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Sodium alginate (AlgNa) is often used to prepare oral drug capsules, offering the advantages of facile carrier formation and pH sensitivity. However, these capsules suffer from high porosity, large pore size, and mechanical and physiological instabilities. Although the performance of AlgNa in oral drug carriers can be enhanced through hybridization with other substances, this results in increased complexity and additional preparation steps. To address this problem, organic–inorganic hybrid capsules are herein prepared via the one‐step incorporation of aminosilanes (3‐aminopropyltriethoxysilane and 3‐(2‐aminoethylamino)propyltrimethoxysilane) into AlgNa and evaluated as delivery vehicles for the sustained release of a model drug, diclofenac sodium. The hybrid capsules show elevated drug encapsulation efficiencies (up to 92.7%) and pH responsiveness and outperform pure alginate capsules, exhibiting contraction and low release rates (<10%) in a simulated stomach environment (pH 1.2) and swelling and sustained release (10 h) in a simulated intestinal environment (pH 7.4). The formation of siloxane bonds between the aminosilane molecules results in stronger and more compact capsule membranes contributing to sustained drug release. Thus, our results demonstrate the potential of the proposed capsules, fabricated using a simple ecofriendly method, as carriers for sustained drug release. [ABSTRACT FROM AUTHOR]

Cationic photosensitizers have higher photodynamic antibacterial activity compared with anionic photosensitizers, and with low toxicity and no drug resistance. However, their poor photostability and low utilization rate limit their practical applications. Herein, a new strategy for the construction of a GSH‐responsive antibacterial nanogel system is developed via the electrostatic interaction between methylene blue (MB) and sulfonated sodium alginate (HSSA) to self‐assemble into nanoparticles followed by sulfhydryl cross‐linking in an aqueous solution. The photobleaching of MB can be inhibited due to the self‐aggregation‐caused quenching (ACQ) effect, but the photodynamic activity can be restored by breaking the disulfide‐crosslinking bonds in the nanogel in response to 10 mM GSH. In vitro antibacterial tests prove that the system has antibacterial activity beyond anionic photosensitizers. Antibacterial studies on plants show that the system has targeted antibacterial activity on infected plants and good wettability, retention, and adhesion to plant leaves. Safety evaluation shows that the system has no obvious toxic effect on plants. Therefore, this study provides a new approach to the discovery of novel photodynamic bactericides. [ABSTRACT FROM AUTHOR]

Hydrogels can form physically or chemically interactions with tissues and are widely used in the design of bioadhesive material. Polydopamine (PDA)/polyacrylamide (PAM)‐based adhesion hydrogels have emerged as one of the hydrogel adhesive materials with great potential for development. However, this type of hydrogel has low mechanical and adhesion properties, which has certain limitations in practical applications. Herein, inspired by the mussel adhesion mechanism, we introduced PDA into PAM/3‐aminophenylboronic acid grafted sodium alginate (SA‐PBA) double network system prepared a series of adhesive hydrogels, PDA was crosslinked by dynamic boronic ester bonds with SA‐PBA. The experimental results established that the hydrogels have favorable adhesive, anti‐fatigue, stretchable, and self‐healing properties. Cytocompatibility assay and in vitro hemolysis assay also indicated that the multifunctional hydrogel has excellent cytocompatibility and hemocompatibility. [ABSTRACT FROM AUTHOR]

This study prepares a series of hollow‐structured CS/SA/POSS composite gel spheres with a diameter of ~2.5 mm by using hydrophilic Janus‐type polyhedral oligomeric silsesquioxane (AS‐POSS) as a crosslinking agent in combination with sodium alginate and chitosan via electrostatic adsorption/free radical polymerization. As the content of POSS increases, the wall thickness of the gel spheres also increases from 20 to 30 μm, leading to a more compact and smooth wall structure in the polymerized CS/SA/POSS composite gel spheres. Additionally, the introduction and polymerization of POSS significantly enhance the stability, drug loading rate, and entrapment rate of the gel spheres, providing them with improved drug release capabilities. For hydrophilic drug doxorubicin, the loading rate and encapsulation rate reach 41.2% and 79.9%, respectively, while for the hydrophobic drug ibuprofen, they are 14.7% and 76.3%. Compared to some previously reported drug‐loaded gel materials, the gels prepared in this study demonstrate relatively higher drug loading performance. Thus, these hollow‐structured CS/SA/POSS composite gel spheres hold promise as innovative drug carriers in the biomedical field. [ABSTRACT FROM AUTHOR]

The poor plasticity of coal results in a large amount of dust during the mining process, thereby posing a significant impact on mine safety and the health of workers. In order to address this issue, a method has been proposed to suppress dust by enhancing the plasticity of coal through injecting a reactive material, which forms a colloid within the coal. The results implicated that the self‐active colloidal dust suppressant, composed of sodium alginate, gluconolactone, calcium disodium EDTA, and sodium dodecyl sulfate, effectively improved the moisture content of coal seams and decreased the brittleness of coal. Scanning electron microscopy and specific surface area test revealed that the dust suppressant not only tightly adheres to the surface of the coal after the reaction, but also penetrates the coal pores and forms a colloid on both the inner and outer surfaces of the coal. The material is rich in carboxyl and hydroxyl groups, which forms hydrogen bonds with the carboxyl and hydroxyl groups present in coal. This interaction enhances the toughness of coal. Simultaneously, it has the ability to adsorb water and function as a moisturizer. The combined synergistic effect of these mechanisms fundamentally reduces dust production during the coal mining process. [ABSTRACT FROM AUTHOR]

A rapid and mild coating strategy was applied on the millimeter scale calcium alginate capsules (Ca‐SA caps) by in situ interfacial polymerization of ethyl cyanoacrylate (ECA). The generated poly(ethyl cyanoacrylate) (PECA) coating was initiated by trace water in the surface of the Ca‐SA caps. The effects of ECA content, reaction time, and type of aromatic solvent on the morphology and control‐release property of the resulting PECA‐coated Ca‐SA caps (Ca‐SA caps@PECA) were investigated. The results demonstrated a white PECA layer successfully coated on the surface of Ca‐SA caps. Notably, the Ca‐SA caps@PECA remained consistently pleasing spherical shape as prepared in methylbenzene and ethylbenzene. When the ECA was 6 mL, the thickness of PECA layer of the Ca‐SA caps@PECA was 43.52 μm. Compared with the Ca‐SA caps, the weight retention ratio of water in the Ca‐SA caps@PECA increased by 254.61%, indicating the effective delay of water diffusion from core of the Ca‐SA caps@PECA. Moreover, the PECA coating improved the stability of the Ca‐SA caps@PECA, which achieved release‐controlling of dye at different pH. This method provides solution for surface modification of fragile hydrogel capsules to effectively control the releasing of liquid core, which is highly valuable in the field of food, cosmetic, and medical delivery. [ABSTRACT FROM AUTHOR]

