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The pervasive presence of nanoplastics (NPs) in the environment has gained increasing attention due to their accumulation in living organisms. These emerging contaminants inevitably interact with extracellular polymeric substances along respiratory or gastrointestinal tracts, and diverse organic coating on the surface of NPs, known as bio- or eco-corona, is formed. Although its impact on altering the NP properties and potential cell internalization has been extensively examined, studies on its role in NP partitioning in the cell membrane are elusive yet. In this work, molecular dynamics is used to investigate the formation of chitosan (CT) corona centered on a polyvinyl chloride (PVC) nanoparticle and the uptake of the resulting complex onto lipid membranes. Coarse-grained models compatible with the newly developed Martini 3.0 force field are implemented for the two polymers employing the atomistic properties as targets in the parameterization. The reliability of the coarse-grained polymer models is demonstrated by reproducing the structural properties of the PVC melt and of solvated CT strands, as well as by determining the conformation adopted by the latter at the NP surface. Results show that the spontaneous binding of CT chains of high and intermediate protonation degrees led to the formation of soft and hard corona that modulates the interaction of PVC core with model membranes. The structural changes of the corona adsorbed at the lipid–water interface enable a subsequent transfer of the NP to the center of the saturated lipid membranes and a complete or partial transition to a snorkel conformation depending on the hydrophilic/hydrophobic balance in the CT–PVC complex. Overall, the computational investigation of the coarse-grained model system provides implications for understanding how the eco-corona development influences the uptake and implicit toxicology of NPs. [ABSTRACT FROM AUTHOR]

Background Aim Methodology Results Conclusions The dental pulp's environment is essential for the regulation of mesenchymal stem cells' homeostasis and thus, it is of great importance to evaluate the materials used in regenerative procedures.To assess in vitro (i) the effect of chitosan nanoparticles, 0.2% chitosan irrigation solution, Dual Rinse®, 17% EDTA, 10% citric acid and 2.5% NaOCl on DSCS viability; (ii) the effect of different concentrations of TGF‐β1 on DCSC proliferation; and (iii) whether treatment with TGF‐β1 following exposure to the different irrigation solutions could compensate for their negative effects.(i) DSCS were treated with three dilutions (1:10, 1:100 and 1:1000) of the six irrigation solutions prepared in DMEM for 10 and 60 min to assess the effect on viability. (ii) The effect of different concentrations (0, 1, 5 and 10 ng/mL) of TGF‐β1 on DCSC proliferation was assessed at 1, 3 and 7 days. (iii) The proliferative effect of TGF‐β1 following 10‐min exposure to 1:10 dilution of each irrigation solution was also tested. We used MTT assay to assess viability and proliferation. We performed statistical analysis using Prism software.(i) The different endodontic irrigation solutions tested showed a significant effect on cell viability (p ≤ .0001). Significant interactions between the endodontic irrigation solutions and their dilutions were also found for all parameters (p ≤ .0001). Chitosan nanoparticles and 0.2% chitosan irrigation solution were the least cytotoxic to DSCS whilst 2.5% NaOCl was the most cytotoxic followed by 17% EDTA. (ii) TGF‐β1 at concentrations of 1 and 5 ng/mL resulted in significantly higher proliferation compared to the control group. (iii) Exposure to 17% EDTA or 2.5% NaOCl for 10 min was sufficient to make DSCS cells refractory to the proliferative effects of TGF‐β1. DSCS groups treated with TGF‐β1 following exposure to chitosan nanoparticles, 0.2% chitosan irrigation solution, Dual Rinse® and 10% CA demonstrated significantly higher proliferation compared to non‐TGF‐β1‐treated groups (p ≤ .0001, p ≤ .0001, p ≤ .0001 and p = .01 respectively).The current study offers data that can be implemented to improve the outcome of regenerative endodontic procedures by using less toxic irrigation solutions and adding TGF‐β1 to the treatment protocol. [ABSTRACT FROM AUTHOR]

In this study, a hydrothermal approach was employed to graft chitosan (Chit)/algae (ALG) with salicylaldehyde (SA), resulting in the synthesis of a biocomposite named salicylaldehyde-based chitosan Schiff base/algae (Chit-SA/ALG). The main objective of this biocomposite was to effectively remove methyl violet (MV), an organic dye, from aqueous solutions. The adsorption performance of Chit-SA/ALG toward MV was investigated in detail, considering the effects of three factors: (A) Chit-SA/ALG dose (ranging from 0.02 to 0.1 g/100 mL), (B) pH (ranging from 4 to 10), and (C) time (ranging from 10 to 120 min). The Box–Behnken design (BBD) was utilized for experimental design and analysis. The experimental results exhibited a good fit with both the pseudo-second-order kinetic model and the Freundlich isotherm, suggesting their suitability for describing the MV adsorption process on Chit-SA/ALG. The maximum adsorption capacity of Chit-SA/ALG, as calculated by the Langmuir model, was found to be 115.6 mg/g. The remarkable adsorption of MV onto Chit-SA/ALG can be primarily attributed to the electrostatic forces between Chit-SA/ALG and MV as well as the involvement of various interactions such as n–π, π–π, and H-bond interactions. This research demonstrates that Chit-SA/ALG exhibits promising potential as a highly efficient adsorbent for the removal of organic dyes from water systems. The novelty of this work comes from introducing a new bio-organic based composite adsorbent of chitosan (Chit) biopolymer and algae (ALG) biomass. Moreover, the functionality and chemical stability of Chit–ALG composite was further developed by grafting process with salicylaldehyde (SA) using hydrothermal process. The incorporation of ALG biomass into polymeric matrix of Chit and grafting process with SA makes Chit a unique hybrid adsorbent toward cationic dye (methyl violet dye). [ABSTRACT FROM AUTHOR]

Chitosan (CS) is a biopolymer that offers a wide range in biomedical applications due to its biocompatibility, biodegradability, low toxicity and antimicrobial activity. Syringaldehyde (1) is a naturally occurring organic compound characterized by its use in multiple fields such as pharmaceuticals, food, cosmetics, textiles and biological applications. Herein, development of chitosan derivative with physicochemical and anticancer properties via Schiff base formation from the reaction of chitosan with sustainable eco-friendly syringaldehyde yielded the (CS-1) derivative. Moreover, in the presence of polyethylene glycol diglycidyl ether (PEGDGE) or sodium tripolyphosphate (TPP) as crosslinkers gave chitosan derivatives (CS-2) and (CS-3NPs) respectively. The chemical structures of the new chitosan derivatives were confirmed using different tools. (CS-3NPs) nanoparticle showed improvement in crystallinity, and (CS-2) derivative revealed the highest thermal stability compared to virgin chitosan. The cytotoxicity activity of chitosan and its derivatives were evaluated against HeLa (human cervical carcinoma) and HEp-2 (Human Larynx carcinoma) cell lines. The highest cytotoxicity activity was exhibited by (CS-3NPs) compared to virgin chitosan against HeLa cell growth inhibition and apoptosis of 90.38 ± 1.46% and 30.3% respectively and IC50 of 108.01 ± 3.94 µg/ml. From the above results, it can be concluded that chitosan nanoparticle (CS-3NPs) has good therapeutic value as a potential antitumor agent against the HeLa cancer cell line. [ABSTRACT FROM AUTHOR]

