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• The Mannich-based curcumin-modified strategy drew inspiration from plant cell walls. • Curcumin-modified cellulose was produced with large-scale and versatile method. • This modified cellulose showed durable antimicrobial and UV-protective performance. Cellulose is a versatile and renewable material used in clinical settings for dressings, masks, and bedding. However, adding functions like UV-shielding, antiviral, and antibacterial properties can be challenging due to its poor adhesion and reduced effectiveness over time. Inspired by the natural structure of plant cell walls, we propose a scalable and versatile strategy by introducing curcumin and lysine to the cellulose surface via the Mannich reaction to achieve a durable antimicrobial and UV-protective cellulose surface. The ensuring chemical configuration was characterized through Nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. Additionally, X-ray diffraction analysis confirmed that the modification occurred exclusively at the cellulose surface. We found curcumin-modified sulfated nanocellulose nanofibrils (CL-SCNF) entirely block ultraviolet rays at wavelengths of 200–400 nm (UVA, UVB, and UVC) while providing 82.1 % transparency in the visible spectrum. The resultant silver bonding cellulose products exhibit high antiviral, antibacterial, and antifungal performance against bacterial phage-X174, Escherichia coli, Staphylococcus aureus, and Candida albicans. Furthermore, the strong coordination bonding of silver ions with the β -diketone system endows the final textiles with good washing stability, which can maintain 99 % of antimicrobial activity after repeated washing. This eco-friendly and highly scalable method for fabricating antimicrobial cellulose surfaces will be attractive to manufacturers of protective equipment and textiles, as it offers great potential for applications in a wide range of fields. [ABSTRACT FROM AUTHOR]

[Display omitted] • The CPB aerogel was fabricated via the formation of dynamic enamine bonds. • A maximum adsorption capacity toward MO up to 1013.11 mg g-1 was achieved at 25 °C. • The aerogel could be used to selectively remove anionic dyes form ternary mixtures. • The adsorbent exhibited great antibacterial activity. • There were two possible strategies for recycling the absorbed CPB aerogel.ab. Motivated by sustainable development, the huge pressure of harmful dyes wastewater treatment has highlighted an urgent need to develop more effective biomass adsorbents for selective removal and separation of dyes. Herein, cellulose-based aerogel adsorbent (CPB) is successfully prepared through a novel crosslinking strategy for static and dynamic dye removal, starting with the fabrication of cellulose acetoacetate (CAA) and β-cyclodextrin acetoacetate (β-CDAA) through transesterification process, followed by the crosslinking of polymer chains using polyethyleneimine (PEI) through the formation of dynamic enamine bonds and the freeze-drying treatment of three-dimensional (3D) network structures. A maximum adsorption capacity toward methyl orange (MO) up to 1013.11 mg g−1 is achieved at 25 °C. Besides, the CPB aerogel has abundant surface positive charge, which can be employed to selectively remove anions dyes from ternary mixed systems and has additional antibacterial activity. More importantly, the CPB material based on the dynamic crosslinking strategy can be regulated by adjusting pH, which greatly facilitates the reprocessing and utilization of the adsorbent. The cellulose-based aerogel presented in this work could be an extremely promising material for dye wastewater treatment. [ABSTRACT FROM AUTHOR]

Virus cross-infection via surfaces poses a serious threat to public health. Inspired by natural sulfated polysaccharides and antiviral peptides, we prepared multivalent virus blocking nanomaterials by introducing amino acids to sulfated cellulose nanofibrils (SCNFs) via the Mannich reaction. The antiviral activity of the resulting amino acid-modified sulfated nanocellulose was significantly improved. Specifically, 1 h treatment with arginine modified SCNFs at a concentration of 0.1 g/mL led to a complete inactivation of the phage-X174 (reduction by more than three orders of magnitude). Atomic force microscope showed that amino acid-modified sulfated nanofibrils can bind phage-X174 to form linear clusters, thus preventing the virus from infecting the host. When we coated wrapping paper and the inside of a face-mask with our amino acid-modified SCNFs, phage-X174 was completely deactivated on the coated surfaces, demonstrating the potential of our approach for use in the packaging and personal protective equipment industries. This work provides an environmentally friendly and cost-efficient approach to fabricating multivalent nanomaterials for antiviral applications. [Display omitted] • Amino acids were successfully introduced to SCNFs by the Mannich reaction. • Amino acid-modified SCNFs could greatly enhance the antiviral performance. • Bio-inspired virus-blocking nanomaterials were fabricated without toxic solvent. [ABSTRACT FROM AUTHOR]