The P(AM‐co‐AMPS)/SA DN hydrogel was synthesized through aqueous polymerization in this study. It formed a crosslinking network with hydrophobic associations between acrylamide (AM) and lauryl methacrylate (LMA), as well as an ionic bond network involving sodium alginate and Ca2+. To enhance its high‐temperature resistance, 2‐acrylamide‐2‐methylpropane sulfonic acid (AMPS) was incorporated into the hydrogel formulation. The structure of the hydrogel was characterized using Fourier transform infrared spectrometer (FTIR), thermogravimetric analyzer (TGA), and scanning electron microscopy (SEM) techniques. Results demonstrated that the hydrogel exhibited excellent temperature resistance and possessed a porous structure. Mechanical testing revealed a high tensile strength of 110 kPa, elongation at break of 995.31%, along with good fatigue resistance and self‐recovery performance during multiple cyclic stretching. Healing experiments indicated that the healing strength of the hydrogel was influenced by temperature variations. Furthermore, pressure plugging tests were conducted on steel models with crack widths of 0.5 and 1 mm, respectively; it was found that the 0.8%P(AM‐co‐AMPS)/SA DN hydrogel could withstand pressures up to 4.5 MPa at a temperature of 70°C. This novel hydrogel material exhibits remarkable mechanical properties along with certain self‐healing capabilities, making it suitable for leak control applications. [ABSTRACT FROM AUTHOR]

The urgent problem to solve is how to design a kind of green and porous adsorbent that can effectively remove dye pollutants in the field of the sewage treatment. The objectives of this investigation are to incorporate zeolitic imidazolate frameworks‐8 (ZIF‐8) particles in situ onto the surface of multiwalled carbon tubes (MWCNTs) and integrate them into an agarose‐sodium alginate (ASA) double network hydrogel. The resulting composite hydrogel beads, denoted as MWCNTs/ZIF‐8/ASA (MZASA), are synthesized using calcium ion crosslinking. The addition of agarose is employed to create a dual‐crosslinked hydrogel, thereby enhancing the mechanical properties of the ASA hydrogel. By incorporating MWCNTs/ZIF‐8 nanoparticles, the surface area of the MZASA hydrogel is augmented, leading to an enhancement in dye adsorption capacity. In batch sorption mode, the maximum absorbency of the resulting hydrogel beads for methylene blue (MB) is 493.799 mg/g, which was a third greater than that of pure SA beads. Absorption of MB obeys the pseudo‐second‐order kinetic model and Langmuir isotherm model, suggesting monolayer chemisorption adsorption. Analysis of the thermodynamics proves that the entire adsorption process is exothermic and spontaneous. Moreover, the MZASA hydrogel beads show high selectivity for cationic dyes in the mixed dye test. Hence, the synthesized MZASA hydrogel beads serve as a highly effective, innovative, and reusable adsorbent for eliminating cationic dyes from water‐based solutions. [ABSTRACT FROM AUTHOR]

The purpose of this study is to explore how to control the conductivity of gel conveniently and effectively through experiments. First, a kind of acrylamide‐based composite with adhesion and conductivity adjustment was prepared by adding silver ions and silver monomers to the gel in one step. The semi interpenetrating network structure formed by the molecular chain of polyacrylamide and catechol modified sodium alginate in the composite is cross‐connected with silver ions to form a double network structure. This change of network structure not only makes the structure of gel more stable, but also brings extraordinary conductivity. Secondly, different types of conductive ions and organic solutions were added to the gel system. Electrochemical impedance spectroscopy showed that the addition of silver enhanced the conductivity of the material; When NaNO3 is used to replace water molecules in PAM, the ionic conductivity can be increased by 75.3% (from 2.44 × 10−5 to 20.8 × 10−5 mscm−1). When PDA/PAM was soaked in AgNO3, the ionic conductivity increased in the range of 10.4% ~ 674%. It provides a novel strategy for controlling the conductivity of composite materials. [ABSTRACT FROM AUTHOR]

Hydrogels have been widely used for adsorbing heavy metal ions in wastewater treatment. Herein, a calcium alginate/poly‐N‐isopropylacrylamide double‐network hydrogel with photothermal responsiveness was prepared for adsorbing heavy metal ions in aqueous solution. The chemical composition, micromorphology, swelling properties, photothermal responsiveness, adsorption properties, and adsorption mechanism of gel microspheres were studied, respectively. The gel microspheres had an interpenetrating three‐dimensional porous structure, and their high porosity morphology and high specific surface area could ensure the adequate exposure of active adsorption sites. The gel microspheres showed excellent selective adsorption of Cr(III), and the theoretical maximum adsorption capacity of 146.16 mg/g was calculated according to the Langmuir model. Besides, its excellent photothermal conversion ability enhanced the resistance to external interference after the adsorption. Our work has provided an innovative approach to solar water purification while optimizing the preparation process. [ABSTRACT FROM AUTHOR]

In recent years, there has been a significant focus on bioactive dressings suitable for treating chronic and acute wounds. Electrospinning nanofibers are considered advanced dressing options due to their high porosity and permeability to air and water, effective barrier properties against external pathogens, and excellent resemblance to the extracellular matrix for wound healing and skin regeneration. This article reviews the recent advancements in the application of electrospinning nanofibers for bioactive wound healing. The review begins with an overview of the wound healing process and electrospinning methods. It then explores the advantages and disadvantages of different synthetic and natural polymers used in the preparation of electrospinning wound dressings. The natural polymers discussed in this review include collagen, gelatin, silk fibroin, chitosan, hyaluronic acid, and sodium alginate. Additionally, the review delves into commonly used synthetic polymers like polyvinyl alcohol, polyvinyl chloride, polyethylene lactone, polylactide, and polyurethane for wound dressing applications. Furthermore, the review examines the blending of natural and synthetic polymers to create high‐performance wound dressings. It also explores the incorporation of functional additives, such as antimicrobial agents, growth factors, and natural extracts, into electrospinning nanofibers to expedite wound healing and tissue repair. In conclusion, electrospinning is an emerging technology that provides unique opportunities for designing more effective wound dressings and care products. [ABSTRACT FROM AUTHOR]

Based on the solution‐diffusion model of pervaporation (PV) technique, the development of thin‐film composite membranes (TFC) with a highly hydrophilic surface and hydrophobic internal structure is more conducive to the rapid adsorption and desorption of water molecules to overcome the trade‐off effect between flux and separation selectivity. Herein, the polyamide PV membrane was fabricated via interfacial polymerization (IP) with trimesoyl chloride (TMC) and polyethylenimine (PEI) as organic and aqueous phase monomer, respectively, on the hydrolyzed polyacrylonitrile (HPAN) substrate. Subsequently, the hydrophilic modification layer was prepared via sodium alginate (SA) crosslinking with Ca2+ to form the egg‐box network. The results indicated the optimized TFC membrane exhibited high separation factor of 525.1 with desirable permeation flux of 2083.9 g m−2 h−1 for the pervaporation dehydration 85 wt% ethanol/water solution at 70°C. The modification method of hydrophilic surface opens up new avenues for the preparation of PV membrane with high separation performance and low‐cost. [ABSTRACT FROM AUTHOR]

