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CCuO NM showed in-vitro anticancer potential against human cervical cancer cells (Hela) with an IC50 concentration of 34.69 μg/mL. Photoluminescence spectrum of CCuO NM showed a green emission (oxygen vacancies) observed at ∼516 nm, which is attributed to the generation of reactive oxygen species (ROS) by the nanomaterial, which is believed, to be responsible for the biocidal (cell death) effects. These results suggested that CCuO is a promising nanomaterial that could be suitable for advanced applications in the healthcare industries.This study reports the performance of FucoPol, a fucose-containing bacterial polysaccharide, as a photostable agent with high absorption yield at concentrations as low as 0.02 % (w/v). FucoPol is non-cytotoxic, efficiently protects from UVA and UVB at concentrations of 0.02-2 % (w/v) and 0.2-2 % (w/v), respectively, has over 94 % overall photostability up to 1.5 h of irradiation time. The lowest concentration studied (0.02 %, w/v) shows a sun protection factor (SPF) of 2.61 ± 0.08. The SPF-to-concentration unit ratio showed that FucoPol is about 60-fold more photoprotective than combinations of common organic and inorganic UV filters. In vitro radiation exposure experiments of adhered Vero epithelial and PM1 keratinocytic cells in the presence of 0.25 % (w/v) FucoPol further showed that cell viability was preserved, and delayed radiation-induced cell death was prevented. Overall, FucoPol outperforms common cosmetic biopolymers like xanthan and fucogel. These results are very promising for the development of bio-based sunscreen formulations.The simultaneous attainment of high strength and high toughness of transparent cellulose nanofibril (CNF) film can expedite its uses in advanced applications. In this work, a wood-inspired strategy is proposed to address the conflict between strength and toughness by using natural derived lignosulfonic acid (LA) as a reinforcing additive. Only 1 wt% LA addition can double the toughness (11.0±1.3 MJ/m3) of pure CNF film. Consequently, the as-prepared CNF/LA-1 nanocomposite film not only exhibits superior mechanical properties (23.6±1.3 MJ/m3 toughness, 249±6 MPa strength, and 15.4±1.4 % strain), but also maintains an excellent optical transparency of 91.2 % (550 nm). Furthermore, the mechanism for simultaneously enhancing strength and toughness is essentially attributed to the improved hydrogen bonding between CNF-OH and LA-SO3H and effective energy dissipation system. This work provides a green and effective approach to prepare strong yet tough and transparent biodegradable CNF film for high-end applications.This study examined the mechanism of swelling for high acyl (HA) gellan gum and the impacts on the hydrogel mechanical properties and the release of a model drug (glucose). Controlling the material properties and the release of entrapped drugs during use in aqueous environments, such as the stomach or bodily fluids, are crucial in designing functional applications. Swelling of HA gellan gum was controlled by varying the osmotic environment with salts and solvents, and effects on the gel network were characterized by uniaxial compression tests, DSC, and rheology. Low ionic strength solutions caused the greatest degree of swelling (up to 400 %) and corresponded to a more brittle gel with a greater modulus and greater network enthalpy. Swelling slowed the release of glucose by decreasing the diffusion flux. The osmotic environment was found to produce different functional properties, and it is crucial to consider these changes in the design of formulations.The poor water resistance of the eletrospun hyaluronic acid (HA) nanofibers prevents their biomedical applications. In this manuscript, we crosslinked HA nanofibers with the periodate oxidation - adipic acid dihydrazide (ADH) crosslinking strategy. Quantification results showed that ∼ 57 % of aldehydes in oxidized HA were crosslinked by ADH and the crosslinking density could reach 75.7 %. Correspondingly, the crosslinked HA nanofiber mats exhibited wet tensile strength up to 0.88 MPa and could maintain their nanofibrous morphology after 14 days in simulated body fluid. see more Although ∼ 28 % of the aldehydes in oxidized HA were unreacted, the crosslinked HA nanofibers did not cause toxicity to L929 fibroblast cells, possibly because that the unreacted aldehyde groups were linked on macromolecular fragments and could not go across cell membranes. The water resistant and biocompatible HA nanofibers are expected to seek extensive applications in biomedical fields such as wound healing, adhesion prevention, and tissue engineering.In order to find a facile and practical method to synthesize amino cellulose in bulk with high regional selectivity and high degree of substitution, the reaction conditions to brominate cellulose and to reduce azido group were carefully studied and some interesting phenomena were observed. With the optimized method, 6-amino-6-deoxy cellulose could be easily prepared with very simple separation techniques. The degree of substitution of the amino group amounted to 0.97 which was determined by 1H NMR spectrum of 6-benzamido-6-deoxy cellulose. Moreover, the amino group was evidenced to be at the C6 of glucose unit by 1H-1H COSY NMR and 1H-13C HSQC NMR spectra. In addition, three cellulose 6-acetamido-6-deoxy-2,3-bis(phenylcarbamate)s were prepared from the 6-amino-6-deoxy cellulose prepared with the techniques optimized in the present study. The developed cellulose derivatives were used as chiral selectors with which chiral stationary phases (CSPs) were prepared. The CSPs exhibited enantioseparation power to some chiral compounds.This study describes a two-step alkali/oxidation process to efficiently convert waste sugarcane bagasse (SCB) into cellulose nanofibrils (CNF) whose structures have been characterized using a range of analytical techniques (SR-WAXS, IR, TEM and