The adsorption of the two anti-cancer drugs doxorubicin (Dox) and curcumin (Cur) and also the simultaneous loading of both drugs on the surface of the innovative inorganic nanostructure MXene/MOF-5 (Mxn-MOF) were investigated using the molecular dynamics (MD) simulation method. In order to study the loading process in presence of polymer, two chitosan and alginate polymers were adsorbed on the carrier, and then the loading of drugs was investigated. Descriptors such as van der Waals energy (vdW), radial distribution function (RDF), and mean square displacement (MSD) were utilized. The values of interaction energies and RDF for the studied systems show that the adsorption of drug molecules in systems containing polymer is better than in pristine ones. It was found that the type of adsorbed polymer on the Mxn-Mof nanostructure has a noticeable effect on the interaction energy between Cur and Dox drugs with the carrier. The obtained results confirmed that increasing the number of drug molecules affects the loading and adsorption process. The analyses show that in the co-loading system, the most stable complex with an average binding energy of − 662.75 kJ/mol belongs to the Mxn-MOF-Chi-Dox/Cur system. The investigation of the studied systems confirms that in the presence of chitosan polymer, the adsorption of drug molecules is stronger in comparison with alginate polymer. The results obtained from this study provide detailed information about the interaction of polymeric drug compounds and nanocarriers at the atomic level, which can be useful in the design of intelligent drug delivery systems. [ABSTRACT FROM AUTHOR]

There is increased interest in developing new eco-friendly materials with antibacterial and antioxidant properties for various technological applications. This study prepared a new chitosan phenolic derivative with a hydroxyl group via a click reaction between chitosan (Ch) and vanillylidene acetone to form the corresponding vanillylidene acetonyl chitosan Schiff base (Va.Ch.SB). Detailed structural characterization was carried out using FTIR, UV–Vis, and 1H-NMR spectroscopy. The substitution degree calculated as 8.81%, according to 1H-NMR analysis. The obtained results confirm the formulation of imine Schiff base bond between chitosan amino groups react and vanillylidene acetone. Furthermore, the thermo-gravimetric analysis indicates that the decomposition behaviour of both chitosan and its vanillylidene acetonyl chitosan Schiff base derivative is nearly identical, with a slight enhancement of the SB derivative. The Va.Ch.SB exhibited duple antioxidant activity of the Va.Ch.SB. The comparative analysis reveals that the antimicrobial properties exhibited efficacy against two strains of gram-positive bacteria, namely Staphylococcus aureus and Staphylococcus haemolyticus, as three strains of gram-negative bacteria, namely Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumoniae. These findings suggest that the Va.Ch.SB has the capability to apply in different medical and environmental contexts. [ABSTRACT FROM AUTHOR]

Antimicrobial resistance is one of the major health problems associated with patient care. In this context, researchers are interested in developing novel, effective and sustainable therapeutic nanoformulations. It has been observed that chitosan, polyvinyl alcohol, copper oxide and Acalypha indica (AI) extract have proven antimicrobial efficacy either individually or in combination. The presented study was focused on development of chitosan/PVA/CuO-AI nanocomposite for antimicrobial activity. In addition, hemolytic activity of the nanocomposite was also determined. Scanning electron microscopy, Fourier-transform infrared spectroscopy and X-ray crystallography confirmed the preparation of the nanocomposite. In addition, the chitosan/PVA/CuO-AI nanocomposite demonstrated effective antimicrobial activity and it was not hemolytic on human blood samples. Moreover, the cytotoxicity assay performed on Danio rerio gill cell line recorded 85% cells viability and no significant morphological alterations were observed. [ABSTRACT FROM AUTHOR]

With a growing population of about 7.8 billion, humans are generating tons of waste in the form of non-biodegradable plastics on a daily basis that ends up in landfills and oceans. The introduction of packaging has been a blessing to mankind by facilitating the ease of convenience in transportation, delivery and general usage. The downside, however, is that majority of the packaging currently available is harmful to the environment and takes thousands of years to decay. This paper discusses the use of chitosan from shrimp shells and other marine animals' exoskeleton waste in food packaging industries. Chitosan extracted from marine organisms is modulated in the form of packaging material. Compared to conventional packaging, chitosan films are 73.4% biodegradable in soil under laboratory conditions whereas 100% degraded in an open field. Chitosan with metal oxides, essential oils, natural extracts, proteins and other polymers show enhanced tensile strength, water vapor permeability, oxygen and ultraviolet barrier. Chitosan and composite film show antimicrobial activity against gram positive and negative bacteria. Comparative approaches on environmental impacts between conventional plastics and chitosan films are enlightened, thereby highlighting the importance of natural polymers as packaging films that are considered economic based on the addition of additives. [ABSTRACT FROM AUTHOR]

In the current study, poly(vinyl alcohol) (PVA) casted films and electrospun nanofibers blended with chitosan (CS), citronella essential oil (CEO) and/or titanium dioxide nanoparticles (TiO2) have been fabricated. Smooth surfaces of PVA, PVA/CS and PVA/CS/CEO casted films were observed while a rough surface can be seen for the TiO2 containing casted film. Electrospun nanofibers have well-defined fibrous structures with a homogeneous distribution of the additives. PVA/CS/TiO2 nanofibers have the smallest average diameter of 75 nm. The light barrier highly affected by the preparation method. Casted films transparency was affected slightly by film composition where the film containing TiO2 has the lowest value of 2.17, and the highest value was 2.77 for PVA/CS film. Electrospun nanofibers are almost opaque in the UV and visible ranges, and moreover, incorporation of TiO2 and CEO improved the UV light shielding, and thus, they can be used for protection against the light-induced oxidation processes. In general, electrospun nanofibers exhibited lower mechanical properties than those fabricated by solution casting. The highest value of tensile strength and elastic modulus was for PVA/CS/TiO2 while the highest value of elongation at break was recorded for PVA. For the thermal stability and regardless the fabrication technique, the neat PVA had the highest values of T10 and T50 where the maximum char residue was recorded for PVA/CS/TiO2. The varied fabrics' morphological, optical, mechanical and thermal characteristics using different fabrication methods can widen the engineered possibilities to cover a wider range of applications as, for example, food packaging. [ABSTRACT FROM AUTHOR]

This study prepared epoxy resin reinforced porous beads (CERBs) by crosslinking a water-soluble epoxy monomer, 1,4-butanediol diglycidyl ether (BDE), with chitosan (CS) using isophorone diamine (IPD) as a crosslinking agent. CERBs are prepared by a one-step method under atmospheric pressure and used for the adsorption of Congo Red (CR). The Sips isotherm model indicates that the maximum adsorption capacity of CERBs for Congo Red is 2289.2 mg g−1. CERBs have a three-dimensional network structure and strong mechanical properties, and can be reused more than 5 times maintaining a high adsorption capacity. Therefore, this material can be produced on a large scale and has great potential for commercial applications. [ABSTRACT FROM AUTHOR]

