofibrils (NFC). The combined LPMO-cellulase treatment showed higher fibrillation yield, optical transmittance and carboxylate content than control reactions. Therefore, it could be explored as a promising green alternative to reduce the energy consumption in the production of NFC. To our knowledge, this is the first study reporting the effect of a bacterial LPMO in nanocellulose production. [ABSTRACT FROM AUTHOR]

Toned milk is a lower-fat, healthier alternative to whole milk that still contains all essential nutrients. A number of methods have been developed to improve the functionality of toned milk and make it more appealing to the consumers. However, these methods often involve extensive processing techniques and can be expensive. Therefore, alternative methods are needed. Proteins are well known for their ability to form well-defined nanofibril materials that can be used as a scaffold for various applications. In this article, a straightforward self-assembly process was used to load inulin into protein nanofibrils, creating unique composite nanofibrils. Characterization using AFM and SEM revealed well-defined composite nanofibrils with an average diameter of 4–6 nm and lengths ranging from 0.25 μm up to 10 μm. FT-IR and in-vitro release assays show that inulin was successfully attached to prepared protein nanofibrils. The composite nanofibrils were tested on toned milk to enhance the physico/chemical properties and nutritional values. The findings can be applied to the food industry to create a number of novel functional food products cost-effectively. • Conventional methods for improving toned milk's quality often involve complex processes. • This study introduces innovative methods to enhance its functionality in a simpler, more cost-effective manner. • Nanofibrils were prepared and used as scaffold to attach the active ingredients. • Inulin successfully loaded onto nanofibrils enhances tonned milk functionality and nutrient values. • Similar bio-active ingredients create novel functional foods for widespread use in the food industry. [ABSTRACT FROM AUTHOR]

Enzymatic hydrolysis is an effective method to improve the physicochemical properties of soy protein isolate (SPI) nanofibrils and expand their application in stabilizing Pickering emulsion. In this work, the effects of enzymatic hydrolysis on the SPI fibrillation and the stabilization mechanisms of SPI hydrolysate nanofibrils for Pickering emulsion were investigated. According to sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) images and Thioflavin T (ThT) fluorescence data, a higher degree of hydrolysis (DH) contributed to releasing more small molecular weight peptides (mainly from α, α′, and β subunits) to improve apparent rate constant and surface hydrophobicity during fibrillation. When DH increased to 8%, SPI hydrolysate could form long and flexible nanofibrils and possessed the highest content of β-sheet (21.40%), when heated for 12 h. Enzymatic hydrolysis played various positive impacts on the interfacial properties of nanofibrils, including faster interfacial adsorption and near-neutral wettability (92.87°). SPI hydrolysate nanofibrils could impart enhanced gel-like structure and exceptional thermal stability to Pickering emulsions, resulting in a decrease in droplet size from 52.06 μm to 32.74 μm. This work will enhance the exploration of the formation mechanism of nanofibrils and broaden their application in the functional emulsion. • Enzymatic hydrolysis released peptides and accelerated the formation rate of nanofibrils. • SPI hydrolysate could form longer and more flexible nanofibrils with higher H 0. • SPI hydrolysate nanofibril endowed Pickering emulsion with outstanding stability. • Enzymatic hydrolysis improved interfacial adsorption and wettability of nanofibril. • Pickering emulsion of SPI hydrolysate nanofibril had enhanced gel-like structure. [ABSTRACT FROM AUTHOR]

Graphical abstract The SEM-images of the transition zones of samples: (a) – 50% PTFE + 50% Al, (b) – 30% PTFE + 70% Cu 30%, (c) – 30% PTFE + 70% Ni. Highlights • The composites produced with the use of the explosive pressing of the mixtures of metals with polytetrafluorethylene. • Morphology, molecular structure, phase composition and a number of properties of the composites were study. • The explosive pressing results in the partial destruction of polytetrafluorethylene, oxidation and fluorination of metals. • The formation of the intermediate layers consisting of nanofibrils enhances the adhesion of metal to polymer promoting. Abstract This paper presents the results of studying the composites produced with the use of the explosive pressing of the mixtures of metals with polytetrafluorethylene. The used metals are aluminium, copper and nickel. Particular emphasis has been placed on the revealing of morphology, molecular structure, phase composition and a number of properties of the composites under study. The explosive pressing, on retention of the characteristics of the mixture components in whole, results in the partial destruction of polytetrafluorethylene, insignificant oxidation and fluorination of metal and formation of the intermediate layer consisting of nanofibrils which enhances the adhesion of metal to polymer promoting thereby formation of durable composite. [ABSTRACT FROM AUTHOR]