Encapsulation is a popular approach used to incorporate lipophilic bioactive molecules in food matrices. In the present work, soybean oil emulsions with different oil volume fractions (ϕ = 0.17 and ϕ = 0.26) stabilized by whey protein aggregates (WPAg), were mixed with sodium alginate (SA) suspensions and atomized over a calcium gelling bath using an airbrush atomization system to obtain emulsion microgel particles (EMP). Rheological measurements of the mixtures of microgel‐stabilized emulsions and SA suspensions showed a significant increase in viscosity when the oil volume fraction was increased. The analysis of the flow curves showed that viscosity decreased with the increase of shear rate for both systems indicating shear thinning behavior. No difference in the size distribution curves of EMP obtained with different oil fractions was observed. The average D4,3 and span values were 509 ± 56 μm, 1.14 ± 0.08 (ϕ = 0.17), and 527 ± 51 μm, 1.19 ± 0.06 (ϕ = 0.26). The encapsulation efficiency in both cases was acceptable (89 ± 5% for ϕ = 0.17 and 74 ± 8% for ϕ = 0.26), and none of the microparticles showed oil release after 2 months of storage. Results showed that the airbrush atomization system to obtain alginate‐based EMP is simple, low‐cost, and does not require heating, making it appropriate for the effective encapsulation of labile lipophilic compounds in the food industry. [ABSTRACT FROM AUTHOR]

Hydrogels are three‐dimensional polymeric materials with applications in various areas such as biomedicine, tissue engineering, pollutant capture systems, and so forth. However, its application is limited due to the reproducibility of its properties. Factors such as the composition of the constituents, the type of union between the polymer chains, and the crosslinking time play a crucial role in ensuring its reproducibility. In this study, the objective is to prepare a matrix with well‐defined properties that ensure controlled release processes. Treatment of Himantothallus grandifolius with Na2CO3 aqueous solution afforded in 18.9% yield alkaline extract. Hydrogels were prepared by ionic complexation of alginate from H. grandifolius, and polyguluronate enriched alginate from Desmarestia ligulata with chitosan stabilized by immersion in 0.1 M CaCl2 solution; better swelling ratio in water was found for hydrogels with low molecular weight chitosan (MW 125,000 g/mol) than those with medium molecular weight chitosan (MW450,000–500,000 g/mol). Liberation of the model drug metformin hydrochloride from alginates: chitosan complexes (3:1) at pH 1.5 was especially low for hydrogel from H. grandifolius during the first 2 h; 70% of metformin was released at pH 6.5 after 24 h. This polyelectrolyte complex constitutes a good material for potential application in biomedicine considering its cationic and anionic characteristics. [ABSTRACT FROM AUTHOR]

This study aimed to synthesize and characterize hydrogels prepared with alginate (ALG) and ora-pro-nobis mucilage (MOPN) by ionic gelation. The hydrogels were produced from solutions containing 0.5, 0.75, 1.0, and 1.25% (w/v) sodium alginate, 0.25, 0.5, 0.75, 1.0 and 1.25% (w/v) MOPN and 1.5 and 3.0% (w/v) CaCl2. The hydrogels were characterized in terms of mechanical strength, degree of swelling, morphology, chemical groups by Fourier transform infrared spectroscopy (FTIR) and x-ray diffraction (XRD); and their thermal properties were assessed by differential scanning calorimetry (DSC) and thermogravimetric and differential thermal analysis (TG/DTA). The results indicated that MOPN acted with ALG in chain crosslinking, confirming its ability to interact with other polymers to form gels. The control hydrogel, composed of only ALG (1.5%), showed a more crosslinked and less amorphous structure with greater thermal resistance, while the hydrogel composed of ALG (1.25%) and MOPN (0.25%) showed a more amorphous, porous structure with lumps. However, these treatments were statistically equal in terms of mechanical strength and degree of swelling, indicating that ALG and MOPN hydrogels are an economically viable alternative to ALG-only hydrogels, where 0.25% (w/v) of the ALG can be replaced by MOPN without significant changes in its mechanical and swelling properties. [ABSTRACT FROM AUTHOR]

In the present study, a novel polyvinyl alcohol‐sodium alginate hydrogel was prepared using ellagic acid loaded nanospheres in its structure. Ellagic acid was loaded into polymeric nanospheres using a double‐emulsion solvent evaporation technique. Obtained nanospheres were dispersed in a polyvinyl alcohol‐sodium alginate hydrogel, prepared using freeze–thaw method followed by freeze‐drying. Ellagic acid loaded nanospheres and the final hydrogel preparation were characterized using scanning electron microscopy, dynamic light scattering, and Fourier transformation infrared spectroscopy, and investigated for ellagic acid content, and release profile. MTT assays were conducted to measure the viability of cells after treatment with the hydrogel, and wound healing activity was investigated through in vivo studies on open wounds of an animal model. Results showed formation of nanospheres with average diameter of 241.5 nm and prolonged‐release profile of ellagic acid during 48 h. MTT assays showed a significant increase in cell proliferation upon treatment of NIH3T3 cells with the hydrogel. The hydrogel also significantly increased the rate of wound closure through improved epithelialization and production of collagen fibers. It can be concluded that the hydrogel containing ellagic acid‐loaded nanospheres prepared in this study can be designated as a biocompatible dressing to accelerate the wound healing process. [ABSTRACT FROM AUTHOR]

This study disclosed the synthesis and characterization of externally and/or internally crosslinked alginate‐gellan gum composite interpenetrating polymer networks (IPN) and IPN hydrogel microspheres for controlled delivery of gliclazid. The internal cross‐linking of the polymer sol was accomplished via slow release of Ca2+ ions from calcium silicate in presence of gluconic acid d‐lactone. The microspheres had spherical shape with smooth surface morphology. The IPN or composite IPN hydrogel microspheres had drug entrapment efficiency of 70%–76%. Incorporation of gellan gum or gellan gum/calcium silicate in the alginate sol sustained the release of drug in simulated gastrointestinal fluids over 12 h without any sign of particle disintegration. Inclusion of calcium silicate in alginate gels was ineffective in controlling drug release under simulated gastrointestinal milieu. The drug release obeyed anomalous diffusion mechanism after inclusion of gellan gum or gellan gum‐calcium silicate in the alginate gel microspheres. Fourier‐transform infrared (FTIR) spectroscopy and zeta analysis confirmed absence of drug‐polymer chemical interaction. The thermal and x‐ray diffraction analyses suggested that the drug transformed into amorphous state after incorporation into composite hydrogel system. Hence, it may be advantageous to combine internal and external gelation procedures for creating composite IPN or IPN hydrogel microspheres for avoiding burst effect of alginate microspheres and managing desired drug release patterns in vitro. [ABSTRACT FROM AUTHOR]

Conductive hydrogel is a novel material that can be used to prepare flexible wearable strain sensors. It paves the way for future uses in electronic skin, human‐computer interaction, and personalized medical monitoring. However, because the majority of conductive hydrogels use pure water as their medium, they will freeze at low temperatures. It will inevitably lose water at room temperature. We developed a PAM/SA/MXene organic hydrogel (denoted as PSMOH). First, MXene nanosheets were added as conductive filler into the double network polymer hydrogel, which was composed of polyacrylamide (PAM) and sodium alginate (SA), we denoted as PSMH. And then immerse the prepared PSMH in a glycerol solution using a solvent displacement method to obtain PSMOH. Even if at extreme temperatures (−30°C), the prepared PSMOH has a strong antifreezing ability and can retain moisture for 8 days. The sensor also has excellent mechanical properties (tensile strain is 1579%), self‐adhesive property, excellent sensitivity (gauge factor is 49.92), low detection limit (1% strain), and excellent fatigue resistance (800 cycles at 30% strain). As a result, the hydrogel can be assembled into a flexible wearable sensor for real‐time monitoring of human motions and other activities. [ABSTRACT FROM AUTHOR]

