Search Results (394)

The morphology and composition of inorganic particles play a vital role in controlling the flame-retardant characteristics of polymers. Halogen-free flame-retardant polymers have also become a current research hotspot. Boron nitride (BN), phytic acid (PA), and chitosan (CS), a natural polysaccharide with a nitrogen content of approximately 6.8–7.5%, show great promise as flame retardants owing to their high thermal stability, P-based flame retardancy, and natural polysaccharide properties, respectively. In this study, BN (BN@PA-CS) particles coated with PA and CS were designed and prepared via a facile modification strategy. The effect of BN@PA-CS on the mechanical and flame-retardant properties of polyvinylidene fluoride (PVDF) was further investigated, and it was found that both characteristics were improved. Compared to pure PVDF, the PVDF composite films exhibited a significantly lower peak heat release rate and total heat release. With a BN@PA-CS content of 20%, the peak was the lowest at 18.25 W/g, corresponding to a decrease of 77.83%. This phenomenon may be attributed to the synergistic effect of the BN nanosheets and PA-CS in the BN@PA-CS particles. This work describes a facile and effective method of modifying the morphology and composition of inorganic particles, thereby controlling the properties of polymers, and provides a new approach to improving the safety of PVDF battery separators. Full article

The fields of healthcare and pharmaceutical science are increasingly focused on developing innovative and effective treatments. This trend is driven by a growing consumer demand for natural, sustainable, and highly functional polymer-based products. This study focuses on two biomaterials: chitosan and royal jelly. Chitosan, a linear polysaccharide derived from chitin, is well-regarded for its hemostatic and antimicrobial properties, making it an excellent candidate for wound healing applications. Royal jelly, a nutrient-rich secretion from honeybees, represents a complex mixture of proteins, lipids, vitamins, and antioxidants, notably 10-hydroxy-2-decenoic acid (10-H2DA). It is known for its anti-inflammatory, antioxidant, and regenerative effects on the skin. While the individual benefits of chitosan and royal jelly are well-documented, there is a significant research gap concerning their synergistic application in various treatments such as topical formulations, wound healing, regenerative medicine, and delivery transport processes. Ultimately, this review concludes that the synergistic effects of chitosan and royal jelly could provide a material platform with a superior dual-action profile, integrating the structural and antimicrobial benefits of chitosan with the powerful regenerative and anti-inflammatory effects of royal jelly. This synergy strongly supports their utility in developing next-generation, high-performance natural bioproducts for wound healing, bone regeneration, agriculture, or aquaculture applications. Full article

The shift towards renewable resources has positioned agar, a natural seaweed polysaccharide, as a pivotal and sustainable material for developing next-generation energy storage technologies. This review highlights the transformative role of agar-based composites as a game-changing and eco-friendly platform for supercapacitors, batteries, and fuel cells. Moving beyond the traditional synthetic polymers, agar introduces a novel paradigm by leveraging its natural gelation, superior film-forming ability, and inherent ionic conductivity to create advanced electrolytes, binders, and matrices. The novelty of this field lies in the strategic fabrication of synergistic composites with polymers, metal oxides, and carbon materials, engineered through innovative techniques like electrospinning, solvent casting, crosslinking, 3D printing, and freeze-drying. We critically examine how these innovative composites are breaking new ground in enhancing device efficacy, flexibility, and thermal stability. Ultimately, this analysis not only consolidates the current landscape but also charts future pathways, positioning agar-based materials as a pivotal and sustainable solution for powering the future. Full article

Cellulose, the most abundant polysaccharide on earth, possesses desirable properties such as biodegradability, low cost, and low toxicity, making it suitable for a wide range of applications. Being a non-conductive material, the structure of the nanocellulose can be modified or incorporated with conductive filler to facilitate charge transport between the polymer matrix and conductive components. Recently, cellulose-based ion exchange membranes (IEMs) have gained strong attention as alternatives to environmentally burdening synthetic polymers in electrochemical energy systems, owing to their renewable nature and versatile chemical structure. This article provides a comprehensive review of the structures, fabrication aspects and properties of various cellulose-based membranes for fuel cells and water electrolyzers, batteries, supercapacitors, and reverse electrodialysis (RED) applications. The scope includes an overview of various cellulose-based membrane fabrication methods, different forms of cellulose, and their applications in energy conversion and energy storage systems. The review also discusses the fundamentals of electrochemical energy systems, the role of IEMs, and recent advancements in the cellulose-based membranes’ research and development. Finally, it highlights current challenges to their performance and sustainability, along with recommendations for future research directions. Full article