Abstract This work addresses the fabrication and characterization of gels from emulsions stabilized by heat-denatured and nanofibrillated whey protein isolate (WPI) using citric acid and CaCl 2 as cold-gelling agents. Nano-thick fibrils and wormlike aggregates were produced by heating of WPI at pH 2.0 and 8.0, respectively. Fibrillated WPI, heat-denatured WPI, and their mixture at a concentration of 65 mg mL−1 and pH 8.0 were used to stabilize oil-in-water emulsions. Emulsions stabilized by fibrillated WPI showed a higher creaming stability than samples stabilized by heat-denatured and mixed fibrillated/heat-denatured WPI. However, they were more polydisperse and had larger droplets. Gelation of emulsions by citric acid through the generation of covalent bonds was confirmed by OPA colorimetric method and FT-IR spectroscopy. Emulsion gels prepared by citric acid-mediated cross-linking were firmer than those formed by CaCl 2 and also showed a higher ability to hold water and retain oil. Scanning electron microscopy also demonstrated a more open and porous structure for ion-induced emulsion gels compared to citric acid-induced counterparts. Generally, the results indicated that the citric acid as a new gelling agent and different forms of WPI aggregates can be used in the formulation of edible emulsion gels with modifiable functional properties. [ABSTRACT FROM AUTHOR]

Bioinspiration from hierarchical structures found in natural environments has heralded a new age of advanced functional materials. Nanocellulose has received significant attention due to the demand for high-performance materials with tailored mechanical, physical and biological properties. In this study, nanocellulose fibrils, nanocrystals and a novel mixture of fibrils and nanocrystals (blend) were prepared from softwood biomass using the AVAP® biorefinery technology. These materials were characterized using transmission and scanning electron microscopy, and atomic force microscopy. This analysis revealed a nano- and microarchitecture with extensive porosity. Notable differences included the nanocrystals exhibiting a compact packing of nanorods with reduced porosity. The NC blend exhibited porous fibrillar networks with interconnecting compact nanorods. Fourier transform infrared spectroscopy and X-ray diffraction confirmed a pure cellulose I structure. Thermal studies highlighted the excellent stability of all three NC materials with the nanocrystals having the highest decomposition temperature. Surface charge analysis revealed stable colloid suspensions. Rheological studies highlighted a dominance of elasticity in all variants, with the NC blend being more rigid than the NC fibrils and nanocrystals, indicating a double network hydrogel structure. Given these properties, it is thought that these materials show great potential in (bio)nanomaterial applications where careful control of microarchitecture, surface topography and porosity are required. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Biopolymer nanofibrils exhibit exceptional mechanical properties with a unique combination of strength and toughness, while also presenting biological functions that interact with the surrounding environment. These features of biopolymer nanofibrils profit from their hierarchical structures that spun angstrom to hundreds of nanometer scales. To maintain these unique structural features and to directly utilize these natural supramolecular assemblies, a variety of new methods have been developed to produce biopolymer nanofibrils. In particular, cellulose nanofibrils (CNFs), chitin nanofibrils (ChNFs), silk nanofibrils (SNFs) and collagen nanofibrils (CoNFs), as the four most abundant biopolymer nanofibrils on earth, have been the focus of research in recent years due to their renewable features, wide availability, low-cost, biocompatibility, and biodegradability. A series of top-down and bottom-up strategies have been accessed to exfoliate and regenerate these nanofibrils for versatile advanced applications. In this review, we first summarize the structures of biopolymer nanofibrils in nature and outline their related computational models with the aim of disclosing fundamental structure-property relationships in biological materials. Then, we discuss the underlying methods used for the preparation of CNFs, ChNFs, SNFs and CoNFs, and discuss emerging applications for these biopolymer nanofibrils. [ABSTRACT FROM AUTHOR]

