Search Results (55)

This study focused on investigating the flammability and thermal degradation behavior of wood fiber-reinforced composites consisting of xanthan gum (XG) and gelatin (GEL). These materials could potentially be used as novel bio-based and biodegradable topsoil covers (TSCs) to support reforestation practices. To improve the thermal properties of these composites, xanthan gum was cross-linked with citric acid (CA) or tannic acid (TA) and eventually coated with casein, while gelatin was cross-linked with tannic acid. Thermogravimetric analysis (TGA) showed that thermal degradation of all the prepared samples started at temperatures of 200 °C for xanthan-based samples and 300 °C for gelatin-based samples, which is well above the typical operating conditions for TSCs in their intended application. Single-flame-source tests demonstrated that the CA cross-linked xanthan-based TSCs coated with casein and all the gelatin-based TSCs had excellent self-extinguishing properties. Additionally, Limiting Oxygen Index (LOI) tests showed that gelatin-based composites had LOI values between 30 and 40 vol% O₂, increasing with a higher gelatin-to-wood fiber ratio. These results demonstrated the potential of cross-linked biopolymers (e.g., xanthan and gelatin) as green flame retardants for the production of wood fiber-filled TSCs for use in forestry. Full article

Background: Endothelial dysfunction triggers atherosclerosis pathogenesis. This study aimed at developing a 3D scaffold model able to reproduce in vitro the human vascular intima and study the endothelial damage induced by oxidative low-density lipoproteins (ox-LDLs) and shear stress. (2) Methods: Three-dimensional sandwich-like scaffolds were fabricated using electrospinning technology, functionalized with type I collagen and laminin, and subsequently coated with methacrylated gelatin hydrogel (GelMa) to achieve the final composite structure. Human umbilical vein endothelial cells (HUVECs) were used as the cell model for testing the suitability of 3D supports for cell culture exposed to ox-LDL both under static and shear stress conditions. Cell viability, ultrastructural morphology, and nitric oxide (NO) levels were analyzed. (3) Results: Electrospun mats and their functionalization were optimized to reproduce the chemical and physical properties of the vascular intima tunica. The 3D supports were suitable for the cell culture. Ox-LDL did not affect the HUVEC behavior in the 3D models under a static environment. Conversely, high shear stress (500 µL/min, HSS) significantly decreased the cell viability, also under the ox-LDL treatment. (4) Conclusions: Endothelial cell cultures on electrospun supports exposed to HSS provide a candidate in vitro model for investigating the endothelial dysfunction in atherosclerosis research. Technical improvements to the experimental setting are necessary for validating and standardizing the suggested 3D model. Full article

Background/Objectives: Drug-coated balloons (DCBs) are emerging as a promising treatment for peripheral artery disease; however, current technologies lack flexibility in customizing drug release profiles and composition, limiting their therapeutic potential. This study aims to develop a Gelatin (Gel) and Sodium Alginate (Alg) bioink loaded with apolipoprotein A-I (apoA-I) for controlled drug delivery by using additive manufacturing technologies. Methods: We developed and printed via rapid freeze prototyping (RFP) a Gel and Alg bioink loaded with different concentrations of apoA-I. Mechanical properties related to compressional and tensile forces have been studied, as well as the structural stability and active release from the 3D structure of apoA-I (cholesterol efflux assays). The biological behavior of HUVEC cells with and without ApoA-I was assessed by proliferation assay, metabolic activity analysis, and fluorescence imaging. Results: The 3D structures presented breakpoint stress values consistent with the mechanical requirements for integration within a DCB, and the ability to effectively promote cholesterol transport in J774 cells. Moreover, in vitro studies on HUVECs revealed that the scaffolds exhibited no cytotoxic effects, leading to increased ATP levels and enhanced metabolic activity over time, confirming the possibility to obtain RFP-printed Alg/Gel scaffolds able to provide a stable structure capable of controlled apoA-I release. Conclusions: These findings support the potential of Alg/Gel+apoA-I scaffolds as biocompatible drug delivery systems for vascular applications. Their ability to maintain structural integrity while enabling controlled biomolecular release positions them as promising candidates for personalized cardiovascular therapy, facilitating the rapid customization of bioprinted therapeutic platforms. Full article