Cellulose provides promising alternatives to synthetic plastics to achieve a low carbon footprint and biodegradable materials, which have significant positive impacts on environmental protection and on human health. In this work, sulfated holocellulose fibers and sulfated holocellulose nanofibrils (SHCNFs) are prepared using a combination of delignification with derivatization to achieve high fiber yield, superior recycling performance, and less energy consumption of the final products by means of preserving hemicellulose. Derivatization of the surface with sulfate groups provides a further means to avoid excessive aggregation between adjacent cellulose surfaces. Interestingly, hemicellulose increases the accessibility of holocellulose fibers and reduces the embodied energy during sulfate esterification. The presence of hemicellulose imparts high optical transmittance, mechanical performance (ultimate strength, 390 MPa; Young's modulus, 33 GPa), and recyclability for SHCNFs. This combination of two treatments can unlock the greater potential of cellulose as a sustainable material over its entire life cycle. [Display omitted] [ABSTRACT FROM AUTHOR]

Nowadays, about 30% of food is damaged or wasted during the transport and preservation process. Therefore, there exists a big challenge to enhance the shelf-life and safety of perishable vegetables and fruits at a minimal cost. Herein, a highly scalable and innovative natural-derived bio-nanocomposites based on the available and low-cost materials (wood powder and wheat gluten) is designed for food preservation. Both the lignocellulose nanofibers (LCNF)-wheat gluten (WG) hybrid coatings on the surface of fruits and the hybrid packaging films show prominent preservation performance for six kinds of fruits with different respiratory metabolisms to prolong the shelf-life of fruits. The multifunctional LCNF-WG coating and packaging displayed excellent barrier properties to oxygen (15.9 cm3 μm m−2 day−1 kPa−1) and water vapour (10.3 g mm−1 m−2 day−1) and excellent antimicrobial, UV blocking, water-resistant, reusable and recoverability performance, making it a promising economic alternative in food preservation with the natural-derived material. Moreover, the low cost and degradation ability of this natural-derived bio-nanocomposite are beneficial for producers, consumers, and the environment. [Display omitted] • LCNF played an important role in the colloidal stability performance. • LCNF-WG coatings and films show prominent preservation performance. • LCNF-WG films displayed excellent barrier properties to oxygen and water vapour. • LCNF-WG films displayed excellent antimicrobial, UV blocking, reusable performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • Phosphated lignocellulose nanofibrils were combined with MXene and gelatin; • The aerogel exhibited excellent fire retardancy with fire-warning performance; • Performance of electromagnetic interference shielding also achieved highly. Lightweight electromagnetic interference (EMI) shielding material with environment-friendly and high fire-safe has imperative practical significance in civil electronic devices. Herein, a distinct strategy was proposed to integrate phosphated lignocellulose nanofibrils (PLCNFs), gelatin, and MXene into a hybrid composite aerogel (PGM aerogel) with ultralight weight and high porosity. Due to the synergistic flame retardant effect of the ternary mixture, PGM aerogel exhibited excellent fire retardancy, whose dramatical changes in electronic resistance was supposed to achieve a short fire-warning signal (∼1 s). The limiting oxygen index (LOI) was as high as 32 % and the peak heat release rate (PHRR) was relatively as low as 30.1 W/g. Furthermore, the aerogel also displayed great specific EMI shielding effectiveness (SE) of SSE/t (14230 dB cm2 g−1) at 8.2 GHz. Therefore, this PGM aerogel can be a potential candidate in both EMI shielding and fire-warning fields. [ABSTRACT FROM AUTHOR]

A high-yield and straightforward method is proposed to obtain an electromagnetic interference (EMI) shielding film based on multilayered Ti 3 C 2 T x (m-Ti 3 C 2 T x). Holocellulose nanofibrils modified by sulfamic acid (SHCNF) with unique "core-shell" structure can act as a dispersant and a binder to assist in exfoliating m-Ti 3 C 2 T x into delaminated-Ti 3 C 2 T x (d-Ti 3 C 2 T x) and fabricate flexible Ti 3 C 2 T x /SHCNF composite films with a high-yield value. The "brick-and-mortar" composite films exhibit a superior electromagnetic interference (EMI) shielding effectiveness (SE) of 45.02 dB with an ultrathin thickness of 40 μm at the 12.4 GHz. Moreover, these flexible and strong integrated Ti 3 C 2 T x /SHCNF composite films also display excellent specific EMI SE of SSE/t (4437 dB cm2 g−1) and high EMI shielding efficiency (99.996%). Therefore, the SHCNF-assisted method provides a cost-effective approach to fabricate a strong and flexible MXene-based nanocomposite films toward EMI shielding application. [Display omitted] • Holocellulose nanofibrils assisted in exfoliating multilayered Ti 3 C 2 T x. • The Ti 3 C 2 T x /SHCNF film exhibited superior mechanical properties. • The film presented excellent specific EMI shielding efficiency. [ABSTRACT FROM AUTHOR]