Ammonium persulfate has been known as an agent for obtaining nanocellulose in recent years, however most research has focused on producing cellulose nanocrystals. A lack of research about combined ammonium persulfate oxidation and common mechanical treatment in order to obtain cellulose nanofibrils has been identified. The objective of this research was to obtain and investigate carboxylated cellulose nanofibrils produced by ammonium persulfate oxidation combined with ultrasonic and mechanical treatment. Light microscopy, atomic force microscopy (AFM), powder X-Ray diffraction (PXRD), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and Zeta potential measurements were applied during this research. The carboxylated cellulose suspension of different fractions including nanofibrils, microfibrils and bundles were produced from bleached birch Kraft pulp fibers using chemical pretreatment with ammonium persulfate solution and further defibrillation using consequent mechanical treatment in a high shear laboratory mixer and ultrasonication. The characteristics of the obtained nanofibrils were: diameter 20-300 nm, crystallinity index 74.3%, Zeta potential -26.9 ± 1.8 mV, clear FTIR peak at 1740 cm-1 indicating the C=O stretching vibrations, and lower thermostability in comparison to the Kraft pulp was observed. The proposed method can be used to produce cellulose nanofibrils with defined crystallinity. [ABSTRACT FROM AUTHOR]

Abstract: The experimental study of polymer growth on spatially unconstrained flat silica surfaces is presented for propylene and ethylene polymerization in liquid and gas phases with high activity metallocene catalyst (rac‐Et(Indenyl)2ZrCl2/ methylaluminoxane at 30–70 °C and 30–50 psig. The study shows a surprisingly rich spectrum of nascent morphologies for each polymer synthesized in two different reaction phases. In propylene polymerization in a liquid phase, polypropylene nanofibrils are first formed at the catalyst sites and quickly develop into microglobular morphology, whereas in ethylene polymerization in a liquid phase, polyethylene nanofibrils formed at the catalyst sites grow to a ribbon‐like morphology. In gas phase polymerization where polymerization rate is much lower due to low monomer concentration, both polymers grow to compact aggregates of globules. Unlike in liquid phase polymerization, no ribbon‐like structure is formed in ethylene polymerization. The sequential polymerization of these olefin monomers has also been carried out and the experimental data show two distinct regions of corresponding polymers as observed in separate ethylene and propylene homopolymerization experiments. [ABSTRACT FROM AUTHOR]

Regenerated Silk biomaterials are usually pre-formed from silk fibroin solutions. However, the dissolution of silk fibroin in proper solvents by a simple and low cost way is still a challenge. Here, we employed a CaCl 2 -methanol solvent system with a very low CaCl 2 concentration of 6 wt% to dissolve silk fibroin. During the dissolution process, the evaporation of methanol cause the changing of solvation sheath of ions in the solvent. The remaining solvent with the incomplete solvation sheath is absorbed by the silk fiber and interacts with fibroin chains to complete the solvation sheath, which accounts for the dissolution of silk fibroin. Silk fibroin dissolution stops as all the solvation sheaths are complete. The final CaCl 2 concentration is ca. 26% and silk fibroin is completely dissolved with a yield of about 90%. Silk fibroin is dissolved into multi-scale nanofibrils solution which is potential for producing regenerated silk fibroin materials for functional applications. [ABSTRACT FROM AUTHOR]