Ethinylestradiol (EE) is a potent estrogen widely used to treat diseases such as breast cancer, prostate cancer, and menopausal syndrome. The poor aqueous solubility of EE leads to erratic oral absorption, resulting in suboptimal plasma levels. Developing a formulation to enhance the solubility of EE in the gastrointestinal tract would be beneficial to increase the bioavailability of EE. Thereafter, we prepare diethylenetriamine‐β‐cyclodextrin/ethinylestradiol (DETA‐β‐CD/EE) complex, aiming to increase the solubility of EE in water, and design and prepare core‐shell composite hydrogel capsules with aldocellulose and hydroxyethyl cellulose as the core and sodium alginate as the shell. The stability, swelling, drug release behavior and biocompatibility of the core‐shell hydrogel capsules are carefully investigated. And the results show that the prepared hydrogel capsules have the controlled and sustained release ability of soluble DETA‐β‐CD/EE, can achieve pH‐responding to intestinal fluid, and are non‐toxic to normal human cells. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) have received great attention in the fields ranging from antibacterial materials to sensors. Herein, a novel and green strategy based on electrodeposition of polysaccharides (chitosan, carboxylated chitosan, carboxymethyl cellulose, and sodium alginate) is explored to synthesize AgNPs with adjustable particle sizes and their polysaccharide‐based nanocomposite films. These polysaccharides not only serve as the electrodeposited polysaccharide, but also act as the reducing and stabilizing agents for the synthesis of AgNPs. After the electrodeposition of polysaccharides, homogeneous and smooth deposited films (polysaccharide‐based nanocomposite films) have been generated on the anodic electrodes. Spectral analysis and transmission electron microscopy confirm the existence of AgNPs in the nanocomposite films. The as‐fabricated AgNPs from the electrodeposition of four polysaccharides have different particle sizes ranging from 2.19 to 12.89 nm. The difference in the particle size of AgNPs is related to the different reducibility and stabilizing ability of the polysaccharides. This work provides a facile and controllable new electrodeposition strategy for green synthesis of AgNPs with different sizes and their nanocomposite films, which presents great potential in fabricating AgNPs and their nanocomposites with specific particle sizes and particular properties. [ABSTRACT FROM AUTHOR]

Microbial fuel cells (MFCs) are a potential biotechnology for simultaneous degradation of organic wastewater and power generation. In this paper, a biocompatible composite is constructed around a copper mesh with sodium alginate/agar and activated carbon (CM‐SA/AC) and acts as an efficient anode for MFCs after being microbe immobilized. The power performance of the MFC with CM‐SA/AC anode is investigated. The results show that the addition of activated carbon is conducive to the immobilization of bacteria on CM‐SA/AC anode and fast start‐up of MFCs. The power density reaches 1088.6 mW/m2, which is 2.03 times and 1.75 times that of CM‐SA (without activated carbon) anode and carbon felt anode, respectively. In case of a candied wastewater treatment, the MFC with immobilized CM‐SA/AC anode exhibits a much higher power density (724.5 mW/m2) than that with carbon felt anode (145.0 mW/m2), together with a longer stabilization time and a smaller charge‐transfer resistance. The total removal rate of chemical oxygen demand (COD) reaches 79.4 ± 0.65%. The present study will facilitate the development of inexpensive and biocompatible anodes to facilitate the application of MFCs in wastewater treatment. [ABSTRACT FROM AUTHOR]

This study aimed to produce and characterize biodegradable films of sodium alginate incorporated with macaúba pulp extract (MPE‐0, 10%, 20%, and 30%) and evaluate their effects as active sachets containing olive oil. The films were produced by casting technique and mechanical, barrier, and antioxidant properties were evaluated. The incorporation of MPE modified the mechanical, solubility, color, and barrier properties of alginate films. The polyphenol content of the films increased with the addition of MPE, showing antioxidant activity of 4.2 and 4 mg GAE g−1 for ABTS•+ and DPPH, respectively. The film incorporated with 10% of extract (MP10) presented a decrease of 82% in water vapor permeability and an increase in the tensile strength of 2.3 times compared to the control film (without extract). MP10 was used to store olive oil as this formulation showed superior packaging properties compared to the others tested. At the end of the 16 days of olive oil storage, MP10 was able to maintain the quality parameters of peroxide and acidity within the limits established by current legislation. Therefore, these results indicate the great potential of the incorporation of MPE in the elaboration of sustainable and active materials for packaging olive oil and other fatty foods. [ABSTRACT FROM AUTHOR]

A novel facilitated transport film was prepared by coating polyvinyl alcohol (PVA)/polyethylene glycol (PEG)/aminated sodium lignosulfonate on TiO2/ZnO‐modified low‐density polyethylene (LDPE). Monoethanolamine (MEA), diethanolamine (DEA), ethylenediamine (EDA), diethylenetriamine (DETA), tetramethylpiperidine amine (TEMP), and acrylamide (AM) were selected to modify sodium lignosulfonate (Ls) for enhancing the selectivity and permeability of CO2/O2. The fabricated Ls were characterized by fourier transform infrared (FTIR), thermogravimetric test (TG), and scanning electron microscopy (SEM). The CO2 permeability and CO2/O2 selectivity were improved with the increase in the amount of amine groups. Compared with the addition of Ls modified by alcohol amine, the composite film has higher selectivity to CO2 after the addition of DETA‐Ls or TEMP‐Ls. The selectivity of the 1:3:3EDA/MEA‐Ls‐g‐AM composite film reached 13.7, and CO2 permeability increased by 5.54 times. The storage test also demonstrated that the composite films have better freshness retention ability. As a result, modified LDPE coated by PVA/PEG/aminated Ls has the potential as an active modified atmosphere packaging material. [ABSTRACT FROM AUTHOR]

In this study, ZnO‐doped carbon aerogel is synthesized from cellulose in coconut peat with sodium alginate as a binder via both freeze‐drying and pyrolysis processes. Of those, zinc nitrate is used as not only a crosslinking agent to form gel but also a precursor source to dope ZnO in the carbon aerogel matrix. The effect of precursor ratios on the characterization and energy storage capacity of composite aerogel is investigated. As a result, it is indicated that the formed ZnO‐doped carbon aerogel possesses a highly porous structure which is typical for aerogel structure shown by SEM images, density, and porosity. Besides, via the XRD patterns, the confirmation of the ZnO crystal structure is found within the carbon aerogel lattice. In terms of energy storage, based on the specific capacitance results, the ZCA‐4 sample with a sodium alginate and cellulose weight ratio of 1:20 shows the best energy storage with a specific capacitance of 105 F/g in the voltage range of 0–0.5 V and scan‐rate speed of 0.005 V. Therewithal, the ZCA‐4 also performs high durability, high scanning speed tolerance, and stable storage performance with efficiency reaching more than 99% after 500 consecutive scan cycles. These results demonstrate that the ZnO‐doped carbon aerogel has potential applications as electrode materials in supercapacitors. [ABSTRACT FROM AUTHOR]