Cisplatin, a widely used chemotherapeutic agent, is limited by its poor bioavailability, rapid systemic clearance, and severe side effects. To overcome these limitations, hydroxyapatite–gelatin composite microspheres were developed to improve drug entrapment efficiency (DEE) and provide sustained drug release. Various formulations were prepared by incorporating chitosan either by mixing once or through a sequential coating strategy. By adjusting the loading procedure, the DEE increased from 58% to 99%. The composite microsphere effectively controlled the total drug release duration, extending it from one month to over 5 months. Moreover, the MTT assay demonstrated that all samples effectively inhibited cell growth, with cell viability reduced to less than 20% after 2 weeks of experimentation. These findings demonstrate that the sequential chitosan coating method offers superior drug entrapment and prolonged release compared to mixing chitosan once, exhibiting its potential as a sustained drug delivery system for cancer treatment. Full article

This study aimed to investigate the effect of dip coating and the composition of the applied coating on the structure and sorption properties of freeze-dried carrot bars. The scope of the work included preparing freeze-dried carrot bars, coating them with coatings of different gelatin concentrations, and then analysing the sorption properties based on sorption isotherms. Additionally, the structure was assessed based on porosity, shrinkage, and microscopic observations. Water activity and dry matter content were also measured. Analysis of the obtained results showed that coating caused a significant increase in water activity and a decrease in the dry matter content of freeze-dried carrot bars. There was also a decrease in porosity and volume compared to the control sample, which was confirmed by microscopic analysis. The study of sorption kinetics showed that the coatings limited the hygroscopicity of the samples, reducing the dynamics of moisture adsorption and accelerating the stabilisation of water content. The best model describing the sorption isotherms was the Peleg model, and the isotherms themselves were classified as type IIb according to the Blahovec and Yanniotis classification. The composition of the coating significantly affects the structure and selected physical properties of the bars. FT-IR analysis did not show any significant changes in the bars’ chemical structure. Full article

Guided bone regeneration (GBR) membrane has proven to be a fundamental tool in the realm of bone defect repair. In this study, we develop a mussel-inspired composite biomaterial through polydopamine-assisted, combining gelatin–WPU matrix with the ion-release behavior of Cu–MSNs for augmented bone regeneration. The optimized composite membrane exhibits enhanced mechanical stability, demonstrating a tensile strength of 11.23 MPa (representing a 2.3-fold increase compared to Bio-Gide^®), coupled with significantly slower degradation kinetics that retained 73.3% structural integrity after 35-day immersion in physiological solution. Copper ions act as angiogenic agents to promote blood vessel growth and as antimicrobial agents to prevent potential infections. The combined effect of these components creates a biomimetic environment that is ideal for cell adhesion, growth, and differentiation. This research significantly contributes to the development of advanced biomaterials that combine regeneration and infection-prevention functions. It provides a versatile and effective solution for treating bone injuries and defects, offering new hope for patients in need. Full article

Multifunctional materials requiring low functional voltages are the main goal of new industrial smart technologies. Polypyrrole (PPy) was chemically synthesized by a simple dip-coating process on glucose–porcine skin gelatin nanofibers, accelerating mass production, here shown on nanofiber scaffolds (NFs) with those consisting of composites. The isometric and isotonic characterizations by electro-chemo-mechanical deformation (ECMD) of NFS-PPy are obtained from cyclic voltammetric and chronoamperometric responses in lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), lithium triflouromethanesulfonate (LiTF) and sodium perchlorate (NaClO₄) in propylene carbonate (PC). The results indicate a prevalent anion-driven actuation of the linear actuator (expansion by oxidation and contraction by reduction). Different stress (4–2 kPa) and strain (0.7–0.4%) gradients are a function of the anion Van der Waals volume. During reversible actuation (expansion/contraction), the material stores/releases energy, obtaining greater specific capacitance, 68 F g⁻¹, in LiTFSI solutions, keeping 82% of this capacity after 2000 cycles. The sensitivity (the slope of the linear sensing equation) is a characteristic of the exchanged anion. The reaction of the PPy-coated nanofiber is multifunctional, developing simultaneous actuation, sensing, and energy storage. The materials were characterized by scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectroscopy, and Fourier transform infrared (FTIR) spectroscopy. Full article