AbstractMolecularly imprinted polymers (MIPs) have garnered the interest of researchers in the drug delivery due to their advantages, such as exceptional durability, stability, and selectivity. In this study, a biocompatible MIP drug adsorption and delivery system with high loading capacity and controlled release, was prepared based on chitosan (CS) and graphene quantum dots (GQDs) as the matrix, and the anticancer drug oxaliplatin (OXAL) as the template. Additionally, samples without the drug (non-imprinted polymers, NIPs) were created for comparison. GQDs were produced using the hydrothermal method, and samples underwent characterization through FTIR, XRD, FESEM, and TGA. Various experiments were conducted to determine the optimal pH for drug adsorption, along with kinetic and isotherm studies, selectivity assessments, in vitro drug release and kinetic evaluations. The highest drug binding capacity was observed at pH 6.5. The results indicated the Lagergren-first-order kinetic model (with rate constant of 0.038 min−1) and the Langmuir isotherm (with maximum adsorption capacity of 17.15 mg g−1) exhibited better alignment with the experimental data. The developed MIPs displayed significant selectivity towards OXAL, by an imprinting factor of 2.88, in comparison to two similar drugs (cisplatin and carboplatin). Furthermore, the analysis of the drug release profile showed a burst release for CS-Drug (87% within 3 h) at pH 7.4, where the release from the CS-GQD-Drug did not occur at pH 7.4 and 10; instead, the release was observed at pH 1.2 in a controlled manner (100% within 28 h). Consequently, this specific OXAL adsorption and delivery system holds promise for cancer treatment. [ABSTRACT FROM AUTHOR]

Polymers derived from renewable carbon feedstock are destined to play a pivotal role in the transition to a sustainable circular economy, displacing conventional fossil‐carbon materials. Chitin (CT) and chitosan (CS) are well‐suited to develop multifunctional materials that are mechanically resilient and easy to process. Their abundance of hydroxyl and amine groups facilitates hydrogen bonding and electrostatic interactions, making them suitable for persistent pollutant removal from drinking water. Therefore, porous CS cryogels are fabricated by dissolution in acetic acid, coagulation, and subsequent freeze‐drying. To enhance durability in harsh environments, CT cryogels are obtained through acetylation. Furthermore, Fe3O4 nanoparticles are incorporated to enable removal by external magnetic fields. The rapid removal of per‐ and polyfluoroalkyl substances (PFASs) with capacities reaching 451 mg g−1 offers competitive performance against state‐of‐the‐art materials. The shear‐thinning properties of CS enable rapid additive manufacturing in predetermined free‐standing shapes, useful for accessing sites with complex geometries. Life cycle assessment (LCA) confirms the suitability of chitosan and CT cryogels for low environmental impact water remediation applications. Furthermore, the cryogels can be recycled, closing the material loops back into the economic cycle. Altogether, this work demonstrates the potential of chitosan and CT as competitive alternatives to fossil‐carbon derived systems for sustainable environmental remediation. [ABSTRACT FROM AUTHOR]

Background: The non-toxic self-crosslinked hydrogel films designed from biocompatible materials allow for controlled drug release and have gathered remarkable attention from healthcare professionals as wound dressing materials. Thus, in the current study the chitosan (CS) film is infused with oil-in-water Pickering emulsion (PE) loaded with bioactive compound quercetin (Qu) and stabilized by dialdehyde cellulose nanocrystal-silver nanoparticles (DCNC-AgNPs). The DCNC-AgNPs play a dual role in stabilizing PE and are involved in the self-crosslinking with CS films. Also, this film could combine the advantage of the controlled release and synergistic wound-healing effect of Qu and AgNPs. Results: The DCNC-AgNPs were synthesized using sodium periodate oxidation of CNC. The DCNC-AgNPs were used to stabilize oil-in-water PE loaded with Qu in its oil phase by high speed homogenization. Stable PEs were prepared by 20% v/v oil: water ratio with maximum encapsulation of Qu in the oil phase. The Qu-loaded PE was then added to CS solution (50% v/v) to prepare self-crosslinked films (CS-PE-Qu). After grafting CS films with PE, the surface and cross-sectional SEM images show an inter-penetrated network within the matrix between DCNC and CS due to the formation of a Schiff base bond between the reactive aldehyde groups of DCNC-AgNPs and amino groups of CS. Further, the addition of glycerol influenced the extensibility, swelling ratio, and drug release of the films. The fabricated CS-PE-Qu films were analyzed for their wound healing and tissue regeneration potential using cell scratch assay and full-thickness excisional skin wound model in mice. The as-fabricated CS-PE-Qu films showed great biocompatibility, increased HaCat cell migration, and promoted collagen synthesis in HDFa cells. In addition, the CS-PE-Qu films exhibited non-hemolysis and improved wound closure rate in mice compared to CS, CS-Qu, and CS-blank PE. The H&E staining of the wounded skin tissue indicated the wounded tissue regeneration in CS-PE-Qu films treated mice. Conclusion: Results obtained here confirm the wound healing benefits of CS-PE-Qu films and project them as promising biocompatible material and well suited for full-thickness wound healing in clinical applications. [ABSTRACT FROM AUTHOR]

The healing of damaged skin is a complex and dynamic process, and the multifunctional hydrogel dressings could promote skin tissue healing. This study, therefore, explored the development of a composite multifunctional hydrogel (HDCP) by incorporating the dopamine modified hyaluronic acid (HA-DA) and phenylboronic acid modified chitosan (CS-PBA) crosslinked using boric acid ester bonds. The integration of HA-DA and CS-PBA could be confirmed using the Fourier transform infrared spectrometer and 1H nuclear magnetic resonance analyses. The fabricated HDCP hydrogels exhibited porous structure, elastic solid behavior, shear-thinning, and adhesion properties. Furthermore, the HDCP hydrogels exhibited antibacterial efficacy against Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus). Subsequently, the cytocompatibility of the HDCP hydrogels was verified through CCK-8 assay and fluorescent image analysis following co-cultivation with NIH-3T3 cells. This research presents an innovative multifunctional hydrogel that holds promise as a wound dressing for various applications within the realm of wound healing. [ABSTRACT FROM AUTHOR]

In this work, a novel procedure for immobilization of phosphomolybdic acid (PMA) on Magnetic polycalix[4]resorcinarene grafted to chitosan by EDTA (calix-EDTA-Cs) was reported. The heterogeneous nanocomposite (CoFe2O4@calix-EDTA-Cs@PMA) was applied an acid nanocatalyst for the synthesis of 5-aroyl-NH-1,3-oxazolidine-2-ones through the reaction of α-epoxyketones with sodium cyanate (NaOCN) in polyethylene glycol (PEG) as a green solvent under ultrasonic irradiation conditions. Some features of this work include quick reaction time, high reaction yield, easy separation of the catalyst, thermal stability, and eco-friendly. [ABSTRACT FROM AUTHOR]

In this study, a nanocomposite of zinc oxide (ZnO) nanoparticles and chitosan‐based carbon quantum dots (ZnO/chQDs) in the presence of bovine serum albumin (BSA) as a promising drug carrier candidate was synthesized and characterized. For this purpose, chitosan and citric acid were used for the synthesis of chQDs and donepezil (DNP) was selected as a model drug. The BSA binding properties of DNP were analyzed by FT‐IR and UV‐Vis techniques, electrochemical methods and molecular docking in the absence and presence of ZnO/chQDs. The thermodynamic parameters and binding constants of DNP with BSA were also evaluated by these methods. The changes in the structural properties of BSA in the presence of DNP, ZnO/chQDs and ZnO/chQDs‐DNP were monitored by ATR‐FTIR spectroscopy. Cyclic and differential pulse voltammetric techniques and electrochemical impedance spectroscopy were applied to investigate the interactions, using methylene blue in electrolyte solution as redox probe, and its redox behaviour was observed to explore the interactions. Molecular docking was carried out on the interaction of DNP with BSA in the absence and presence of the synthesized ZnO/chQDs, and the results were compared with those of the experimental observations. The experimental results were confirmed by molecular docking studies. [ABSTRACT FROM AUTHOR]