Development of multifunctional fluorescent inks is gaining attention owing to the current technological developments in optoelectronics. The present work involves the development of a simple and highly fluorescent carbon quantum dot (CQD)‐based nano‐ink suitable for sensor and bioimaging applications. CQDs were synthesized by a one‐pot hydrothermal method using folic acid (FA) a carbon source. The synthesized CQDs were conjugated with hydroxyapatite (HAP) and sodium aliginate (SA) by covalent and ionic linkages methods. Fourier transform infrared (FT‐IR) spectra confirm the formation of nano‐inks by the ionic interaction between the HAP and SA and conjugation with CQDs through hydrogen bonding. The surface morphology of the CQDs and nano‐inks depicts that the particles exhibit in spherical and needle‐like morphological structures, respectively. The X‐ray diffraction (XRD) pattern confirms that the obtained CQDs and fluorescent nano‐ink are highly crystalline in nature. The SA and HAP provided shear thinning ability and structural stability for the fluorescent nano‐ink. The nano‐ink‐based strips displayed high fluorescence under Ultraviolet irradiation. The fluorescent nano‐ink could be used in bioimaging, flourescent coatings, and anti‐counterfeiting applications. [ABSTRACT FROM AUTHOR]

In tissue engineering technique, a biological scaffold with appropriate composition and structure for promoting growth and differentiation of cells thereby regenerating damaged tissue, is a prime necessity. In this paper, 3D‐printed scaffolds comprising sodium alginate (SA) and chitosan (CH) biopolymers of natural origin are reported. Bioinks with varying ratios of SA and CH were prepared and scaffolds were fabricated by 3D printing. The fabricated scaffolds possess many desired properties that are vital for tissue regeneration purposes. The scaffolds possess open pore microstructures with interconnected pores and desired pore size as revealed by scanning electron microscopic image analysis. The polyelectrolyte complex formation (PEC) between SA and CH as revealed by Fourier‐transform‐infrared spectroscopic analysis is favorable as it offers a better surface for cell attachment and proliferation, and an ideal microenvironment for bone regeneration. Among the scaffolds, SA/CH with 60:40 showed controlled swelling and degradation behavior, with higher tensile strength of 0.387 ± 0.015 MPa. In vitro‐biomineralization showed superior apatite layer deposition ability over the SA/CH: 60/40 scaffold surface. The fabricated SA/CH scaffolds are hydrophilic and biocompatible as evident from the contact angle, protein adsorption, MTT assay, and cell attachment studies. However, SA/CH: 60/40 is shown to have superior biological properties compared with the other SA/CH compositions. Thus, it is concluded that 3Dv printed SA/CH: 60/40 scaffold having some superior properties and bioactivity can be used as a suitable matrix for future bone tissue regeneration applications. [ABSTRACT FROM AUTHOR]

In order to improve the degradability of polylactic acid (PLA) composites and screen PLA degradation microorganisms. Sodium alginate was added into the wheat straw/PLA composites, and both composites (with/without sodium alginate) were buried in natural soil for 100 consecutive days subsequently. Weight loss and characterization of the PLA composites, carbon and nitrogen content in soil and microbial community composition were detected after degradation, with the result that the degradability of the PLA composites was greatly improved after the addition of sodium alginate. The weight loss of PLA composites with sodium alginate was 8.5%, which was 1.81 times that of PLA composites without sodium alginate. Sodium alginate and/or wheat straw in the PLA composites took the lead in the beginning course of the degradation. The added sodium alginate serves the purpose of making it easier to degrade the crystallization zone of the PLA composites. Bionectriaceae in the soil shoots up in the number after degradation, signifying its potential to be part of the microorganism family serving to degrade PLA composites. The results would help reveal the degradation mechanism of PLA composites and provide support for the screening of PLA composites degradation microorganisms. [ABSTRACT FROM AUTHOR]

Direct ethanol fuel cells (DEFCs) offer a high degree of design flexibility, ranging from a single cell to a massive multi‐cell that can be used in various applications, including portable devices, transportation, and stationary applications. Unfortunately, the most significant barrier to the commercialization of DEFCs is getting low‐cost and ethanol permeability, high conductivity performance, and extended durability of polymer electrolyte membranes, as key components that highly influence the overall performance. In this paper, the recent progress in developing the polymer electrolyte membrane for the application of DEFCs has been comprehensively reviewed. Focusing on an updated modification of polymeric materials in the last 5 years, including Nafion‐based membrane, polyvinyl alcohol‐based membrane, polybenzimidazoles‐based membrane, chitosan‐based membrane, and sodium alginate‐based membrane, as well as factors and challenges that affected the performance of polymer electrolyte membranes have been discussed, including the main characterization, catalyst selection, cell design, and work in membrane and cell performance of DEFCs. All discussion addresses the strategy to improve the performance of polymer electrolyte membranes in DEFCs in order to penetrate the commercialization stages. [ABSTRACT FROM AUTHOR]

There is an urgent need to develop edible hydrogels that can be served as a main dish with low‐calorie content and high satiety value, yet are easy to digest. However, the development of such hydrogels remains challenging. In this study, low‐calorie edible hydrogels were prepared from gelatin and sodium alginate (gel/SA hydrogels) through a facile acid soaking‐drying method. These gel/SA hydrogels exhibited excellent mechanical properties with texture characteristics similar to that of Liangpi. The sensitivity of gelatin and acidified sodium alginate to pH resulted in a high swelling ratio of the hydrogels, contributing to weight retention in a simulated stomach environment and rapid degradation in a simulated intestinal environment. These properties indicate that these gel/SA hydrogels have a good prospect of being used as low‐calorie food with high satiety value and are easy to digest. Konjac glucomannan can also be incorporated into the gel/SA hydrogels to further improve their biological functionality. [ABSTRACT FROM AUTHOR]

Self‐rolling allows the bilayer to transform into a 3D structure in response to specific external stimulation, such as heat, humidity, ions, etc. Herein, we report a 4D printing bilayer with a top sodium alginate layer and bottom polycaprolactone layer that could be rolled up to a tubular structure upon exposure to heat and Ca2+ solution stimulation. The discrepancy in the swelling and thermal‐responsiveness between alginate and polycaprolactone induced the self‐rolling under different stimuli. The self‐rolling behavior of the bilayer depends on the aspect ratio, thickness ratio of the bilayer film, the pattern, and external stimuli. Thus, a tailorable surface of the self‐rolled tube was obtained by tuning the bilayer parameter and the stimuli medium to meet varied demands. This controllable shape changing provides a strategy for the preparation of well‐defined tubular structures. Besides, the biocompatibility of bilayer film suggests the potential application in the field of biomedical device such as vascular stent. [ABSTRACT FROM AUTHOR]

Biomaterial scaffolds house and direct cells to grow, exposing them to appropriate growth factors. Most of them are designed to degrade at a controlled rate as the new host tissue replaces them. Here, we show that scaffolds obtained through electrospinning of PVA with 3.5, 4.0, and 5.0 wt% of SA showed a gradual degradation rate under physiological conditions during 100 days of incubation. This behavior is proportional to the SA concentration used, with a mass loss of (41%, 47%, and 49% for each system) after 60 days. Moreover, the dielectric properties (EIS) of the scaffolds correlate with their degradation rate throughout the exposition period (100 days), as indicated by the observed decrease in resistance over time. The 4.0 wt% system showed the lowest capacitance value (1.5 10–5 F) and the highest resistance (4.6106 ohm‐cm2) behavior among all concentrations. Additionally, the morphological analysis through SEM and AFM showed a shrank in the surface morphology after the degradation process and determined the degree of roughness (Ra). Higher roughness prior to the cytocompatibility test promoted increased proliferation and adhesion of HaCat cells, as observed in the 4.0 wt% PVA/SA system (1422 nm Ra). These biomaterials have great potential in wound dressing applications. [ABSTRACT FROM AUTHOR]