Abstract: Marine macrofoulers (e.g., barnacles, tubeworms, mussels) create underwater adhesives capable of attaching themselves to almost any material. The difficulty in removing these organisms frustrates maritime and oceanographic communities, and fascinates biomedical and industrial communities seeking synthetic adhesives that cure and hold steadfast in aqueous environments. Protein analysis can reveal the chemical composition of natural adhesives; however, developing synthetic analogs that mimic their performance remains a challenge due to an incomplete understanding of adhesion processes. Here, it is shown that acorn barnacles (Amphibalanus (=Balanus) amphitrite) secrete a phase‐separating fluid ahead of growth and cement deposition. This mixture consists of a phenolic laden gelatinous phase that presents a phase rich in lipids and reactive oxygen species at the seawater interface. Nearby biofilms rapidly oxidize and lift off the surface as the secretion advances. While phenolic chemistries are ubiquitous to arthropod adhesives and cuticles, the findings demonstrate that A. amphitrite uses these chemistries in a complex surface‐cleaning fluid, at a substantially higher relative abundance than in its adhesive. The discovery of this critical step in underwater adhesion represents a missing link between natural and synthetic adhesives, and provides new directions for the development of environmentally friendly biofouling solutions. [ABSTRACT FROM AUTHOR]

The functional attributes of globular proteins can be extended by controlling the nature of the aggregates they form. In this study, the effect of thermal treatment (85°C/20 min) and high pressure microfluidization (20,000 psi, 1 pass) on the physical properties of whey protein isolate solutions (5–9%; pH 2) was investigated. Heating solutions of native whey protein isolate (8 wt%) under these acidic conditions led to the formation of highly viscous solutions (η = 306 mPa s) with low turbidity (τ = 0.04 cm −1 ), which was attributed to the formation of protein fibrils (effective d = 310 nm). Microfluidization of these protein fibrils decreased their length (effective d = 97 nm) leading to a substantial reduction in solution viscosity (η = 3.8 mPa s), and a slight reduction in turbidity (τ < 0.03 cm −1 ). The impact of solution pH (2–7) on the appearance and rheology of native, heated, and heated-microfluidized whey protein isolate solutions was then examined. For all systems, highly turbid solutions (τ > 1 cm −1 ) were formed at pH values close to the isoelectric point of the whey proteins (pH 4.5) due to protein self-association caused by reduction of the electrostatic repulsion between the protein molecules. Highly viscous or gelled solutions were formed for the heated and heated-microfluidized proteins across a wide pH range, which was attributed to the presence of fibrils. The study showed that the functional attributes of whey proteins can be modulated by thermal and high-pressure homogenization treatment. [ABSTRACT FROM AUTHOR]

Somatostatin-14 is a native neuropeptide with widespread functions in the body. Self-assembly of somatostatin-14 into amyloid-like nanofibrils has been previously demonstrated in aqueous media. We here hypothesize that the somatostatin nanofibrils can form a stable depot that release monomers in a controlled manner. This study aims to investigate if somatostatin monomers are released from physical hydrogels formed in water and in the presence of electrolytes. The release kinetics of the somatostatin monomers is investigated for the first time. This is correlated with the rheological properties of the hydrogels formed. We demonstrate that at the concentrations tested, there is release of somatostatin monomers from the hydrogels following a novel hybrid model of zero-order and first-order release. In the presence of electrolytes, somatostatin hydrogels demonstrated higher elastic moduli (G′) which correlates to the narrower and higher density of nanofibrils observed with TEM. The presence of electrolytes resulted in a slower release of the somatostatin monomers and in a lower cumulative percentage released over 48 hrs. It is questionable that the concentrations released will be therapeutically effective. However, self-assembled somatostatin hydrogels have the potential to act as a depot for ocular drug delivery. [ABSTRACT FROM AUTHOR]

Development of strong cellulose nanofibril (CNF) networks for advanced applications, such as in the biomedical field, is of high importance owing to the biocompatible nature and plant-based origin of cellulose nanofibrils. Nevertheless, lack of mechanical strength and complex synthesis methods hinder the application of these materials in areas where both toughness and manufacturing simplicity are required. In this work, we introduce a facile method for the synthesis of a low solid content (< 2 wt%), covalently crosslinked CNF hydrogel where Poly (N-isopropylacrylamide) (NIPAM) chains are utilized as crosslinks between the nanofibrils. The resulting networks have the capability to fully recover the shape in which they were formed after various drying and rewetting cycles. Characterization of the hydrogel and its constitutive components was performed using X-ray scattering, rheological investigations and uniaxial testing in compression. Influence of covalent crosslinks was compared with networks crosslinked by the addition of CaCl 2. Among other things the results show that the mechanical properties of the hydrogels can be tuned by controlling the ionic strength of the surrounding medium. Finally, a mathematical model was developed based on the experimental results, which describes and predicts to a decent degree the large-deformation, elastoplastic behavior, and fracture of these networks. [Display omitted] [ABSTRACT FROM AUTHOR]