The present study evaluated the performance of multiwalled carbon nanotube (MWCNT)@MgAl-layered double hydroxide (LDH) nanoparticles loaded on poly-2 aminothiazole (PAT)/chitosan (CS) matrix (CPML) to remove Cd2+ ions from aqueous solution. The removal efficiency of modified CS/PAT with MWCNT@MgAl-LDHs was increased significantly compared to pure CS/PAT. The influence of heavy metal ion concentration, pH, temperature, adsorbent dosage, and contact time on the adsorption was examined. The optimum conditions for the adsorption of Cd2+ ions were 25 0C with the adsorbent dosage of 0.06 g and initial concentration for adsorption of the Cd2+ 100 mg/L at pH = 8. The maximum adsorption capacity was measured to be 1106.19 mg/g. The values of thermodynamic parameters namely Gibbs free energy (ΔG°), entropy change (ΔS°), and enthalpy change (ΔH°) indicated the feasibility, spontaneity and the endothermic nature of the adsorption process, respectively. The pseudo-second-order kinetics and the Langmuir model were selected as the best models for the adsorption process. Also, CPML nanocomposite (NC) was successfully tested for p-nitrophenol (p-NP) reduction in the presence of NaBH4. The reaction was nearly completed in 6 min. The fabricated CPML-NC could be reused for three consecutive cycles. [ABSTRACT FROM AUTHOR]

A chitosan-based Cu2+ fluorescent probe was designed and synthesized independently using the C-2-amino group of chitosan with 1, 8-naphthalimide derivatives. A series of experiments were conducted to characterize the optical properties of the grafted probe. The fluorescence quenching effect was investigated based on the interactions between the probe and common metals. It was found that the proposed probe displayed selective interaction with Cu2+ over other metal ions and anions, reaching equilibrium within 5 min. [ABSTRACT FROM AUTHOR]

Currently, an important group of biomaterials used in the research in the field of tissue engineering is thermosensitive chitosan hydrogels. Their main advantage is the possibility of introducing their precursors (sols) into the implantation site using a minimally invasive method—by injection. In this publication, the results of studies on the new chitosan structures in the form of thermosensitive hydrogels containing graphene oxide as a nanofiller are presented. These systems were prepared from chitosan lactate and chitosan chloride solutions with the use of a salt of pyrimidine nucleotide—uridine 5′-monophosphate disodium salt—as the cross-linking agent. In order to perform the characterization of the developed hydrogels, the sol–gel transition temperature of the colloidal systems was first determined based on rheological measurements. The hydrogels were also analyzed using FTIR spectroscopy and SEM. Biological studies assessed the cytotoxicity (resazurin assay) and genotoxicity (alkaline version of the comet assay) of the nanocomposite chitosan hydrogels against normal human BJ fibroblasts. The conducted research allowed us to conclude that the developed hydrogels containing graphene oxide are an attractive material for potential use as scaffolds for the regeneration of damaged tissues. [ABSTRACT FROM AUTHOR]

Society's interest in natural and clean products in many areas, such as food and cosmetics, has increased considerably. It has led to the development of new techniques in the packaging of products so that the wastes from the preferred products can be recycled. In this context, Pinus brutia bark was preferred within the scope of the study to transform natural wastes into functional components and use them as packaging material. P. brutia bark (PBB) samples were collected from Bursa, Turkey. PBB samples were ultrasonically extracted using various solvents (acetone, butanol, ethanol, ethyl acetate, hexane, methanol, petroleum ether, and water) and a solvent‐acidic hydrolysis system. The phenolic content profile of PBB samples was determined using high‐performance liquid chromatography with diode‐array detection, and total flavonoid content, antioxidant capacity, and total phenolic content were determined. Chitosan‐polyvinyl alcohol (CS‐PVA) films loaded with polysaccharides and containing methanolic extract were developed. The physical, chemical, and mechanical properties of the films were characterized. It is known that the thickness of the films determines the mechanical properties required to maintain the integrity of the packaging during storage and transport. From the results of the study, it was concluded that the elongation at break value was higher in CS‐PVA‐PBB‐M films (111.08% ± 10.46%), Young's modulus (31.74 ± 21.37 N/mm2), and tensile strength (3.01 ± 0.50 N/mm2) values were higher in CS‐PVA films. In this case, it was concluded that adding proanthocyanidin to edible films gives flexibility to the films. [ABSTRACT FROM AUTHOR]

Chitosan takes second place of the most abundant polysaccharides naturally produced by living organisms. Due to its abundance and unique properties, such as its polycationic nature, ability to form strong elastic porous films, and antibacterial potential, it is widely used in the food industry and biomedicine. However, its low solubility in both water and organic solvents makes its application difficult. We have developed an environmentally friendly method for producing water-soluble graft copolymers of chitosan and poly (N-vinylpyrrolidone) with high grafting efficiency and a low yield of by-products. By using AFM, SEM, TGA, DSC, and XRD, it has been demonstrated that the products obtained have changed properties compared to the initial chitosan. They possess a smoother surface and lower thermal stability but are sufficient for practical use. The resulting copolymers have a higher viscosity than the original chitosan, making them a promising thickener and stabilizer for food gels. Moreover, the copolymers exhibit an antibacterial effect, suggesting their potential use as a component in smart food packaging. [ABSTRACT FROM AUTHOR]

The most prevalent type of hemodialysis membrane is polysulfone (PSf). However, due to inadequate biocompatibility, it significantly compromises the safety of dialysis for patients. In this study, we modify the surface of the PSf membrane with 2,4-dihydroxybenzophenone (DBPh) groups to serve as anchoring sites during UV irradiation. Subsequently, a tailored sulfonated dihydroxy propyl chitosan (SDHPCS) is grafted onto the modified PSf membrane to compensate for the deficiencies in hydrophilic additives. The modified PSf membrane exhibits outstanding hydrophilicity and stability, as demonstrated by its characterization and evaluation. This paper focuses on investigating the interaction between platelet membrane formation, protein adsorption, and anticoagulant activity. The results show that the modified PSf membrane exhibits remarkable enhancement in surface hydrophilicity, leading to a significant reduction in protein and platelet adsorption as well as adhesion. [ABSTRACT FROM AUTHOR]

Natural extracts, such as those from the residues of the Olea europaea industry, offer an opportunity for use due to their richness in antioxidant compounds. These compounds can be incorporated into porous polymeric devices with huge potential for tissue engineering such as bone, cardiovascular, osteogenesis, or neural applications using supercritical CO2. For this purpose, polymeric scaffolds of biodegradable poly(lactic-co-glycolic acid) (PLGA) and chitosan, generated in situ by foaming, were employed for the supercritical impregnation of ethanolic olive leaf extract (OLE). The influence of the presence of chitosan on porosity and interconnectivity in the scaffolds, both with and without impregnated extract, was studied. The scaffolds have been characterized by X-ray computed microtomography, scanning electron microscope, measurements of impregnated load, and antioxidant capacity. The expansion factor decreased as the chitosan content rose, which also occurred when OLE was used. Pore diameters varied, reducing from 0.19 mm in pure PLGA to 0.11 mm in the two experiments with the highest chitosan levels. The connectivity was analyzed, showing that in most instances, adding chitosan doubled the average number of connections, increasing it by a factor of 2.5. An experiment was also conducted to investigate the influence of key factors in the impregnation of the extract, such as pressure (10–30 MPa), temperature (308–328 K), and polymer ratio (1:1–9:1 PLGA/chitosan). Increased pressure facilitated increased OLE loading. The scaffolds were evaluated for antioxidant activity and demonstrated substantial oxidation inhibition (up to 82.5% under optimal conditions) and remarkable potential to combat oxidative stress-induced pathologies. [ABSTRACT FROM AUTHOR]

