Carbohydrate Polymers

Designing advanced functional cellulose-based materials by one-step homogeneous preparation technology is a great challenge since cellulose is insoluble in common solvents or difficult to regenerate and shape. Quaternized cellulose beads (QCB) were prepared from a homogeneous solution by one-step cellulose quaternization homogeneous modification and macromolecules' reconstruction technology. Morphological and structural characterizations of QCB were conducted by SEM, FTIR and XPS, etc. The adsorption behavior of QCB was studied using amoxicillin (AMX) as a model molecule...

A novel hydroxypropyl cellulose (gHPC) hydrogel with graded porosity has been fabricated, in which pore size, shape, and mechanical properties vary across the material. The graded porosity was achieved by cross-linking different parts of the hydrogel at temperatures below and above 42 °C, which was found to be the temperature of turbidity onset (lower critical solution temperature, LCST) for the HPC and divinylsulfone cross-linker mixture. Scanning electron microscopy imaging revealed a decreasing pore size along the cross-section of the HPC hydrogel from the top to the bottom layer...

Lightweight and highly compressible materials have received considerable attention in flexible pressure sensing devices. In this study, a series of porous woods (PWs) are produced by chemical removal of lignin and hemicellulose from natural wood by tuning treatment time from 0 to 15 h and extra oxidation through H2 O2 . The prepared PWs with apparent densities varying from 95.9 to 46.16 mg/cm3 tend to form a wave-shaped interwoven structure with improved compressibility (up to 91.89 % strain under 100 kPa)...

The development of photothermal materials with high photothermal-conversion efficiencies is important in a range of applications, such as power generation, sterilization, desalination, and energy-production. To date, a few reports have been published related to improving the photothermal conversion performances of photothermal materials based on self-assembled nanolamellae. Herein, hybrid films of co-assembled stearoylated cellulose nanocrystals (SCNCs) and polymer-grafted graphene oxide (pGO)/polymer-grafted carbon nanotubes (pCNTs) were prepared...

Biological macromolecules had been studied as ligands in recent years, which not only give the complexes excellent polymer properties, but also have many advantages such as biodegradability. Carboxymethyl chitosan (CMCh) is excellent biological macromolecular ligand because of its abundant active amino and carboxyl groups, and it can smoothly transfer energy to Ln3+ after coordinating. To further study the energy transfer mechanism of CMCh-Ln3+ complexes, CMCh-Eu3+ /Tb3+ complexes with different Eu3+ /Tb3+ ratios were prepared by using CMCh as a ligand...

Herein, imidazole acids grafted chitosan derivatives were synthesized, including HACC, HACC derivatives, TMC, TMC derivatives, amidated chitosan and amidated chitosan bearing imidazolium salts. The prepared chitosan derivatives were characterized by FT-IR and 1 H NMR. The tests evaluated the biological antioxidant, antibacterial, and cytotoxic activities of chitosan derivatives. The antioxidant capacity (DPPH radical, superoxide anion radical and hydroxyl radical) of chitosan derivatives was 2.4-8.3 times higher than that of chitosan...

Granular macroscopic chitosan/carboxymethylcellulose polyelectrolytic complexes (CHS/CMC macro-PECs) were produced and tested as adsorbents for six pollutants often present in wastewaters: sunset yellow (YS), methylene blue (MB), Congo red (CR) and safranin (S), cadmium (Cd2+ ) and lead (Pb2+ ). The optimum adsorption pH values at 25 °C were 3.0, 11.0, 2.0, 9.0, 10.0, and 9.0 for YS, MB, CR, S, Cd2+ , and Pb2+ , respectively. Kinetic studies indicated that the pseudos-econd order model best represented the adsorption kinetics of YS, MB, CR, and Cd2+ , whereas the pseudo-first order model was the most suitable for S and Pb2+ adsorption...

Binary and ternary blends with poly(lactic acid) (PLA), poly(butylene succinate) (PBS), and thermoplastic starch (TPS) were prepared by a melt process to produce biodegradable biomass plastics with both economical and good mechanical properties. The mechanical and structural properties of each blend were evaluated. Molecular dynamics (MD) simulations were also conducted to examine the mechanisms underlying the mechanical and structural properties. PLA/PBS/TPS blends showed improved mechanical properties compared with PLA/TPS blends...

Cancer therapy continues to be a major global concern, with conventional treatments suffering from low efficacy, untargeted drug delivery, and severe side effects. Recent research in nanomedicine suggests that nanoparticles' unique physicochemical properties can be leveraged to surmount the limitations of conventional cancer treatment. Chitosan-based nanoparticles have gained significant attention due to their high drug-carrying capacity, non-toxicity, biocompatibility, and long circulation time. Chitosan is utilized in cancer therapies as a carrier to accurately deliver active ingredients to tumor sites...