At present, the physical properties of hydrocolloids limit their wide application in food industry. To improve the viscoelasticity of sodium carboxymethyl cellulose (CMC) and sodium alginate (SA), cellulose nanocrystals (CNCs) were added into CMC and SA solutions to regulate the non‐Newtonian flow behaviors of composite systems under different conditions. The rheological properties of CMC/CNCs or SA/CNCs composite systems were studied using steady rheological measurements, dynamic rheological measurements, and creep compliance experiments. It was found that the viscosities and elastic modulus of CMC were positively related to CNCs concentrations in acid, neutral or alkaline environments. When the CNCs content was higher than 5% at pH 9.45, the gelation of CMC was accelerated, and the gelation strength was increased. The damping factor of SA decreased with increasing calcium ions contents. When calcium ions content was higher than 0.07%, the damping factor of SA was less than 1, indicating that SA system achieved gel transformation. The effect of CNCs on the apparent viscosity, shear stress, and storage modulus of CMC was more obvious in comparison to that of SA. Overall, as a rheology modifier, CNCs can minimize the contents of food colloids in any functional fluid while maintaining the thickening rheology. [ABSTRACT FROM AUTHOR]

The hydrophilicity is acknowledged critically to raise anti‐fouling of membranes conferring a leaching problem over a prolonged operation. To decrease the leaching of hydrophilic material in modified membranes, poly(vinylidene fluoride) (PVDF) ultrafiltration membranes is herein presented using covalent organic framework (COF)‐poly(acrylic acid) (PAA) modifier via PAA‐catalyzed in‐situ COF synthesis method. The modified PVDF membrane with an optimized COF‐PAA content showed higher water flux (95 L/m2 h), greater bovine serum albumin rejection, and superior antifouling properties to sodium alginate (95% FRR values). The stability test conducted on COF‐PAA‐modified PVDF membrane gave a lower leaching rate of PAA than that of the PAA‐modified counterpart. The membrane containing COF‐PAA compared with the COF‐free counterpart showed a smaller water contact angle down to 55°. The morphologies of the COF‐modified membranes and the COF‐free counterpart studied with scanning electron microscope found that the COF in tight bonding to PAA was homogeneously bonded to the membrane surface. The surface modification contributes to greater stability and anti‐fouling properties of the membrane. The enhanced properties can associate with the reduced pore size of PVDF membrane via in‐situ COF synthesis using the catalyst PAA. This work provides a novel strategy towards the further development of efficient composite membranes with enhanced antifouling properties and water flux. [ABSTRACT FROM AUTHOR]

Hereby, fabrication of hyaluronic acid/gelatin/sodium alginate (HA/Gel/SA) polymeric films, which contain electroconductive poly(3,4ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT:PSS) particles, is studied for drug release applications. The characterization of synthesized PEDOT:PSS and HA/Gel/SA‐(PEDOT:PSS) films is verified by using FT‐IR and RAMAN spectroscopy. Conductivity values of the films containing 0, 4, and 6% v/v PEDOT:PSS are found via a four‐point probe technique to determine the optimum composition of the films for the targeted field. Additionally, swelling, mechanical, and cytotoxicity tests are carried out according to the related methods. Ciprofloxacin (CIP), which is a commonly used antibiotic, is loaded into the polymeric matrix and its release behavior is investigated. All results indicate that the incorporation of PEDOT:PSS increases the mechanical performance and decreases the burst release of drug resulted in more sustained release profile. The HA/Gel/SA‐(PEDOT: PSS) formulation is clearly a promising drug carrier that also supports cell viability due to its high cytocompatibility. [ABSTRACT FROM AUTHOR]

Polypropylene (PP) porous flat membrane is ultrathin and has high porosity, which is suitable for the support of forward osmosis (FO) membrane. However, its high hydrophobicity is its Achilles heel. In this study, dopamine and UiO‐66‐NH2 were co‐deposited onto the surface of PP support, and then interfacial polymerization was performed to fabricate a thin‐film nanocomposite (TFN) FO membrane. The reaction‐generated polydopamine improved the hydrophilicity of PP membrane, and at the same time enhanced the adhering of UiO‐66‐NH2 to the support. The experimental results indicated that the UiO‐66‐NH2 nanoparticles were anchored evenly on the surface of the support, which improved the water flux of FO membrane from 11.1 LMH (TFC, TFN‐0 without UiO‐66‐NH2) to 20.7 LMH (TFN‐0.1, with 0.1 wt% UiO‐66‐NH2) using 1 mol/L NaCl as the draw solution in FO mode. Compared with TFC membrane, TFN‐0.1 membrane also exhibited relative lower specific salt flux (~0.252) and structural parameter (~379 μm). When separating sodium alginate foulant, the normalized water flux recovery ratio of TFN‐0.1 was remained 0.89, and most of the fouling was reversible, as for TFC membrane the data decreased to 0.76 after 2 cycles of operation. These results suggested that UiO‐66‐NH2 modified FO membrane exhibited good permeation and antifouling property. [ABSTRACT FROM AUTHOR]

Drugs with less aqueous solubility and permeability acquire significant hurdles in designing safe and effective formulations. The purpose of this study was to prepare an adenosine (ADS): β‐cyclodextrin (β‐CD) inclusion complex that could be consistently incorporated into a nanocomposite system for topical administration. Several procedures, including kneading, microwave irradiation, and co‐precipitation, were used to develop an adenosine: β‐CD inclusion complex. ROESY, DSC, XRD, and 1H NMR spectroscopy were used to analyze the adenosine‐β‐CD inclusion complex. Then bentonite (BN) incorporated chitosan (CH) and sodium alginate (ALG) nanocomposite were synthesized by microwave irradiation method. Response Surface Methodology (RSM) design was executed to optimize the reaction parameters. The Minimum Resolution V design was implemented to find significant variables to get maximum percentage swelling. The inclusion complexes of ADS: β‐CD were directly loaded into the CH/ALG/BN nanocomposite and the adenosine release was analyzed in simulated intestinal fluids (SIF) and simulated gastric fluids (SGF). Five kinetic models were investigated to know about the drug release mechanism. After a 24‐h interval, the ADS final release was 86 ppm at pH 2, 96 ppm at pH 7, and 85 ppm at pH 7.4. Bentonite has a layered structure that allows it to introduce the drug molecule into its cavity, resulting in sustainable adenosine release. The exploratory kinetic analysis demonstrated that β‐CD influences polymer relaxation, resulting in slow release. [ABSTRACT FROM AUTHOR]

The present study aims at developing and characterizing gum odina ‐ sodium alginate based microsphere as a carrier for capecitabine. Microspheres with varying concentration of polymers (gum odina and sodium alginate) were formulated using calcium chloride as a cross‐linker by ionotropic gelation technique. The formulated microspheres were optimized by entrapment efficiency, drug yield, particle size, swelling index, and in vitro drug release study. The optimized microsphere (F6) was characterized in terms of SEM, AFM, FTIR, XRD, degradation study, moisture content study, and antioxidant activity. The F6 was spherical in shape with a mean diameter of 568.33 ± 45.76 μm and drug entrapment efficiency of 45.91 ± 2.94%. In vitro dissolution study of optimized formulation exhibited negligible released in 0.1 N HCl (pH 1.2) and followed by 100% release in phosphate buffer (pH 7.4) within 24 h. In vitro cytotoxicity assay (MTT) of formulation F6 on HT29 human colon cancer cell line indicated inhibition of the proliferation of tumor cell over a longer period of time. The overall experiment indicated that capecitabine loaded natural polymers based formulated microsphere could be a promising approach for the prevention of colon cancer. [ABSTRACT FROM AUTHOR]