Using KOH-modified wheat straw as the precursor, wheat straw biochar was produced through carbonization at 500 °C. Subsequently, a synthetic material containing nano-zero-valent iron (nZVI) was prepared via liquid phase reduction (nZVI-WSPC). To enhance its properties, chitosan (CTS) was used by crosslinking to form the new adsorbent named CTS@nZVI-WSPC. The impact of CTS on parameters such as mass ratio, initial pH value, and adsorbent dosage on the adsorption efficiency of Cr(VI) in solution was investigated through one-factor experiments. Isotherm adsorption and thermodynamic analysis demonstrated that the adsorption of Cr(VI) by CTS@nZVI-WSPC conforms to the Langmuir model, with a maximum adsorption capacity of 147.93 mg/g, and the adsorption process is endothermic. Kinetic analysis revealed that the adsorption process follows a pseudo-second-order kinetic model. The adsorption mechanism, as elucidated by SEM, FTIR, XPS, and XRD, suggests that the process may involve multiple mechanisms, including pore adsorption, electrostatic adsorption, chemical reduction, and surface chelation. The adsorption capacity of Cr(VI) by CTS@nZVI-WSPC remains high after five cycles. The adsorbent is simple to operate, economical, efficient, and reusable, making it a promising candidate for the treatment of Cr(VI) in water. [ABSTRACT FROM AUTHOR]

Insulin-loaded nanofibers were prepared using chitosan as a natural polymer. The loaded insulin with polyethylene oxide was used for preparing monolayer batch S1. Nanofiber S1 was coated by seven layers of film on both sides to form batch S2 as a sandwich containing Layer A (CS, PEG and PEO) and Layer B (PEG and PEO) using electrospinning apparatus. SEM, TEM and FT-IR techniques were used to confirm the drug loading within the composite nanofibers. The in vitro activity that provided a sustained and controlled release of the drug from the nanofiber batch was studied at different pH values spectrophotometrically using a dialysis method. In batches S1 and S2, the release of insulin from nanofiber proceeds via burst release necessary to produce the desired therapeutic activity, followed by slow step. The rate and the percentage release of insulin in batch S2 are found to be higher at all pH values. [ABSTRACT FROM AUTHOR]

Acid mine drainage (AMD) is an environmental issue linked with mining activities, causing the release of toxic water from mining areas. Polyethersulphone (PES) membranes are explored for AMD treatment, but their limited hydrophilicity hinders their performance. Chitosan enhances hydrophilicity, addressing this issue. However, the effectiveness depends on chitosan's degree of deacetylation (DD), determined during the deacetylation process for chitosan production. This study optimized the chitin deacetylation temperature, alkaline (NaOH) concentration, and reaction time, yielding the highest chitosan degree of deacetylation (DD) for PES/chitosan membrane applications. Prior research has shown that high DD chitosan enhances membrane antifouling and hydrophilicity, increasing contaminant rejection and permeate flux. Evaluation of the best deacetylation conditions in terms of temperature (80, 100, 120 °C), NaOH concentration (20, 40, 60 wt.%), and time (2, 4, 6 h) was performed. The highest chitosan DD obtained was 87.11% at 80 °C, 40 wt. %NaOH at 4 h of chitin deacetylation. The PES/0.75 chitosan membrane (87.11%DD) showed an increase in surface hydrophilicity (63.62° contact angle) as compared to the pristine PES membrane (72.83° contact angle). This was an indicated improvement in membrane performance. Thus, presumably leading to high contaminant rejection and permeate flux in the AMD treatment context, postulate to literature. [ABSTRACT FROM AUTHOR]

The current study aims to co‐encapsulate Shirazi thyme (Zataria multiflora) essential oil (ZEO) and nisin into chitosan nanogel as an antimicrobial and antioxidant agent to enhance the shelf‐life of cheese. Chitosan‐caffeic acid (CS‐CA) nanogel was produced to co‐encapsulate Zataria multiflora essential oil and nisin. This nanogel was characterized by dynamic light scattering (DLS), Fourier Transform Infrared (FTIR) spectroscopic analysis, X‐ray diffraction (XRD) analysis, and scanning electron microscopy (SEM) images. The effect of free (TFZN) and encapsulated ZEO‐nisin in chitosan nanogel (TCZN) on the chemical and microbiological properties of Iranian white cheese was assessed. The particle size, polydispersity index value (PDI), zeta potential, antioxidant activity, and encapsulation efficiency of the optimal chitosan‐ZEO‐nisin nanogel were 421.6 nm, 0.343, 34.0 mV, 71.06%–82.69%, and 41.3 ± 0.5%, 0.79 ± 0.06 mg/mL. respectively. FTIR and XRD approved ZEO and nisin entrapment within chitosan nanogel. The chitosan nanogel showed a highly porous surface with an irregular shape. The bioactive compounds of ZEO and nisin decreased the pH changes in cheese. On the 60th day of storage, the acidity of treated samples was significantly lower than that of control. Although the lowest anisidine index value was observed in samples treated with sodium nitrate (NaNO3) (TS), there was no significant difference between this sample and TCZN. The lowest microbial population was observed in TCZN and TS. After 60 days of ripening, Coliforms were not detected in the culture medium of TCZN and TS. The results can contribute to the development of a natural preservative with the potential for application in the dairy industry. [ABSTRACT FROM AUTHOR]

Background: Nerve guide conduits are a promising strategy for reconstructing peripheral nerve defects. Improving the survival rate of seed cells in nerve conduits is still a challenge and microcarriers are an excellent three-dimensional (3D) culture scaffold. Here, we investigate the effect of the 3D culture of microcarriers on the biological characteristics of adipose mesenchymal stem cells (ADSCs) and to evaluate the efficacy of chitosan nerve conduits filled with microcarriers loaded with ADSCs in repairing nerve defects. Methods: In vitro, we prepared porous chitosan microspheres by a modified emulsion cross-linking method for loading ADSCs and evaluated the growth status and function of ADSCs. In vivo, ADSCs-loaded microcarriers were injected into chitosan nerve conduits to repair a 12 mm sciatic nerve defect in rats. Results: Compared to the conventional two-dimensional (2D) culture, the prepared microcarriers were more conducive to the proliferation, migration, and secretion of trophic factors of ADSCs. In addition, gait analysis, neuro-electrophysiology, and histological evaluation of nerves and muscles showed that the ADSC microcarrier-loaded nerve conduits were more effective in improving nerve regeneration. Conclusions: The ADSCs-loaded chitosan porous microcarrier prepared in this study has a high cell engraftment rate and good potential for peripheral nerve repair. [ABSTRACT FROM AUTHOR]