In this study, a novel technology involving radio frequency heating (RF) was applied to promote the production of whey protein isolate (WPI) nanofibrils. As the prolonged treatment time, gradual increases were observed in the conversion rate (>16 h with the conventional processes), fluorescence intensity, and free amino acid content of WPI. During the fibrillation process, WPI was hydrolyzed into small molecular weight peptides that self-assembled into fibrils, resulting in a significant increase in the ζ-potential and surface hydrophobicity. Conformational and structural changes that favored an increased content of β-sheets were confirmed by Fourier transform infrared and circular dichroism spectroscopy. A linear fibril structure with a proper aspect ratio (length/diameter, 35.50 ± 0.39) formed at 7 h. Moreover, the good resistance to proteolytic digestion (especially gastric stage) of certain fibrils makes them suitable for application as nutraceutical delivery vehicles. Our findings move a step forward for WPI fibrillation by RF heating. [Display omitted] • Whey protein isolate (WPI) nanofibril was formed via radio frequency (RF) heating. • RF induced a reduction in fibrillation time and degree of browning in WPI. • RF treatments led to an increase in surface hydrophobicity and β-sheet level. • The longer and more flexible fibrils were observed by 7 h fibrillation process. • Some nanofibrils exhibited resistance to proteolytic digestion in vitro. [ABSTRACT FROM AUTHOR]

Soy protein isolate (SPI) was isolated from Indonesian soybean var. Grobogan and converted into protein nanofibrils. Their functionalities as a food thickener and building blocks for microcapsules were investigated and compared with those of commercial whey protein isolate (WPI). The isolation yield was about 58% with SPI's protein content of about 90% on dry basis. Long, curved, and branched SPI fibrils with a few nanometers of diameter were obtained by heating SPI suspension at pH 2.0. The solution of SPI fibrils was shear thinning with much higher viscosity than the unheated SPI which was Newtonian. The fibrils showed a good potential as building blocks of microcapsules prepared by layer-by-layer adsorption method, which were similar to WPI fibrils. [ABSTRACT FROM AUTHOR]

An oil-in-water (o/w) emulsion is a system where the oil droplets are dispersed within a watery phase. The most important function of emulsions is their ability to incorporate lipophilic components into food matrices. Thus, it is crucial to develop an emulsion that is highly stable. This work was aimed at developing a palm olein o/w emulsion stabilized by a whey protein isolate nanofibrils-alginate complex, as well as evaluating the influence of oil load and the homogenization process (both pressure and cycle) on the characteristics of the o/w emulsions. Emulsions were analyzed for droplet size, zeta potential, viscosity, creaming stability, and morphology. The results showed that an increase in oil load led to a larger droplet size, less negative zeta potential, and emulsions that were more viscous and less stable. On the other hand, increasing homogenization pressure and the number of homogenization cycles resulted in a smaller droplet size, more negative zeta potential, and emulsions that were less viscous and more stable. Emulsions with a smaller droplet size and better stability resulted from lower oil load, high homogenization pressure and more homogenization cycles. [ABSTRACT FROM AUTHOR]

The ability to tune the inter-subunit interaction within the virus capsid may be critical to assembly and biological function. This process was extended here with peptide/DNA co-assembled viral mimics. The resulting co-assemblies, formed and stabilized by both peptide nanofibril–DNA and peptide nanofibril–nanofibril interactions, were tuned through hydrophobic packing interactions of the peptide sequences. By strengthening peptide side-chain complementarity and/or elongating the peptide chain (from 4 to 8 residues), we report strengthening the inter-nanofibril interaction to create stable nanococoons that give high gene-transfection efficacy. [ABSTRACT FROM AUTHOR]