Carbohydrate Polymers最新文献

Bone regeneration is limited and generally requires external intervention to promote effective repair. Autografts, allografts, and xenografts as traditional methods for addressing bone defects have been widely utilized, their clinical applicability is limited due to their respective disadvantages. Fortunately, functional polysaccharide hydrogels have gained significant attention in bone regeneration due to their exceptional drug-loading capacity, biocompatibility, and ease of chemical modification. They also provide an optimal microenvironment for bone repair and regeneration. This review provides an overview of various functional polysaccharide hydrogels derived from biocompatible materials, focusing on their applications in intelligent delivery systems, bone tissue regeneration, and cartilage defect repair. Particularly, the incorporation of bioactive molecules into the design of functional polysaccharide hydrogels has been shown to significantly enhance bone regeneration. Additionally, this review emphasizes the preparation methods for functional polysaccharide hydrogels and associated the bone healing mechanisms. Finally, the limitations and future prospects of functional polysaccharide hydrogels are thoroughly evaluated.

The reduction in hyaluronic acid concentration and viscosity in the synovial fluid of patients struggling with osteoarthritis increases the abrasion of articular cartilage. The aim of this study was to design a semi-IPN hydrogel based on genipin-crosslinked carboxymethyl chitosan (CMCh) and glycerol to achieve long-term release of hyaluronic acid. The results showed that hydrogel comprising CMCh (3 % wt.), HA (0.3 % wt.), and glycerol (1.25 % wt.), with high structural sustainability (over 45 % within 30 days of exposure to PBS/lysozyme medium), swelling ratio of 368.6 %, compression modulus of 8.4 kPa, elongation at break of 64.4 %, and cell viability of >90 % (in 48 h exposure), provides a long retention time and release of HA, which leads to gradual absorption, minimizes pain, and maintains joint mobility, as well as preventing multiple injections. The non-Newtonian behavior of the hydrogel (before crosslinking) along with the favorable gelation time help the viscosupplement to be easily injected and then maintain its position till the end of the crosslinking process within 18min. Considering all the data obtained, it is hypothesized that the optimum sample, namely CHG4Gly1.25, resulting in excellent injectability and moldability, can serve as a novel and promising substrate for biomaterial applications.

The contamination of water resources by selenium (Se), particularly in the highly toxic Se(IV) oxidation state, poses a significant environmental and public health concern due to its detrimental impacts on humans and aquatic ecosystems. In this work, we report a novel composite foam (CFC) by incorporating chitosan (CS), cellulose nanofibers (CNF) and iron oxyhydroxide (FeOOH) nanoparticles through a one-pot fabrication process. The CFC foam features a three-dimensional porous structure, conferring both exceptional mechanical strength and superior adsorption performance for Se(IV), with a maximum equilibrium adsorption capacity of 90 mg/g achieved within 3 h. It maintained stable removal efficiency across a wide pH range and demonstrated strong resistance to interference from common anions and ionic strength variations. The primary adsorption mechanism involves electrostatic interactions and complexation between Se(IV) and functional groups presented in the CFC foam. Molecular dynamics simulations further confirmed the stability and effectiveness of Se(IV) adsorption at the molecular level. Additionally, CFC foam exhibited satisfactory practical applicability and durability, maintaining high Se(IV) removal performance over sequential adsorption processes. This study highlights the potential of CFC foam as an effective and sustainable material for Se(IV) remediation in wastewater, offering a promising solution for mitigating Se pollution and improving water quality.