The current research article has investigated the synthesis and characterization of novel iron nanoparticles (INPs) from neem and betel leaves extract combination using response surface methodology–central composite design and coated with chitosan–curcumin (CCINPs) as a biocompatible and contrast agent for magnetic resonance imaging (MRI). The coating of INPs with chitosan and curcumin (CCINPs) was carried out using a simple, easy, chemical‐free ultrasonication method and characteristics were confirmed by UV–visible (Vis) spectrophotometer (UV–Vis), Fourier‐transform infrared spectroscopy, X‐ray diffraction, scanning electron microscope, atomic force microscopy, and vibrating sample magnetometer. The biocompatibility of the particles was ensured by conducting hemolytic and cell viability assays. The nanoparticle was found to be nonhemolytic (<5%) up to 150 μg/mL for both INPs and CCINPs. The cell viability was stable (peripheral blood mononuclear cells‐PBMCs) till 48 h at 150 μg/mL of INPs and CCINPs. Both the test results produced were found to be biocompatible and additionally, an in vitro MRI study of INPs and CCINPs demonstrated the efficiency of the nanoparticle as a negative contrast agent with enhanced contrast nature in CCINPs. Thus, overall results indicate that the green synthesized chemical‐free novel CCINPs could be a potential candidate for a wide range of applications such as MRI, drug delivery, and in magnetic fluid hyperthermia. [ABSTRACT FROM AUTHOR]

Straw and chitosan are underutilized raw materials, which could make a significant contribution to sustainable development. Herein, a novel chitosan-based hydrogel incorporating rice straw cellulose micro-fibrils (SCMF) was prepared to effectively remove Cu(II). FTIR and SEM showed that straw cellulose-g-poly (acrylic acid)/chitosan-g-poly (acrylic acid) interpenetrating polymer networks were prepared and the hydrogel SCCH had a 3D porous structure after cross-linking with AA. The swelling properties of SCCH were studied and compared in various pH solution. The results indicated that SCCH replayed pH responsibility, which had the largest and smallest swelling capacity at pH9.18 and pH4.00 respectively. The pseudo-second-order kinetic model can be effectively used to evaluate swelling kinetics of hydrogels. The effects of contact time and initial concentration on Cu(II) ion removal were investigated. The equilibrium adsorption capacity (Qe) was 209.2 mg/g and the obtained results indicated that the adsorption kinetics conformed to the pseudo-second-order. Chemical adsorption combined with porous physical adsorption endowed SCCH excellent swelling and adsorption properties. Tensile, compression, bending and twisting test convinced that SCMF played a significant role on the improvement of mechanical strength. This novel 3D porous chitosan-based hydrogel was identified to be a promising sorbent with advantages of excellent sorption and mechanical properties. [ABSTRACT FROM AUTHOR]

Nanoclays (layered silicates) have been applied as effective reinforcements for polymeric matrices. Chitosan has gained much research interest owing to its remarkable physical features and applications. It is an important amino-polysaccharide formed from deacetylated chitin. The processability, properties, and applicability of chitosan have been enhanced in the form of nanoclay nanocomposites/hybrids. The ensuing high-performance chitosan/nanoclay nanocomposites have been observed in high-tech applications of engineering to biomedical fields. This state-of-the-art comprehensive overview debates the potential of chitosan/nanoclay nanocomposites. In this regard, numerous design combinations of the chitosan, modified chitosan, and chitosan blends have been observed with nanoclays (montmorillonite, bentonite, laponite, cloisite, halloysite nanoclay). Chitosan/nanoclay nanocomposites have been investigated for toxic ions/dyes/biological pollutants removal, flame retardancy, packaging, and antimicrobial/biomedical applications. Consequently, chitosan blends with laolinite nanoclay revealed thermal stability of 400–600 °C and around 80% degradation. Modified chitosan blends filled with organo-modified montmorillonite had non-flammability properties according to V-0 rating and a decrease in total peak heat release and heat release rate. Chitosan nanocomposites with montmorillonite or cloisite nanoclay have been tested for Pb2+, Cr6+, Cu 2+, Zn2+, etc. ions and adsorption capacity >100–300 mg/g was observed. Moreover, chitosan/montmorillonite nanocomposites had an adsorption capacity of 80–500 mg/g for methylene blue and rhodamin-6 dyes. For antimicrobial packaging application, chitosan/halloysite depicted antibacterial efficiency of > 80% against E. coli and S. aureus bacterial strains. Enhanced characteristics rely on chitosan-nanoclay interactions, interface formation, synergistic effects, and structure-property relationships. The future of these nanomaterials in the technical field depends on new designs, facile fabrication, and overcoming underlying challenges toward nanoclay nanomaterials. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effects of replacing antibiotics with increasing doses of chitosan (CHI) on nutrient intake and digestibility, corn grain excretion, ruminal fermentation, nitrogen metabolism, and feeding behavior in finishing steers fed forage-free diets. Five ruminally cannulated crossbred steers were assigned to a 5 x 5 Latin square experimental design and given the following diets: C0= basal diet with no additives, ANT= basal diet with inclusion of virginiamycin 30 mg/kg DM, C375= basal diet with inclusion of chitosan 375 mg/kg DM, C750= basal diet with inclusion of chitosan 750 mg/kg DM, and C1500= basal diet with inclusion of chitosan 1500 mg/kg DM. Supplementation with CHI did not affect ruminal pH and ammonia nitrogen (N-NH3) concentration. Chitosan quadratically affected corn grain excretion and molar proportion of ruminal butyrate, with greater values for C750. Animals fed C375 showed greater dry matter intake and neutral detergent fiber intake; and greater digestibility of DM, starch, and NDF. Animals fed C750 and C1500 diets presented greater absorbed N compared to ANT. Animals fed ANT, C750, and C1500 spent more time eating and chewing than animals fed CON. More specifically, the dose of 375 mg/kg DM of diet was very promising for steers fed free-forage diet due to its ability to improve nutrient digestibility, with only slight changes in N metabolism. [ABSTRACT FROM AUTHOR]

Fe–N co-doped carbon catalyst has drawn increasing attention in the field of Fenton-like degradation of organic wastewater due to their unique structure and high activity. In this study, Fe–N co-doped carbon catalyst with high catalytic efficiency was prepared by one-step pyrolysis modified chitosan with iron ion absorption, and their property was characterized by XRD, BET, XPS and FTIR. The results demonstrated that the Fe–N co-doped carbon catalyst (αFe@CTS-T) has abundant porous structure, surface functional groups, and unique Fe–Nx configuration, which exhibited a superior catalytic ability for degradation of RhB in H2O2 system, and the removal efficiency of RhB was as high as 99.5% within 30min. In addition, further mechanistic insights by contrast and quenching experiments verified that high removal efficient of RhB mainly attribute to indirect oxidation of surface-bound radicals, 1O2 in the H2O2 system, and the pathway of radical generation was proposed. [ABSTRACT FROM AUTHOR]