In recent years, apatite-based materials have garnered significant interest, particularly for applications in tissue engineering. Apatite is most commonly employed as a coating for metallic implants, as a component in composite materials, and as scaffolds for bone and dental tissue regeneration. Among its various forms, hydroxyapatite (HAP) is the most widely used, owing to its natural occurrence in human and animal hard tissues. An emerging area of research involves the use of fluoride-substituted apatite, particularly fluorapatite (FAP), which can serve as a direct fluoride source at the implant site, potentially offering several biological and therapeutic advantages. However, substituting HAP with FAP may lead to unforeseen changes in material behavior due to the differing physicochemical properties of these two calcium phosphate phases. This study investigates the effects of replacing hydroxyapatite with fluorapatite in ceramic–polymer composite materials incorporating β-1,3-glucan as a bioactive polymeric binder. The β-1,3-glucan polysaccharide was selected for its proven biocompatibility, biodegradability, and ability to form stable hydrogels that promote cellular interactions. Nitrogen adsorption analysis revealed that FAP/glucan composites had a significantly lower specific surface area (0.5 m²/g) and total pore volume (0.002 cm³/g) compared to HAP/glucan composites (14.15 m²/g and 0.03 cm³/g, respectively), indicating enhanced ceramic–polymer interactions in fluoride-containing systems. Optical profilometry measurements showed statistically significant differences in profile parameters (e.g., Rp: 134 μm for HAP/glucan vs. 352 μm for FAP/glucan), although average roughness (Ra) remained similar (34.1 vs. 27.6 μm, respectively). Microscopic evaluation showed that FAP/glucan composites had smaller particle sizes (1 μm) than their HAP counterparts (2 μm), despite larger primary crystal sizes in FAP, as confirmed by TEM. XRD analysis indicated structural differences between the apatites, with FAP exhibiting a reduced unit cell volume (524.6 ų) compared to HAP (528.2 ų), due to substitution of hydroxyl groups with fluoride ions. Spectroscopic analyses (FTIR, Raman, ³¹P NMR) confirmed chemical shifts associated with fluorine incorporation and revealed distinct ceramic–polymer interfacial behaviors, including an upfield shift of PO₄³⁻ bands (964 cm⁻¹ in FAP vs. 961 cm⁻¹ in HAP) and OH vibration shifts (3537 cm⁻¹ in FAP vs. 3573 cm⁻¹ in HAP). The glucan polymer showed different hydrogen bonding patterns when combined with FAP versus HAP, as evidenced by shifts in polymer-specific bands at 888 cm⁻¹ and 1157 cm⁻¹, demonstrating that fluoride substitution significantly influences ceramic–polymer interactions in these bioactive composite systems. Full article

Hybrid polysaccharide-based aerogels offer significant potential as advanced drug delivery platforms due to their tunable structure, high porosity, and biocompatibility. In this study, aerogel microparticles were synthesized using alginate, pectin, carrageenan, and their hybrid formulations via an emulsion–gelation technique followed by supercritical fluid CO₂ extraction. The resulting aerogels exhibit mesoporous structures with specific surface areas ranging from 324 to 521 m²/g and pore volumes between 1.99 and 3.75 cm³/g. Comprehensive characterization (SEM, gas sorption, XRD, TGA, DSC, and FTIR) confirmed that hybridization improved morphological uniformity and thermal stability compared to single polymer aerogels. Ibuprofen was used as a model drug to evaluate loading efficiency and release kinetics. Among all formulations, the alginate/carrageenan (2:1) hybrid showed the highest drug loading efficiency (93.5%) and a rapid release profile (>90% within 15 min), closely matching the performance of commercial ibuprofen tablets. Drug release followed Fickian diffusion, as confirmed by the Korsmeyer–Peppas model (R² > 0.99). These results highlight the potential of hybrid polysaccharide aerogels as vehicles for drug delivery and other fast-acting therapeutic applications. Full article