Physical, chemical, and dual modifications can all significantly affect the digestibility of isolated rice granules, while their effects on the starch digestibility of whole cooked rice grains remain elusive. Therefore, the impact of malic acid, ultrasound, and ultrasound + malic acid dual treatment on the starch digestibility of cooked rice grains with different starch molecular structures was investigated in this study. Ultrasound mainly caused cavitation on the surface of rice grains, promoting the leaching of materials (> 11 %) and amylose during cooking. This led to a faster retrogradation rate, smaller pores, and a lower maximum starch digestion extent. In contrast, malic acid caused a faster digestion rate due to the significant degradation of starch molecules, although its moderate esterification smoothed the cooked rice grain surface and slightly reduced the maximum starch digestion extent. Compared to malic acid treatment, the dual treatment showed a much higher degree of esterification, which may thus contribute to its significantly lower maximum starch digestion extent (up to 21 %). Collectively, these findings suggest that both ultrasound and dual treatment can be effective strategies for producing cooked rice grains with slower starch digestibility, with implications for improving the public health.

This study focuses on the fabrication of 3D-printed chitosan/Ti₃C₂T_x-MXene aerogels with varying MXene concentrations (1, 2, 5, and 10 wt%) using the direct ink writing (DIW) method. The inks were freeze-dried to form aerogels, and FTIR and XRD analyses confirmed interactions between chitosan and MXene molecules, leading to increased spacing between MXene nanosheets. Rheological testing showed improved shear-thinning behavior, enhancing printability. A higher MXene content boosted the electrical conductivity, dielectric properties, and electromagnetic interference (EMI) shielding effectiveness, with the 10 wt% MXene aerogel achieving an EMI shielding effectiveness of 27 dB. The thermal conductivity initially decreased but later increased with higher MXene concentrations. Mechanical tests indicated enhanced Young's modulus and tensile strength with more MXene, but the elongation at break decreased. The printed aerogels were used in a Triboelectric Nanogenerator (TENG), showing an increase in output voltage from 22 V for pure chitosan aerogels to 110 V for 2 wt% MXene, with a slightly lower increase in current. However, exceeding 2 wt% MXene led to reduced performance. This study highlights the potential of printed aerogels for energy harvesting, EMI shielding, and thermal insulation applications.

Ancient documents and artworks are invaluable cultural heritage artworks that require careful preservation. Traditional methods for assessing their physical and chemical properties-such as tearing index, tensile index, water absorption, and pH-are often destructive, risking irreversible damage. This study introduces a novel, non-destructive approach using Short-Wave Near-Infrared (SWNIR) hyperspectral imaging (HSI) combined with advanced machine learning models. By integrating spectral preprocessing, feature selection, and machine learning techniques-including Back Propagation Neural Networks (BPNN), Long Short-Term Memory Networks (LSTM), and Convolutional Neural Networks (CNN)-with Sparrow Search Algorithm (SSA) optimization and Gray Level Co-occurrence Matrix (GLCM) texture feature extraction, the resulting SSA-BP-UVE-GLCM model achieved high predictive accuracy (R² ≥ 0.98). This framework enables precise, pixel-level predictions of paper properties, influenced by polysaccharides like cellulose, offering a non-invasive analysis that supports targeted restoration strategies and advances the conservation of cultural heritage. The findings enhance non-invasive testing and classification methods for polysaccharide-based materials, providing a foundation for further exploration of environmental impacts on artwork integrity using sophisticated machine learning algorithms.

Schizophyllan (SPG) is a semi-flexible, triple-helical polysaccharide with attractive properties as an efficient viscosifying compound and biological response modifier. We report microrheological characterization of schizophyllan as dispersed in solution and the changes associated when crosslinked with chitosan over an extended frequency range using diffusing wave spectroscopy (DWS). A SPG with high molecular weight (M_w = 1.1 × 10⁶ Da) was selectively oxidized in the side chains (20 % or 40 %) to promote Schiff base formation with chitosan (CHI) amine groups, thus inducing crosslinking. The microrheological characterization of the dispersed SPG revealed characteristic features of the semiflexible structure, where also coupling between flexure and longitudinal modes was indicated based on scaling coefficient close to 7/8 of the loss modulus G"(ω) vs ω for ω in the range 3 × 10³-10⁵ rad/s. The in-situ characterization of the gelation process by DWS revealed changes in the scattered intensity-correlation function caused by the embedded colloidal probe-particles, from which the mean-square displacement of the probes and the shear moduli of the SPG-chitosan hydrogel samples were determined for various SPG concentrations and degrees of oxidation. It is found that SPG - chitosan hydrogels can be prepared with a polymer content in the range of 0.5-2.0 mg/mL and that tuning the molecular parameters allowed control of mechanical moduli in soft hydrogels in the range of 0.3 Pa up to 1000 Pa.