Repaglinide (RPG) has a high rate of absorption from the gastrointestinal system after oral administration due to low log P value. Hence, in this study the inotropic gelation process was used to fabricate mucoadhesive microspheres of RPG using biodegradable polymers such as guar gum, chitosan, and fenugreek seed mucilage. The mucoadhesive microspheres were characterized and tested in vitro followed with oral glucose tolerance test on animals. Scanning electron microscopy images demonstrated that the fabricated microspheres were smooth and spherical with lack of pores. The particle size and polydispersity index (PDI) of microsphere was observed as 300 μm and 0.349, respectively with high positive zeta potential of 38.4 mV. The results of percentage yield and swelling index analysis demonstrated 87.04 % and 90.65 %, respectively for optimized formulation with an in vitro release capability of 95.20 % in 10 h. In addition, the results suggested that the mucoadhesive microspheres successfully entrapped 94.86 ± 4.25 % of the RPG. These results clearly indicated that the optimized formulation of RPG fortified mucoadhesive microspheres reduced the blood glucose level (hyperglycemia due to glucose load 2 g/kg) significantly, compared to marketed RPG formulation (0.25 mg/kg) after 2 h of oral administration. Additionally, RPG incorporated microspheres enable the regulated blood glucose level over a 10 h. Hence, the formulation demonstrated overall improvement in anti-diabetic efficacy. [ABSTRACT FROM AUTHOR]

The objectives of this paper were to investigate the existence of Listeria monocytogenes (L. monocytogenes) in different types of cheese (Mozzarella, Thalaga, and Romy cheeses, 40 samples each) sold in Assiut dairy shops and to evalute antibacterial properties of chitosan and its nanoparticles against isolated strains. L. monocytogenes was isolated in higher percentage from Mozzarella cheese (25%) followed by Thalaga and Romy cheese samples. L. monocytogenes isolates were validated by PCR utilising the 16S rRNA gene. Zeta-sizer and TEM were used to characterise nano-chitosan. The minimum inhibitory concentrations of chitosan and nano-chitosan on L. monocytogenes were detected by MIC test. Nano-chitosan (3.125%) could prevent organism growth in cheese as early as the third week. The findings revealed that 3.125% nano-chitosan had a sufficient effect on L. monocytogenes while also providing good consumer satisfaction; therefore, nano-chitosan should be utilised as a natural food additive in Egyptian dairy products. [ABSTRACT FROM AUTHOR]

Zeolitic imidazolate framework-8 (ZIF-8) is a promising material for drug delivery, but its poor stability limits its wide application. In this work, homogeneous dodecahedral ZIF-8 was prepared by the room-temperature solution stirring method, and to improve the stability of ZIF-8, ZIF-8@mSiO2 and DZIF-8 (ZIF-8 after calcination) @PMO composites with the core-shell structure were obtained using mesoporous silica (mSiO2) and periodic mesoporous organic silica (PMO) coatings. Folic acid-coupled chitosan (CS-FA) was modified on nanoparticles, and curcumin (CUR) was used as a model anti-tumor drug to obtain the drug delivery systems with targeting and pH stimulation response: ZIF-8@mSiO2@CUR@CS-FA and DZIF-8@PMO@CUR@CS-FA, which exhibited good dispersion and high drug loading capability. In addition, we used the MTT assay to assess the cytotoxicity of the drug-carrying systems and selected human cervical cancer cells (Hela) as model cells. The results of the in vitro experiments suggested that the final CUR-loaded drug delivery systems had significantly increased anticancer efficiency compared with the free drug CUR, which improved the therapeutic effect of the hydrophobic CUR on tumors. In conclusion, the pH-responsive nanocarriers provided potential for the targeted delivery of anticancer medication, resulting in a platform for drug-controlled release and cancer therapy. [ABSTRACT FROM AUTHOR]

Due to biofilm formation and the development of antibiotic resistance, alternative approaches are required to counter Pseudomonas aeruginosa infections. Additionally, P. aeruginosa produces several virulence factors that play a crucial role in chronic infections. The current study aimed to synthesize rutin-loaded chitosan nanoparticles (RUT-CS NPs) and investigate their antibacterial potential against pathogenic P. aeruginosa strains. RUT-CS NPs were synthesized through ionic gelation technique and characterized using FTIR, XRD, DLS, Zeta, SEM, and TEM analyses. The characterization of the synthesized NPs revealed an amorphous structure with a diameter ranging from 230 to 280 nm. The motility of P. aeruginosa, including swarming, swimming, and twitching, was notably diminished by RUT-CS NPs. Furthermore, the NPs exhibited a substantial biofilm inhibitory effect on P. aeruginosa. Moreover, RUT-CS NPs decreased bacterial pyocyanin levels and proteolytic activity. Findings from the current research demonstrate the potential of RUT-CS NPs as a promising novel treatment option for managing P. aeruginosa infections. [ABSTRACT FROM AUTHOR]

Summary: The stability, microstructure and antioxidant capacity of the composite coating solution of chitosan (CS) and oleuropein (OLE, 0.08–0.32%, w/v) were estimated by zeta potential, rheological properties, scanning electron microscope and 2,2‐diphenyl‐1‐picrylhydrazyl radical scavenging assays. Effects of the composite coating on refrigerated chicken breasts were evaluated by microbial, chemical and sensory assays. The results revealed that the coating solutions were stable, intact and exhibited good antioxidant activities. When chicken samples were stored at 4 °C for 12 days, the microbial population treated with CS + OLE decreased to 5.43–7.59 log CFU g−1 compared with the control (8.41 log CFU g−1). The increase in pH values, total volatile base nitrogen and thiobarbituric acid reactive substances contents, and drip loss rate of chicken samples had also been deferred. Overall, the results indicated that it was feasible to apply CS with OLE to extend the shelf life of chicken breasts. [ABSTRACT FROM AUTHOR]

Summary: This study aims to explore the potential of high hydrostatic pressure (HHP, 300–500 MPa) and ionic polysaccharides (sodium alginate, SA; chitosan, CH) in improving interfacial stability of sweet potato protein hydrolysate (SPPH) emulsions. HHP markedly improved emulsifying performance of SPPH with SA and CH at different concentrations (0.02% and 0.06%, w/v) and enhanced the apparent viscosities of their emulsions. SPPH‐CH0.02% at 400 MPa showed the highest emulsifying stability index (ESI, 255.96 min) and zeta potential absolute value (54.13 mV), and its emulsion exhibited the highest adsorbed peptide and CH at interface (31.72% and 1.51%, respectively) and oxygen radical absorbance capacity (ORAC) value of interfacial layer (264.56 μg TE mL−1). Additionally, multiple potential antioxidant peptides were obtained from interfacial layer of emulsion stabilised with SPPH‐CH0.02% at 400 MPa through LC‐MS/MS, and the relationship between their structure and emulsion stability was analysed. Therefore, HHP has great application potential in production of SPPH‐CH emulsion with enhanced stability. [ABSTRACT FROM AUTHOR]

Summary: Apigenin (AP) is a natural flavonoid with multiple health benefits that can be used in functional foods. However, the hydrophobicity and poor aqueous solubility of AP have hindered its food application. With ethanol injection and spray drying, encapsulated AP in dried chitosan‐coated liposomes could be promising in delivering AP via foods. By comparing with the unencapsulated AP, this study examined the potential of spray‐dried chitosan‐coated apigenin liposomes (SCAL) in preserving the AP content and antioxidant capacity against food‐related heat, pH, light, oxygen and salt conditions. The moisture sorption isotherms and storage stability of SCAL were also investigated. The results show that the encapsulated AP in SCAL had better stability against pH (pH 2, pH 4, pH 6 and pH 7), light, oxygen and salt stress (0.1, 0.3 and 0.5 M NaCl) than the unencapsulated AP. The limits of relative humidity (RH) for SCAL storage were found to be <50% at 25 °C, <60% at 35 °C and <70% at 45 °C. SCAL could preserve AP over 90 days in room (86.55–95.42%) and chilled (91.54–95.79%) conditions. These findings suggest the potential of spray‐dried chitosan‐coated liposomes in improving the stability of AP, hence SCAL is promising for delivering AP in functional foods. [ABSTRACT FROM AUTHOR]