Hyaluronan (HA), a high-molecular-weight polysaccharide naturally found in vertebrate tissues such as skin, joints, and the vitreous body, plays a critical role in various biological processes. Its functionality is highly dependent on molecular weight, with high-molecular-weight HA exhibiting anti-inflammatory and immunosuppressive effects, while low-molecular-weight HA promotes inflammation, immunostimulation, and angiogenesis. Due to its biocompatibility, biodegradability, and tunable properties, HA has gained increasing attention in biomedical applications. This review summarizes recent advances in the encapsulation of HA with other polymers and therapeutic agents in nanosystems, particularly hydrogels and nanoparticles. HA-based formulations demonstrate improved therapeutic outcomes, including drug release sustained up to 7 days, wound closure rates exceeding 90% in animal models, particle size in the range of 50–300 nm, and enhanced bioavailability of encapsulated drugs by 2–3 fold compared with free drugs. Such properties have shown promise in enhancing therapeutic efficacy and targeted drug delivery in the treatment of skin wound healing, diabetes, osteoarthritis, rheumatoid arthritis, and ophthalmic diseases. The review emphasizes how HA’s modifications and composite systems optimize drug release profiles and biological interactions, thereby contributing to the development of next-generation biomedical therapies. Full article

This review overviews the efficient hydrophobization method of hydrophilic natural polymers, which has been developed by means of glucan phosphorylase (GP)-induced enzymatic grafting of unnatural heteropolysaccharides, that is, partially 2-deoxygenated (P2D)-amyloses. The enzymatic polymerization technique is well known as a useful approach to prepare polysaccharides with well-defined structures. The authors have found that the hydrophobicity of P2D-amylose, synthesized by the thermostable GP (from Aquifex aeolicus VF5)-induced enzymatic copolymerization of α-d-glucose 1-phosphate (Glc-1-P)/d-glucal as comonomers, started from maltooligosaccharide primers. Based on this finding, glycogen, a hydrophilic spherical natural polysaccharide, was hydrophobized by means of the thermostable GP-induced enzymatic functionalization of the P2D-amylose chains because glycogen acted as the polymeric primer for the GP catalysis. After introducing the maltooligosaccharide primers onto hydrophilic natural polymers with carboxylate groups—such as poly(γ-glutamic acid), carboxymethyl cellulose, and alginic acid—via chemical reactions, the thermostable GP-induced enzymatic copolymerization of Glc-1-P/d-glucal was carried out using the resulting polymeric primers, enabling their hydrophobization through the grafting of P2D-amylose chains (the chemoenzymatic approach). Moreover, the chemoenzymatic method has extensively been employed for hydrophobization of the surfaces on natural polysaccharide nanofibers, such as cellulose and chitin nanofibers. Full article

Current food packaging, primarily made of non-biodegradable plastics, significantly contributes to environmental pollution. New packaging systems for food applications from biopolymers and/or with multifunctional properties are being developed as substitutes for synthetic polymers. The increasing concern over the environmental effects of packaging waste is driving a transition toward renewable packaging materials. Edible films and coatings play a vital role in maintaining food quality by preventing the loss of aroma, flavour, and important components, while also extending shelf life. Biopolymers, including polysaccharides, proteins, and lipids, are gaining attention as the future of packaging due to the environmental issues linked to petrochemical-based plastics. Modern packaging should not only protect products but also be biodegradable, recyclable, and have a minimal ecological impact. This review comprehensively summarises edible packaging in the form of single-use, fast-dissolving pouches for food applications as a circular approach and a sustainable solution in food technology. Innovations have resulted in the development of a unique packaging solution made from renewable sources. This packaging utilises plant and animal by-products to create edible films and pouches that are easy to seal. Edible packaging is emerging as a sustainable alternative, designed to simplify food packaging while minimising waste. Fast-dissolving scalable packaging, particularly edible films that dissolve in water, is used for individual servings of dry foods and instant beverages. This includes items like breakfast cereals, instant coffee or tea, and various powdered products. Additionally, there is an innovative approach to single-use packaging for oils and powders, leveraging the convenience and efficiency of these fast-dissolving films. Edible pouch packaging, made from safe and edible materials, provides a biodegradable option that decomposes naturally, thereby reducing pollution and the need for disposal. Full article