The extraction of polysaccharides from wood by-products is recognized as a green re-utilization approach to shape a recycling-oriented society. In this research, we identified the structural properties of arabinogalactan (AG) extracted from Larix sibirica Ledeb wood chips and verified its efficacy as an additive in broiler framing. Results showed that the molecular weight of AG is 19.805 KDa. Methylation analysis and NMR spectra indicate that AG has a 1,6-linked Galp backbone, side residues mainly branched at C-1,3,6 on β-D-Galp. The Ara residues were substituted at C-3 of 1,6-linked Galp consisting of α-L-Araf-(1→3)-α-L-Araf-(1 → 3)-α-L-Araf (1→ and α-L-Araf-(1 → 4) β-D-Galp-(1 → 3)-β-D-Galp-(1→. As a dietary supplement in broiler model, AG treatment improved the body weight of broilers especially breast and leg muscle weight. Furthermore, AG could regulate host immune response, gut microbiota composition, and metabolic activity, especially promoting lipid metabolism. By means of serum non-targeted metabolomics analysis, enrichment of pantothenate and CoA biosynthesis and beta-alanine metabolism pathways could be determined. AG treatment led to a rise in bacteria that produce SCFAs, with elevated concentrations of acetic and butyric acids. In conclusion, AG can be considered as a potential dietary supplement to beneficially affect host's health status.

The convenience, versatility, and biocompatibility of photocrosslinkable hydrogel precursors make them promising candidates for developing tissue engineering scaffolds. However, the current library of photosensitive materials is limited. This study reports, for the first time, the modification of quince seed mucilage (QS) with glycidyl methacrylate (GM), resulting in the synthesis of methacrylated QS (QSGM). The chemical composition and structure of QS were analyzed. The effects of reaction time, temperature, QS concentration, and GM/QS ratio on the degree of methacrylation, as well as the physicochemical, rheological, mechanical, and biological properties of the synthesized materials were explored. Chemical characterization using ¹H NMR and FTIR confirmed the successful methacrylation of QS. Hydrogels fabricated from QSGMs at a 0.5 wt% concentration exhibited high swelling ratios of 320 to 580 g/g, and compressive strengths between 0.6 ± 0.1 and 1.2 ± 0.3 kPa. No significant changes in the rheological properties of hydrogel precursors were observed. Moreover, QSGM-based hydrogels supported cell encapsulation for 14 days with minimal cytotoxicity and immune cell activation. Finally, as a proof of concept, the potential use of QSGM for 3D printing was demonstrated. Overall, the results highlight the significant potential of QSGMs as a biomaterial of choice for soft tissue engineering applications.

Lignocellulosic biomass-based plastics provide a sustainable alternative to petroleum-based plastics by converting agricultural by-products into value-added materials, promoting a circular economy. This study investigates the development of thermoplastics from sugar beet pulp (SBP), a by-product rich in cellulose and pectin. A one-pot direct transesterification process was used to fully substitute hydroxy groups in SBP with acyl chains of varying lengths (C2-C10), achieving up to 96 % substitution. The thermal and mechanical properties of SBP esters were analyzed without fractionating polysaccharides. SBP esters exhibited excellent melt flow properties, making them suitable for injection molding applications. The presence of pectin influenced the thermal behavior of the materials; the removal of pectin increased the flow temperature from 155.7 to 204.6 °C. These findings highlight the potential of SBP esters as sustainable plastics, offering a pathway to convert agricultural by-products into high-value materials, thus contributing to a circular economy.