This study aimed to optimize the formulation of chitosan -caffeic acid nanogel containing Shirazi thyme (Zataria multiflora) essential oil (ZEO) and nisin. The independent variables (the concentration of chitosan nanogel, Shirazi -thyme, and nisin) were optimized based on the highest zeta potential and encapsulation efficiency, besides the lowest particle size and IC50(DPPH) values. The results of The Box -Behnken experimental design and Stepwise -response surface model showed the optimal nanogel formulation was as follows: chitosan concentration= 0.4 g; ZEO= 157.1 ppm and nisin= 10.1 ppm. The particle size, zeta -potential, antioxidant activity, and encapsulation efficiency of the optimal chitosan -ZEO - nisin nanogel were 411.39±18.11 nm, 32.90±1.10 mV, 0.79±0.06 mg.mL - 1, 71.06 - 82.69% respectively. Moreover, the addition of optimized nanogel to the Iranian white cheese formulation showed that the treated cheese samples with ZEO and nisin (free or encapsulated in chitosan nanogel) improved the microbial quality of chess. The antimicrobial activity of the ZEO and nisin encapsulated in chitosan - caffeic acid nanogel was higher than a free form of ZEO -nisin. The Coliforms population of cheeses treated with sodium nitrate and chitosan nanogel containing ZEO -nisin was acceptable during 60 days of storage. During the storage period, the most changes in the color and texture (hardness) of the cheese samples were related to the control sample, and the least change was obtained for samples treated with sodium -nitrate and chitosan nanogel (P < 0.05). Also, the sensory quality of the sample containing ZEO and nisin was acceptable for the sensory evaluator. The sample containing chitosan nanogel received an acceptable sensory score (>3) during 60 days of storage. In general, the potential of the nanogel in increasing the shelf-life of Iranian white cheese was comparable with sodium nitrate. [ABSTRACT FROM AUTHOR]

Magnetic bio-nanocomposite hydrogels are a promising platform for tissue engineering and drug delivery applications. This research presents the synthesis and characterization of novel magnetic bio-nanocomposite hydrogel beads based on magnetic hydroxyapatite nanoparticles and chitosan for potential pH-sensitive drug delivery. The successful synthesis was confirmed through various analysis methods. The prepared bio-nanocomposites hydrogel beads exhibited pH-sensitive swelling behavior. Furthermore, the bio-nanocomposites demonstrated a high loading capacity for doxorubicin (DOX) anticancer drug and a pH-sensitive drug release profile, with approximately 80% release rate at pH 5 and less than 10% release rate at pH 7.4. The Weibull kinetic model was the best-fitting function for DOX release from bio-nanocomposite hydrogels at pH 5. The cytotoxicity of DOX-loaded bio-nanocomposite hydrogels against HeLa cells was evaluated, which showed high cytotoxicity after incubation for 48 h at a concentration of 2.5 mg/mL. These findings suggest that the prepared magnetic bio-nanocomposite hydrogel beads have good potential for implantable pH-sensitive drug delivery in the treatment of cancerous tissue. [ABSTRACT FROM AUTHOR]

Nanocomposite blend films were prepared by a simple casting method. Polyvinyl propylene (PVP) and chitosan (PVP/chitosan) were used as a based material. Different CuO nanoparticles concentrations were added to a specific blend film concentration of PVP/chitosan (80/20). The mechanism of the interaction between the blend and the nanoparticles was studied by different characterization techniques. The structure modification was confirmed by X-ray diffraction pattern due to the addition of the nanoparticles, in addition, the complexation and the miscibility between the nanoparticles and the blended composite was confirmed by UV–Vis spectroscopy and Fourier transform infrared spectroscopy is by the appearance of new peaks in the spectrum. The band gap computation and optical characteristics show that the addition of the nanoparticles decreases the crystallinity of the nanocomposites system. The findings show that the surface morphology checked by scanning electron microscopy shape and swelling rate behavior are affected by the integration of CuO nanoparticles into the polymer blend matrix. From all the results, this work has a great interest in wide bioapplications such as wound healing and food packing. [ABSTRACT FROM AUTHOR]

The transdermal route is an important delivery system for the delivery of both systemic and local effects. The effectiveness of therapy is based on adherence of transdermal dosage form to the skin and physiochemical properties of the drug during therapy. Transdermal Film-Forming Gels when applied to the skin after adherence form a thin film and provide the delivery of drug to the body tissues. Novel 5-Fluorouracil loaded Film-Forming Gels was prepared by utilizing natural polymer (chitosan) with variable concentration of penetration enhancers i.e. oleic acid and tween 80 which further affects the drug release. Prepared Film-Forming Gels were subjected to pH determination, viscosity measurement, homogeneity determination and FTIR analysis. Drying test showed film-forming gel was dried within 15 min after application. Moreover, in-vitro release study confirmed the 83% release over 180 min and the ex-vivo release of FFG9 displayed 81.45% release. This novel system would be an effective dosage form for the delivery of drugs. [ABSTRACT FROM AUTHOR]

Chronic wounds pose a significant challenge to wound care professionals and have substantial cause of socioeconomic implications worldwide. This study focuses on the development of a gel containing encapsulated iodine–chitosan graphene oxide nanopockets (I-CH-GO-NPOs) with a comprehensive evaluation to discern its potential in enhancing the wound healing trajectory for full thickness chronic wounds. The prepared I-CH-GO-NPOs gel showed higher antibacterial property of 0.00513 ± 0.00014 mg/ml against gram-positive Staphylococcus aureus bacteria. Further, in vivo wound healing efficacy of I-CH-GO-NPOs was evaluated in Sprague-Dawley rats which showed a significant increase of 99.89 ± 2.2% in the wound contraction. [ABSTRACT FROM AUTHOR]

Lemon essential oil (LEOs) is used as a bioactive compound with unique health properties as a medicine or dietary supplement. Nevertheless, essential oils are chemical compounds sensitive to light, oxidation, and thermal processes. Therefore, encapsulation technique can be a good way to protect them from degradation and evaporation. In current study, biopolymeric nanocapsules containing lemon essential oils (LEOs) were prepared by the emulsion method. The nanocapsules were characterized by their particle size and Encapsulation efficiency (%) ranged from 339.3 to 553.3 nm and 68.09% to 85.43%, respectively. Long-term storage (30 days) under different temperatures (4 °C, 25 °C, and 40 °C) conditions showed that nanocapsules stored at 4 °C were more stable than samples stored at higher temperatures. DPPH and ABTS free radical scavenging activity were measured to evaluate the values of antioxidant activity of LEOs and nanocapsules. The free LEO and nanocapsules were investigated for its antibacterial activity against common Gram-positive and Gram-negative pathogenic microorganisms (Staphylococcus aureus and Escherichia coli) using disk diffusion followed by the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). Our results indicated that the encapsulated LEOs had a significant antioxidant and antibacterial activities, as compared to the free LEO. The LEOs nanocapsules in CS and Hicap can be suggested as an important natural alternative with suitable stability, antioxidant, and antibacterial properties to overcome the challenges associated with the direct application of these bioactive compounds in food. [ABSTRACT FROM AUTHOR]