In this paper, from different aspects of internal material composition, biomass modification method and assembly process factor of the biomimetic gelatinous polymer actuator (BGPA), its three process approaches including ionic liquid (IL, [EMIm]BF4) doping amount, sodium alginate (SA) ‐ carboxymethyl chitosan (CMCS) crosslinking ratio and casting assembly temperature were comprehensively compared, and accordingly their technology efficiency and promotion mechanism on response output performance of the BGPA had also been fully researched. The results suggested that under monotonic work cycle, when the IL doping amount was 4 ml, operating life of BGPA reached the maximum of 1720 s and its smallest tremor amplitude was 8.51%. When the SA‐CMCS crosslinking ratio was 5:5, all three evaluation indexes of the duty cycle, internal resistance and elastic modulus of BGPA achieved the minima around 0.97%, 1.61 Ω and 0.207 MPa, respectively. When the casting assembly temperature was 50°C, specific capacitance and output force density of the BGPA separately obtained the largest values of 551.34 mF/g and 16.249 mN/g. Within the cycle repetition period, the best stable output force of the BGPA was approximately 2.877 mN with 4 ml ionic liquid, and its optimal electron current was 12.771 mA at 50°C. [ABSTRACT FROM AUTHOR]

Curcumin is a promising natural drug in cancer therapy. However, its therapeutic applicability is limited by its low solubility, short half‐life, and low bioavailability. In this work curcumin is encapsulated in stimuli‐responsive magneto‐polymeric nanoplatforms aiming at improving its bioavailability and efficiency for delivery in biological media. MnFe2O4 magnetic nanoparticles (MNPs) were synthesized via thermal decomposition, coated with sodium citrate and then functionalized with multilayers of chitosan and sodium alginate, by means of the layer‐by‐layer deposition technique. A mesoporous polymeric‐magnetic nanoplatform was produced capable of a controlled and sustained release of curcumin under temperature, pH and alternating magnetic field (magnetic hyperthermia) stimuli. As the temperature and pH of the medium increased, an increase in the rate of curcumin release was observed in a two‐stage process, following the Gallagher‐Corrigan mathematical model. The use of magnetic hyperthermia resulted in a faster diffusion‐based release of curcumin. Increasing the number of polymer layers assembled on top of MNPs hinders the release of the curcumin molecules from innermost regions of the multilayers. These results show that magnetic hyperthermia provides a means for the controlled heat‐induced release of curcumin, which can lead to an enhanced therapeutic action for curcumin. [ABSTRACT FROM AUTHOR]

"Mechanical properties" are crucial for biodegradable and/or non‐biodegradable materials used in tissue engineering applications. In this study, bio‐hybrid films were produced by using both Bifidobacterium animalis subsp. lactis BB‐12 probiotic strain and Bifidobacterium infantis in combination with sodium alginate (SA), which demonstrates biocompatibility and facilitated gelation properties. Bio‐hybrid films were characterized by using different methods. Based on the spectroscopic and mechanical analysis, it was found that mechanical strength increased in films produced by adding Bifidobacterium infantis in SA while this increase was relatively lower as compared to those containing Bifidobacterium animalis subsp. lactis BB‐12 as cross‐linking ratio increases. Besides, bacteria contained in bio‐hybrid films increased the percentage of amorphous zone of SA in SA/bacteria films, which reduced the crystallinity ratio. This indicated that crystalline chains contained in the structure of SA are degraded by bacteria. [ABSTRACT FROM AUTHOR]

This work presents a prepare method of a bio‐foam constituted by sodium alginate, chitosan (CH), and glyphosate to form a material to be applied in controlled release of herbicide. It was investigated the influence of mixture pH on the bio‐foam physicochemical properties. Kinetic studies of glyphosate adsorption and release were performed. The interactions between the polysaccharides and the herbicide were also investigated. The bio‐foams were evaluated for their mechanical and morphological properties. All samples presented swelling degree above 1000%. The bio‐foam prepared at pH 6 presented a higher compression resistance and provided the higher herbicide adsorption. The bio‐foam was able to control the release of glyphosate. The release kinetics reached equilibrium state after 30 days, during which cumulative release was approximately 90%. Confocal microscopy images showed the preferential interaction of glyphosate with the CH molecules in bio‐foam. This work presents a new perspective for polysaccharide systems, enabling new high‐performance agricultural applications. [ABSTRACT FROM AUTHOR]

In this work, hydrogels composed of cellulose nanofibril (CNF) and sodium alginate (SA) were prepared as a pH‐responsive release system by controlling the amount of CNF and SA. Scanning electron microscopy, thermogravimetric analysis, and swelling rate methods were used to characterize. The results showed that when the mass ratio of CNF to SA was 2:1, CNF/SA hydrogels with better morphology were obtained. Due to the deprotonation or protonation of calcium alginate, as the pH changing from 1.5 to 11.0, the swelling ratio increased from 7 times to 19 times compared with its dry weight. The drug release behaviors of the CNF/SA hydrogels using ibuprofen (IBU) as a model drug were investigated in vitro. The release of IBU was faster in alkaline conditions and slower in acidic conditions. The drug release mechanism under pH stimulation could be interpreted by the Fickian diffusion and erosion effect based on Korsmeyer‐Peppas model. [ABSTRACT FROM AUTHOR]

Conductive hydrogels with high flexibility, superior formability, good mechanical elasticity, and excellent biocompatibility have emerged as promising materials for broad applications in flexible/wearable electronic devices. In this work, a conductive dual‐network PVA/SA/MXene hydrogel (PSM‐h) composed of polyvinyl alcohol, sodium alginate, and MXene (Ti3C2Tx) is constructed by a green method without using chemical crosslinking agents. The resultant hydrogel with dual‐network feature shows excellent cytocompatibility (no toxicity for human umbilical cord mesenchymal stem cells), high stretchability (up to 263%), and superior anti‐fatigue ability (stretched up to 1000 cycles). More importantly, PSM‐h based strain sensor presents good sensing sensitivity with a fast response time (62.5 ms) and a low detection limit even under a very slight strain of 0.2%. In terms of the practical application, the PSM‐h based strain sensor can be applied to detect and distinguish various human motions. [ABSTRACT FROM AUTHOR]