DLS). Increasing the concentration of the NaOH solution from 10 to 16 wt% in the first step results in a gradual increase in cellulose II content from 0 to >99 %, which also produces a corresponding increase in fiber crystallinity index from 32 to 61 %. Varying the concentration of NaClO used in the second oxidative step enables the morphologies of the CNF to be reliably controlled, with fiber lengths decreasing from micrometer to nanometer levels as the amount of NaClO oxidant used is increased. This simple two-step alkaline/oxidative treatment process enables SCB to be converted into CNF exhibiting different polymorphic and morphological properties, thus enabling their economic and reproducible production as nanostructured materials for numerous applications.Cellulose acetate butyrate (CAB) belongs to cellulose esters, an important category of polymers, that are derived from the most abundant organic substance on earth (cellulose). As most cellulose esters, CAB is believed to exhibit a melting point. In this study, carefully selected experiments were performed, in order to test if the endothermic peak, observed in the Differential Scanning Calorimetry (DSC) scan of CAB, is a melting point. It was found that it is not a melting peak but a chemically induced transition (appearing as glass transition) occurring simultaneously with mass loss (decomposition and vaporization). For this phenomenon, the term "glass chemical transition" is proposed. Various literature misinterpretations/confusions are clarified and the potential consequences of this discovery are shortly discussed. Based on literature data and the presented results, it seems almost certain that secondary cellulose esters exhibit this behavior. It is likely, that other polymers, also exhibit this peculiar thermal transition.A new type of nanocellulose/poly(vinyl alcohol)/carbon dot (NPC) multifunctional hydrogel was successfully fabricated by an one-step in-situ hydrothermal method. The one-pot strategy led to the formation of a complex hydrogen bonding/dynamic boric acid ester/nitrogen-doped carbon dots network, and endowed the hydrogel with multifunctionality. The hydrogel underwent self-healing at room temperature (25 °C) and exhibited double-emission fluorescence and high mechanical strength (tensile strength of up to 2.98 MPa). An NPC hydrogel-based capacitive sensor exhibited remarkable linear capacitance responsiveness toward pressure, strain, and glucose concentration, and enabled real-time synchronous quantitative pressure/glucose sensing with multiple linear correlations, which was a key performance criteria for biomechanical sensors. The versatility and multiple advantages of the as-prepared hydrogel demonstrate the potential of biological-mechanical sensing materials using natural cellulosic biomass.The cellulose fibers with different size and aspect ratio was used as the matrix for the controllable preparation of zinc oxide (ZnO) to synthesize ZnO/cellulose composite catalyst with adjustable photocatalytic properties. The ZnO with different morphology of sphere, sheet, and flower, was in-situ synthesized on cellulose fibers by chemical deposition method, the flower-like ZnO supported on cellulose fiber exhibited the best photocatalytic activity. Furthermore, with the decrease of fiber size, the morphology of ZnO changed from most sheet to fully self-assembled flower shape, and the average thickness of nanosheets was increased. Cellulose fibers with smaller size and higher aspect ratio were more likely to form a 3D network structure with rich pores and stable mechanical properties. Significantly, with the decreasing of fiber size, ZnO/NFC has excellent photocatalytic efficiency (100 %). All ZnO/cellulose composites can be recycled more than five times.Porous cellulose acetate/carboxylated multiwalled carbon nanotubes (CA/OMWNTs) monolith with superhydrophobicity (155°) and superoleophilicity (∼0°) was first prepared using a facile and green phase separation method. Benefiting from the unique three-dimensional (3D) fiber cluster network structure, the as-prepared CA/OMWNTs monolith reveals a high porosity (93.7 %) and a large specific surface area (85.36 m2/g). As an oil adsorption material, the superhydrophobic porous monolith is able to adsorb the different kinds of organic solvents and oils from water efficiently and selectively with saturated adsorption capacities from 7.39 to 19.84 g g-1. Moreover, the porous monolith exhibits an excellent durability with the highly stable wettability and oil/water separation no matter at different pH (1-14) conditions or extreme temperatures (-20-160 °C). Besides, the CA/OMWNTs monolith also could continuously and rapidly separate oils/organic solvents from oil/water mixtures via a simple and home-made pump-assisted adsorption device, showing potential application in large-area remediation of oily wastewater.The mature basal stipe of mushroom Coprinopsis cinerea loses wall extensibility. We found that an endo-β-1,3-glucanase ENG from C. cinerea could restore mature basal stipe wall extensibility via pretreatment such that the ENG-pretreated basal stipe walls could be induced to extend by chitinase ChiIII. ENG pretreatment released glucose, laminaribiose, and 3-O-D-gentiobiose-D-glucose from the basal stipe walls, consistent with ENG-digested products of β-1,6-branched β-1,3-glucan. Different effects of endo-β-1,3-glucanase ENG and exo-β-1,3-glucanase EXG pretreatment on the structure, amount and ratio (β-1,3-glucoside bonds to β-1,6-glucoside bonds) of products from the basal stipe and the apical stipe cell walls, respectively, and on the cell wall extensibility and the cell wall ultra-architecture of the basal stipes were analyzed. All results demonstrate that the more accumulation and cross-linkage of β-1,6-branched β-1,3-glucan with wall maturation lead to loss of wall extensibility of the basal stipe regions compared to the apical stipe cell walls.