Cellulose aerogel is a promising thermal insulation material with terrific thermal insulation and environmental friendliness. However, the intrinsic flammability of polysaccharide molecules and dependence on freeze-drying have limited its application in flame-retardant and thermal management systems. Here, we develop a flame-retardant biomass aerogel based on a dual-network matrix of bacterial cellulose and sodium alginate. This innovative material enables high-efficiency and low-cost preparation via ambient pressure drying technology (only ~3.5% volume shrinkage), while achieving flame retardancy by introducing an inorganic nanosheet microstructure within a polymer matrix. The resulting dual-network flame-retardant cellulose aerogel demonstrates thermal performance superior to that of most polymer foams and conventional cellulose aerogels, featuring an ultra-low thermal conductivity of ~0.04 W m⁻¹ K⁻¹ and a high limiting oxygen index (LOI) of ~69%. This research provides a novel strategy for simultaneous flame-retardant modification and energy-efficient manufacturing of biomass-derived aerogels. Full article

Tomato fruit is susceptible to decay caused by Colletotrichum gloeosporioides. An edible coating derived from essential oils loaded into a chitosan polysaccharide polymer is a sustainable delivery approach to improve coating versatility and stability for reduced reliance on synthetic fungicides to combat anthracnose incidence in tomatoes. The objective of this study was to evaluate the antifungal efficacy of nanostructured thyme essential oil incorporated into chitosan coatings [Nano-(T)-EO-CS] against Colletotrichum gloeosporioides in tomato fruits, and to investigate the underlying mechanisms contributing to its inhibitory effects. Nano-(T)-EO of (1% v/v) showed the greatest antifungal activities while achieving complete inhibition of C. gloeosporioides. At (0.8% w/v) concentration, chitosan inhibited 78% of radial mycelial growth in C. gloeosporioides. Loading Nano-(T)-EO (1% v/v) into chitosan (0.8% w/v) completely inhibited spore germination (100%). The surface electron microscopy revealed that the Nano-(T)-EO-CS coating induced significant deformation and inhibited the growth of C. gloeosporioides. Compared with the control, the Nano-(T)-EO-CS coating reduced disease incidence by 50%, whereas the commercial antifungal agent Sporekill^® reduced incidence by 40% in preventively inoculated tomatoes stored at 10 °C and 85% relative humidity (RH) for 14 days after harvest, and at 18 °C for 3 days at the market shelf condition. Despite chitinase activity peaking on day 14 of cold storage, it peaked significantly on day 7 in Nano-(T)-EO-CS and Sporekill^®-treated tomatoes. The Nano-(T)-EO-CS coating enhanced ferric-reducing antioxidant power and total phenol content in tomatoes for 7 and 14 d of postharvest storage. The chitosan-based edible coating loaded with thyme essential oil offers a sustainable, eco-friendly alternative to chemical fungicides for improving tomato shelf life and reducing decay. Full article

Survivin, a pivotal member of the inhibitor of apoptosis proteins (IAP) family, plays critical roles in cell cycle regulation and division. Survivin is overexpressed in most malignancies, making it an attractive therapeutic target. Due to its high specificity and potency, siRNA-based RNA interference (RNAi) has emerged as a powerful therapeutic strategy for effectively downregulating disease-related genes such as survivin in cancer therapy. However, naked siRNA suffers from rapid enzymatic degradation, poor cellular uptake, and off-target effects, severely limiting its therapeutic efficacy in vivo. Development of polymer-based nanocarriers for tumor-targeted delivery of survivin siRNA (siSurvivin) holds great potential to address these challenges. In this review, we first described the structure and function of survivin and summarized the survivin-targeted therapeutic strategy. Then, the siRNA delivery systems, particularly the polymeric nanocarriers, were introduced. Furthermore, a plethora of polymer-based nanocarriers for tumor-targeted siSurvivin delivery, including synthetic polymers (branched polymers, dendritic polymers, polymeric micelles), natural polymers (polysaccharides, proteins, and others), lipid-polymer hybrid nanoparticles, and polymer composite nanoparticles, were elaborated. Promising results underscore the potential of polymer-based nanocarriers for survivin siRNA delivery to enhance cancer therapy, providing a roadmap for future clinical translation. Full article