Hydrogels can be one of the best polymeric wound dressings due to the desirable properties of wound healing. In this study, emphasizing the use of natural biomaterials such as Aloe vera and honey in the structure of cross‐linked polymers, a novel hydrogel was produced that might be applied to healing wounds. In the beginning, four hydrogel groups were made from a combination of Sodium Alginate and Chitosan with Aloe vera extract and honey in optimum concentrations. Then the structure of those was evaluated by SEM and FTIR. After confirming hydrogels' structural properties, their physical properties, including swelling, porosity, density, mass loss, stability, and WVTR, were examined. Besides, the hydrogel biocompatibility was assessed by analyzing the cell viability and hemolytic activity. Adhesion of the cells to the hydrogel was also observed by SEM imaging. The results showed that the designed hydrogel has a porous structure with interconnected cavities, which their size can provide suitable conditions for cell adhesion, migration, and proliferation. Also, their physical and structural properties can be a strong suit to wound healing. Although honey's application can weaken the hydrogel structure, honey has beneficial properties due to its complex biomolecules. In contrast, Aloe vera in hydrogel generally improved the hydrogel's specificity for wound healing. According to the results of this study, taking advantage of hydrogels containing honey and Aloe vera based on alginate and chitosan polymers led to the formation of an acceptable structure and biocompatibility that can be used in future researches to repair tissues, especially wounds. [ABSTRACT FROM AUTHOR]

In this study, biomimetic sodium alginate (SA)/silk fibroin (SF) scaffolds were successfully fabricated by supercritical CO2 technology. The SA/SF scaffolds exhibited an interconnected porous and extracellular matrix (ECM)‐like nanofibrous structures. Moreover, the SA microparticles were embedded in the SF scaffolds. Increasing the content of SA microparticles could improve tensile strength and compressive strength of the SF scaffolds and reduce the porosity of the SF scaffolds. The addition of the SA microparticles could also regulate the degradation rate of the SA/SF scaffolds. Furthermore, the results of in vitro biocompatibility evaluation, indicated that the SA/SF scaffolds exhibited no obvious cytotoxicity and higher cell adhesion ability and were more favorable for L929 fibroblasts proliferation than pure SF scaffolds. Therefore, the SA/SF scaffolds with ECM‐like nanofibrous and interconnected porous structure have potential application in skin tissue engineering. [ABSTRACT FROM AUTHOR]

Hydrogels containing a large amount of water have been widely studied as fireproof materials. However, the organic networks that composed the gel easily burns as water evaporates. In this work, the widely used intumescent flame‐retardant ammonium polyphosphate was modified by carbon–carbon double bonds (abbreviated as MAPP) and introduced in alginate/poly (acrylamide‐co‐stearyl methacrylate) [alginate/P(AAm‐co‐SMA)] hydrogel by free radical polymerization. The resultant MAPP@alginate/P(AAm‐co‐SMA) hydrogels show good mechanical strength of 650 kPa and healing efficiency of 80%. Thermal analysis and thermal protective performance tests indicate that the MAPP particles improve the thermal stability and heat resistance of gel. The fireproof test shows that the MAPP@alginate/P(AAm‐co‐SMA) gel composite shows twice of fire proof time over the pure hydrogels. [ABSTRACT FROM AUTHOR]

Innovative composites of biopolymers and nanomaterials have been exploited to fabricate wound dressings which show functional abilities to improve different stages of wound healing by a variety of mechanisms. In this study, a polymeric nanocomposite dressing is fabricated by electrospinning of a blend of sodium alginate (SA), poly vinyl alcohol (PVA) and graphene nanoplatelets (Gnp). The crosslinking of the nanofibers is done by thermal treatment followed by ionic bonding of the fibers. The crosslinked fibers are loaded by curcumin, a natural potent anti‐inflammatory compound, encapsulated in monomethoxy poly ethylene glycol‐oleate micelles/polymersomes (NCur). Results indicate that by incorporation of Gnp and NCur into the SA/PVA scaffold the tensile strength is not changed (~7 MPa) but the elongation to break and toughness of the scaffolds significantly increase from 11.25±2.6 and 50.56 to 35.5±5.1% and 125.9 Jm‐3, respectively. The scaffolds support the controlled release of curcumin for 24 h in vitro. Biocompatibility of the scaffolds has been confirmed by cell viability assay on mouse fibroblast cells. Overall, the findings demonstrate the potential applications of the spun fibers for wound dressing purposes. [ABSTRACT FROM AUTHOR]

In this study, the removal of methylene blue (MB) cationic dye from an aqueous solution was investigated using the polymer‐enhanced ultrafiltration (PEUF) technique with sodium alginate (SA) as an extracting soluble polymer, in combination with an ultrafiltration membrane of regenerated cellulose with a 10 kDa molar mass cut‐off. SA was characterized via Fourier‐transform infrared spectroscopy and thermogravimetric analysis. For ultrafiltration studies, the washing method was used to evaluate various experimental variables, such as the pH, SA dose and initial MB concentration, and adsorption isotherms to identify the optimal adsorption conditions. Finally, the regeneration of the SA polymer was evaluated in five consecutive cycles of adsorption–desorption of MB. In the obtained characterization results, the structural composition of SA and the characteristic thermal stability of the polymer were verified. The PEUF results demonstrated that a retention capacity of 98% of the MB was realized at pH 8.0 using 0.025 g of SA at an initial optimal MB concentration of 50 mg L−1. It is possible to observe that the Freundlich model better explain the interaction between the dye and the polymer surface. According to the results is demonstrated the regeneration capacity of the polymer and its subsequent reuse. [ABSTRACT FROM AUTHOR]

Propolis is a complex mixture of phytochemicals, with antibacterial, anti‐inflammatory, and healing properties. All‐trans retinoic acid is implicated in wound healing by stimulating angiogenesis, cell recruitment, extracellular matrix deposition, and reepithelization. The incorporation of both agents to a polymeric wound dressing composed of poly (vinyl alcohol) and sodium alginate may result in improved healing allied to controlled release, fluid uptake, and wound protection. In the present work, we have physically characterized this wound dressing and analyzed its release kinetics. The anti‐inflammatory capacity was assayed. SEM images showed a highly porous structure with a diverse morphology. FTIR spectra displayed a highly cross‐linked structure with both polymers connected by hydrogen bonds and acetal bridges. The wound dressings were able to retain great volumes of PBS. Propolis and vitamin A releasing behavior were maintained for 6 h. The concentrations of the biologically active substances were capable of promoting anti‐inflammatory action in an erythrocyte membrane stabilization model. The wound dressings obtained here showed adequate physical properties. The fabrication process did not affect the anti‐inflammatory capacity. Further tests are needed to ensure the biocompatibility and to assess other biological activities of the therapeutic agents. [ABSTRACT FROM AUTHOR]

Polysaccharides have been widely used for the development of drug delivery systems. These systems can be physicochemically modified to enhance their stabilities and control their drug release profiles. However, such modifications cannot alter their biocompatibility or toxicity. Herein, four structurally modified sodium alginate/carboxymethylcellulose blends are synthesized and loaded with prednisone, and the effects of the modifications on their hydrolytic degradation rates, biocompatibilities, toxicities, and drug release profiles are investigated. All the blends are ionically cross‐linked with Ca2+ and Fe3+. Blend 1 is not modified further, blend 2 is additionally reinforced with 8% w/w of cellulose nanocrystals, blend 3 is treated with epoxidized linseed oil to develop a hydrophobic layer, and blend 4 is chemically cross‐linked with epichlorohydrin. Blends 2 and 4 exhibit similar physicochemical characteristics, appropriate hydrolytic degradation rates and drug release patterns, as well as biocompatibility and non‐toxicity. In‐vitro studies using the osteoblasts and CAM assay demonstrate that blends 2 and 4 are also biocompatible and non‐toxic. In contrast, blend 1 exhibits the highest drug release rate, followed by blend 3. [ABSTRACT FROM AUTHOR]