Water-soluble cellulose ethers are widely used as stabilizers, thickeners, and viscosity modifiers in many industries. Understanding rheological behavior of the polymers is of great significance to the effective control of their applications. In this work, a series of cyanoethylcellulose (CEC) samples with different molecular weights were prepared with cellulose and acrylonitrile in NaOH/urea aqueous solution under the homogeneous reaction. The rheological properties of water-soluble CECs as a function of concentration and molecular weight were investigated using shear viscosity and dynamic rheological measurements. Viscoelastic behaviors have been successfully described by the Carreau model, the Ostwald-de-Waele equation, and the Cox–Merz rule. The entanglement concentrations were determined to be 0.6, 0.85, and 1.5 wt% for CEC-11, CEC-7, and CEC-3, respectively. All of the solutions exhibited viscous behavior rather than a clear sol-gel transition in all tested concentrations. The heterogeneous nature of CEC in an aqueous solution was determined from the Cox–Merz rule due to the coexistence of single chain complexes and aggregates. In addition, the CEC aqueous solutions showed good thermal and time stability, and the transition with temperature was reversible. [ABSTRACT FROM AUTHOR]

[Objectives] This study focused on interaction mechanism between H. rugaoensis/S. nematophila R187 complex and humoral immune system in Drosophila melanogaster infected by the nematode/bacteria complex. [Methods] Three methods, nematode with symbiotic bacteria strain HI87 infecting flies, needle-pricking the fly with the symbiotic bacterial strain R187 and feeding flies with symbiotic bacterium, were conducted to tranfer the bacterial strain H187 into hemocoel or intestine of flies. Lethal rate of flies and colonies statistic of symbiotic bacterium combined with Q-PCR detection of expression of the two antimicrobial peptides Diptericin and Drosomycin regulated respectively by Imd and Toll pathway were analyzed to recover the interaction between H. rugaoensis-S. nematodiphila R187 and the humoral immune system in D. melanogaster. The fly stocks used in this experiment were the wild type, FADD mutant( Imd) and Dif mutant (Toll). [Results] Infecting of H. rugaoensis with its symbiotic bacterial strain R187 or needle-pricking with the bacterial strain on flies could activate both the two humoral immune responses, Toll and Imd pathway. Results of fluorescence quantitative PGR detection showed that expression of Diptericin and Drosomycin in the two infecting methods had the same trend that up-regulated firstly and then gradually down-regulated. In the needle-pricking infection with symbiotic bacterium R187, the relative expression level of Drosomycin in FADD mutants was in the highest(100%)in 6 h, and those of Diptericin in Dif mutant and wild type were in the highest (90%) in 12 h. Only very weak expression of Diptericin and Drosomycin were detected in intestine infection of S. nematodiphila R187 on flies. All the three infecting methods could result in 100% lethal of flies. Lethal process of Dif mutant and wild type was similar, slowly than that of FADD mutants. Needle-pricking method had the highest infect efficency and caused 100% death of flies in 20 h. [ Conclusions] The rhahditid entomopathogenic nematode H. rugaoensis and its symbiotic bacterial strain S. nematophila R187 infected hemocoel of adult D. melanogaster together or separately could activate humoral immune responses of both Toll and Imd pathway in flies. Imd was the main immune response pathway for fly when faced with the infection of S. nematophila R187. There might be some immune escape mechanism to help S. nematodiphila R187 to infect flies successfully in the process of intestinal infection. [ABSTRACT FROM AUTHOR]

Liquid metal (LM) nanodroplets and MXene nanosheets are integrated with sulfonated bacterial nanocellulose (BNC) and acrylic acid (AA). Upon fast sonication, AA polymerization leads to a crosslinked composite hydrogel in which BNC exfoliates Mxene, forming organized conductive pathways. Soft conducting properties are achieved in the presence of colloidally stable core-shell LM nanodroplets. Due to the unique gelation mechanism and the effect of Mxene, the hydrogels spontaneously undergo surface wrinkling, which improves their electrical sensitivity (GF = 8.09). The hydrogels are further shown to display interfacial adhesion to a variety of surfaces, ultra-elasticity (tailorable elongation, from 1000 % to 3200 %), indentation resistance and self-healing capabilities. Such properties are demonstrated in wearable, force mapping, multi-sensing and patternable electroluminescence devices. [Display omitted] • Nanocellulose-supported LM/MXene composite hydrogels are formed by one-step sonication. • The polymer matrix effectively disperses core-shell LM nanodroplets and MXene nanosheets. • The hydrogels display ultra-elasticity, indentation resistance and self-healing properties. • The composite hydrogel is demonstrated for sensing, force mapping and electroluminescence. [ABSTRACT FROM AUTHOR]