Polymers derived from renewable polysaccharides offer promising avenues for the development of high-temperature, environmentally friendly drilling fluids. However, their industrial application remains limited by inadequate thermal stability and poor colloidal compatibility in complex mud systems. In this study, we report the rational design and synthesis of epichlorohydrin-crosslinked carboxymethyl xylan (ECX), developed through a synergistic strategy combining covalent crosslinking with hydrophilic functionalization. When incorporated into water-based drilling fluid base slurries, ECX facilitates the formation of a robust gel suspension. Comprehensive structural analyses (FT-IR, XRD, TGA/DSC) reveal that dual carboxymethylation and ether crosslinking impart a 10 °C increase in glass transition temperature and a 15% boost in crystallinity, forming a rigid–flexible three-dimensional network. ECX-modified drilling fluids demonstrate excellent colloidal stability, as evidenced by an enhancement in zeta potential from −25 mV to −52 mV, which significantly improves dispersion and interparticle electrostatic repulsion. In practical formulation (1.0 wt%), ECX achieves a 620% rise in yield point and a 71.6% reduction in fluid loss at room temperature, maintaining 70% of rheological performance and 57.5% of filtration control following dynamic aging at 150 °C. Tribological tests show friction reduction up to 68.2%, efficiently retained after thermal treatment. SEM analysis further confirms the formation of dense and uniform polymer–clay composite filter cakes, elucidating the mechanism behind its high-temperature resilience and effective sealing performance. Furthermore, ECX demonstrates high biodegradability (BOD₅/COD = 21.3%) and low aquatic toxicity (EC₅₀ = 14 mg/L), aligning with sustainable development goals. This work elucidates the correlation between molecular engineering, gel microstructure, and macroscopic function, underscoring the great potential of eco-friendly polysaccharide-based crosslinked polymers for industrial gel-based fluid design in harsh environments. Full article

Almond skin (AS) from industrial almond peeling is considered an agri-food waste with adequate composition to obtain composite films for food packaging due to its richness in polysaccharides, proteins, and phenolic compounds. Composite films based on amorphous polylactic acid (PLA) or partially acetylated polyvinilalcohol (PVA) were obtained by melt blending and compression moulding, incorporating different ratios of defatted AS powder (0, 5, 10, and 15 wt.%). The filler was better integrated in the polar PVA matrix, where more interactions were detected with the filler compounds, affecting glass transition and crystallization of the polymer. The AS particles provided the films with the characteristic colour of the powder and strong UV light-blocking effect, while improving the oxygen barrier capacity of both polymeric matrices (24% in PLA with 15% AS and 42% in PVA with 10% AS). The water vapour permeability increased in PLA (by 192% at 15% AS), but decreased in PVA films, especially with low AS content (by 19% with 5% particles). The filler also provided the PLA and PVA films with antioxidant properties due to its phenolic richness, improving the oxygen barrier capacity of the materials and delaying the unsaturated oil oxidation. This was reflected in the lower peroxide and conjugated dienes and trienes values of the sunflower oil packaged in single-dose bags of the different materials. The high oxygen barrier capacity of the PVA bags mainly controlled the preservation of the oil, which made the effect of the antioxidant AS powder less noticeable. Full article

This article systematically reviews biopolymer phase change materials (PCMs) for TES applications. The review was conducted based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines using databases from Scopus, Web of Science, and Google Scholar. The biopolymer PCMs are categorized as natural, synthetic, and hybrid (a combination of natural and synthetic). A total of 82 articles were included in the analysis. Several thermal properties, mechanical properties, advancements, and challenges are discussed. This article aims to review biopolymer PCMs and identify research gaps for future development. Natural biopolymer PCMs include lipid, lignin, polysaccharides, proteins, etc. Synthetic biopolymer PCMs include supramolecular, polyethylene glycol, polyurethane, polyrotaxane, polylactic acid, etc. Hybrid biopolymer PCMs combine natural and synthetic polymers with conductive fillers, balancing high latent heat with improved thermal stability and durability, although issues, like leakage and low conductivity, persist. It is found that biopolymers can be used as the core and supporting matrix of PCMs. Several cases and configurations of core, supporting matrix, and fillers in the development of PCM from biopolymers are discussed. This article also demonstrates that several natural, synthetic, and hybrid biopolymer PCMs hold promise for demanding TES applications due to their tunable properties and reliability. Biopolymer PCMs offer a sustainable alternative to petroleum-derived substances by minimizing environmental harm, cutting carbon emissions, and promoting a circular economy. This review also highlights several challenges, such as feedstock selection, purification and encapsulation, system compatibility, and standardization, that future research might address to enable scalable, safe, and cost-effective biopolymer PCM solutions. Full article