In this study, chitosan-gelatin conjugates were prepared by chemical crosslinking of tannic acid. The cryogel templates were developed through freeze-drying and immersed in camellia oil to construct cryogel-templated oleogels. Chemical crosslinking resulted in apparent colour changes and improved emulsion-related/rheological properties on conjugates. The cryogel templates with different formulas exhibited different microstructures with high porosities (over 96 %), and crosslinked samples might have higher hydrogen bonding strength...

Uranium mining, smelting, and nuclear industries generate a considerable amount of wastewater containing uranium. To treat this wastewater effectively and inexpensively, a novel hydrogel material (cUiO-66/CA) was developed by co-immobilizing UiO-66 with calcium alginate and hydrothermal carbon. Batch tests were conducted to determine the optimal adsorption conditions for uranium using cUiO-66/CA, and the adsorption behavior was spontaneous and endothermic, confirming the quasi-second-order dynamics model and the Langmuir model...

Deciphering the determinants of starch digestion from multiple interrelated properties is a challenge that can benefit from multifactorial data analysis. The present study investigated the digestion kinetic parameters (rate, final extent) of size-fractions from four commercial wheat starches with different amylose contents. Each size-fraction was isolated and characterized comprehensively using a large range of analytic techniques (FACE, XRD, CP-MAS NMR, time-domain NMR, DSC…). A statistical clustering analysis applied on the results revealed that the mobility of water and starch protons measured by time-domain NMR was consistently related to the macromolecular composition of the glucan chains and to the ultrastructure of the granule...

Cyanidin 3-O-glucoside (CND) is a frequently-used anthocyanin that has excellent antioxidant properties but a limited bioavailability in bloodstream. Complexation of CND with alginate can improve its therapeutic outcome. Here we have studied the complexation of CND with alginate under a range of pH values from 2.5 to 5. CND is positively charged at low pH, and becomes neutral, and then negatively charged as pH increases. CND/alginate complexation was studied by dynamic light scattering, transmission electron microscopy, small angle X-ray scattering, STEM, UV-Vis spectroscopy and circular dichroism (CD)...

Conductive hydrogels have attracted widespread attention because of their integrated characteristics of being stretchable, deformable, adhesive, self-healable, and conductive. Herein, we report a highly conductive and tough double-network hydrogel based on a double cross-linked polyacrylamide (PAAM) and sodium alginate (SA) network with conducting polypyrrole nanospheres (PPy NSs) uniformly distributed in the network (PAAM-SA-PPy NSs). SA was employed as a soft template for synthesis of PPy NSs and distribution of PPy NSs uniformly in the hydrogel matrix to construct SA-PPy conductive network...

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...

Valorization of underutilized biobased feedstocks like hetero-polysaccharides is critical for the development of the biorefinery concept. Towards this goal, highly uniform xylan micro/nanoparticles with a particle size ranging from 400 nm to 2.5 μm in diameter were synthesized by a facile self-assembly method in aqueous solutions. Initial concentration of the insoluble xylan suspension was utilized to control the particle size. The method utilized supersaturated aqueous suspensions formed at standard autoclaving conditions without any other chemical treatments to create the resulting particles as solutions cooled to room temperature...

Although many polysaccharides utilization loci (PULs) have been investigated by genomics and transcriptomics, the detailed functional characterization lags severely behind. We hypothesize that PULs on the genome of Bacteroides xylanisolvens XB1A (BX) dictate the degradation of complex xylan. To address, xylan S32 isolated from Dendrobium officinale was employed as a sample polysaccharide. We firstly showed that xylan S32 promoted the growth of BX which might degrade xylan S32 into monosaccharides and oligosaccharides...

Peripheral nerve repair following injury is one of the most serious problems in neurosurgery. Clinical outcomes are often unsatisfactory and associated with a huge socioeconomic burden. Several studies have revealed the great potential of biodegradable polysaccharides for improving nerve regeneration. We review here the promising therapeutic strategies involving different types of polysaccharides and their bio-active composites for promoting nerve regeneration. Within this context, polysaccharide materials widely used for nerve repair in different forms are highlighted, including nerve guidance conduits, hydrogels, nanofibers and films...

Hybrid LiMg batteries stand out by combining the rapid lithium diffusion kinetics and the advantages of magnesium. However, the uneven Mg deposits may result in continuous parasitic reactions and penetrate the separator. Herein, cellulose acetate (CA), with functional groups, was applied to engineer coordination with MOFs and construct the evenly-distributed and ample nucleation sites. Moreover, the hierarchical [email protected] network was fabricated via the metal ion pre-anchored strategy to regulate the uniform Mg2+ flux and improve ion-conductivity simultaneously...

The polysaccharide in solution at critical concentration, Cc (g/L), is assimilated to a nano hydrogel (nHG) made of a single polysaccharide chain. Taking as reference the characteristic temperature of 20 ± 2 °C at which kappa-carrageenan (κ-Car) nHG swelling is greater with a Cc = 0.55 ± 0.05 g/L, the temperature of the minimum deswelling in the presence of KCl was found at 30 ± 2 °C for 5 mM with a Cc = 1.15 ± 0...