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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.

The development of new drug delivery systems for cancer therapy is critical in order to further increase efficacy and reduce peripheral toxicity of current antitumor agents, and so far various targeting strategies have been investigated in this regard. Here we report on the synthesis and characterization of a new drug carrier system where folic acid is grafted at the surface of the oxidized cellulose nanofibers using the Diels Alder strategy. The oxidized cellulose nanofibers grafted with folic acid formed a colloidal system that was loaded with doxorubicin as a model antitumor agent. The system was tested in-vitro using both tumor and normal human cells, and results indicated an increased ability to kill human cells when compared to free doxorubicin. No significant effect of the CNF-bound folic acid causing an increased specificity towards tumor cells versus human fibroblast cells was observed, possibly as a result of a reduced binding potential of folic acid after conjugation to CNF. However, the system demonstrated an increased cellular uptake of doxorubicin by human cells, suggesting the potential to improve the therapeutic efficacy of pharmaceutical actives.

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., 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 Elsevier B.V. All rights reserved.)

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 m 2 /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., 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 Elsevier B.V. All rights reserved.)

This paper presents data related to the research article “Self healing hydrogels composed of amyloid nano fibrils for cell culture and stem cell differentiation” [1]. Here we probed the collective influence of all-trans retinoic acid (RA) and substrate properties (amyloid hydrogel) on human mesenchymal stem cell (hMSC) differentiation. Stem cells were cultured on soft amyloid hydrogels [1,2] in the presence and absence of matrix encapsulated RA. The cell morphology was imaged and assessed via quantification of circularity. Further immunostaining and quantitative real time PCR was used to quantify various markers of differentiation in the neuronal lineage.

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., 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 © 2023 Elsevier Inc. All rights reserved.)

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. STATEMENT OF SIGNIFICANCE: 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., Competing Interests: Declaration of Competing Interests 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 © 2023 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

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., 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 © 2021 Elsevier Inc. All rights reserved.)

Nanocelluloses (NCs), more specifically cellulose nanocrystals and nanofibrils, are a green alternative for the stabilization of fluid interfaces. The adsorption of NCs at oil-water interfaces facilitates the formation of stable and biocompatible Pickering emulsions. In contrast, unmodified NCs are not able to stabilize foams. As a consequence, NCs are often hydrophobized by covalent modifications or adsorption of surfactants, allowing also the stabilization of foams or functional inverse, double, and stimuli-responsive emulsions. Although the interfacial stabilization by NCs is readily exploited, the driving force of adsorption and stabilization mechanisms remained long unclear. Here, we summarize the recent advances in the understanding of NC adsorption regarding kinetics, isotherms, and energetic aspects, as well as their interfacial structure, surface coverage, and contact angle. We thereby distinguish unmodified NCs, covalently modified NCs, and surfactant enhanced adsorption., (Copyright © 2019. Published by Elsevier B.V.)

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)., (Copyright © 2019 Elsevier B.V. All rights reserved.)

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., (Copyright © 2018 Elsevier B.V. All rights reserved.)

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., (Copyright © 2018 Elsevier B.V. All rights reserved.)

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, SNF and CoNFs, and discuss emerging applications for these biopolymer nanofibrils.

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 6wt% 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., (Copyright © 2018. Published by Elsevier B.V.)

Huntington's disease (HD) is recognized as a currently incurable, inherited neurodegenerative disorder caused by the accumulation of misfolded polyglutamine (polyQ) peptide aggregates in neuronal cells. Yet, the mechanism by which newly formed polyQ chains interact and assemble into toxic oligomeric structures remains a critical, unresolved issue. In order to shed further light on the matter, our group elected to investigate the folding of polyQ peptides - examining glutamine repeat lengths ranging from 3 to 44 residues. To characterize these aggregates we employed a diverse array of technologies, including: nuclear magnetic resonance; circular dichroism; Fourier transform infrared spectroscopy; fluorescence resonance energy transfer (FRET), and atomic force microscopy. The data we obtained suggest that an increase in the number of glutamine repeats above 14 residues results in disordered loop structures, with different repeat lengths demonstrating unique folding characteristics. This differential folding manifests in the formation of distinct nano-sized fibrils, and on this basis, we postulate the idea of 14 polyQ repeats representing a critical loop length for neurotoxicity - a property that we hope may prove amenable to future therapeutic intervention. Furthermore, FRET measurements on aged assemblages indicate an increase in the end-to-end distance of the peptide with time, most probably due to the intermixing of individual peptide strands within the nanofibril. Further insight into this apparent time-dependent reorganization of aggregated polyQ peptides may influence future disease modeling of polyQ-related proteinopathies, in addition to directing novel clinical innovations., (Copyright © 2016 Elsevier Ltd. All rights reserved.)