The preservation of fish and seafood represents a significant challenge for the food industry due to these products’ high susceptibility to microbial spoilage. Essential oils (EOs), classified as Generally Recognized as Safe (GRAS), have become a natural alternative to synthetic preservatives due to their antimicrobial and antioxidant properties. This review aims to analyze the specific potential of EOs in extending the shelf life of fish and seafood products, offering a natural and effective preservation solution. It provides a detailed overview of EOs applications and mechanisms, highlighting their role in controlling spoilage microorganisms while maintaining product quality. The main methods of EOs application include immersion, spraying, and pipetting, with antimicrobial effectiveness influenced by factors such as concentration, exposure time, and food characteristics like chemical composition and biofilms. Direct EOs application shows challenges that can be countered by exploring nanoemulsion technology as an effective strategy to enhance EOs stability and controlled release, maximizing their preservation impact. Additionally, coatings made from chitosan, gelatin, Farsi gum, and carrageenan, combined with EOs such as oregano, clove, and thyme have shown efficacy in preserving species like rainbow trout, mackerel, and shrimp. However, the commercial feasibility of using EOs in fish preservation depends on consumer acceptance and regulatory compliance. This review offers valuable insights for the industry and researchers by highlighting the practical applications and commercial challenges of EOs in seafood products, underscoring the importance of consumer acceptance and regulatory adherence for market viability. Full article

Gelatin is a natural hydrocolloid with excellent film-forming properties, high processability, and tremendous potential in the field of edible coatings and food packaging. However, its reinforcing by materials such as cellulose nanocrystals (CNC) is often necessary to improve its mechanical behavior, including shape memory properties. Since the interaction between these polymers is complex and its mechanism still remains unclear, this work aimed to study the effect of low concentrations of CNC (2, 6, and 10 weight%) on the molecular organization, thermomechanical, and shape memory properties in mammalian gelatin-based composite films at low moisture content (~10 weight% dry base). The results showed that the presence of CNCs (with type I and type II crystals) interfered with the formation of the gelatin triple helix, with a decrease from 21.7% crystallinity to 12% in samples with 10% CNC but increasing the overall crystallinity (from 21.7% to 22.6% in samples with 10% CNC), which produced a decrease in the water monolayer in the composites. These changes in crystallinity also impacted significantly their mechanical properties, with higher E’ values (from 1 × 10⁴ to 1.3 × 10⁴ Pa at 20 °C) and improved thermal stability at higher CNC content. Additionally, the evaluation of their shape memory properties indicated that while molecular interactions between the two components occur, CNCs negatively impacted the magnitude and kinetics of the shape recovery of the composites (more particularly at 10 weight% CNC, reducing shape recovery from 90% to 70%) by reducing the netting point associated with the lower crystallinity of the gelatin. We believe that our results contribute in elucidating the interactions of gelatin–CNC composites at various structural levels and highlights that even though CNC acts as a reinforcement material on gelatin matrices, their interaction are complex and do not imply synergism in their properties. Further investigation is, however, needed to understand CNC–gelatin interfacial interactions with the aim of modulating their interactions depending on their desired application. Full article

The aim of this study was to analyze the selected physical properties of vegetable bars coated with a coating based on pork gelatin (8% or 12%) with (25% or 50%) or without vegetable broth. The scope of work included developing the composition of edible coatings; preparing bars and coating freeze-dried vegetable bars; analyzing the water activity, dry matter content, the structure of vegetable bars based on microscopic analysis, and porosity; and then conducting a comparative analysis of the obtained results. The analyses show that the composition of the coating and the coating method influence the structure and selected physical properties of freeze-dried bars. Coating freeze-dried vegetable bars increases their water activity to the range of 0.215–0.389, and reduces their dry matter content to 93–96%. The porosity of the samples decreased (85–91%), but the use of coatings in the form of an edible film was more beneficial than immersing the dried material in a film-forming solution. The addition of vegetable broth to edible films improves the physical properties of the dried fruit and may additionally increase the taste of vegetable bars. Full article

In this work, a gelatin/chia mucilage (GN/CM) composite coating material doped with Lactococcus lactis (LS) was developed for strawberry preservation applications. The results of the scanning electron microscope and Fourier transform infrared spectroscopy stated that the enhanced molecular interaction between the CM and GN matrix strengthened the density and compactness of the GN film. Antifungal results indicated that the addition of LS significantly (p < 0.05) improved the ability of the GN coating to inhibit the growth of Botrytis cinerea (inhibition percentage = 62.0 ± 4.6%). Adding CM significantly (p < 0.05) decreased the water vapour permeability and oxygen permeability of the GN coating by 32.7 ± 4.0% and 15.76 ± 1.89%, respectively. In addition, the incorporated CM also significantly (p < 0.05) improved the LS viability and elongation at break of the film by 13.11 ± 2.05% and 42.58 ± 1.21%, respectively. The GN/CM/LS composite coating material also exhibited an excellent washability. The results of this study indicated that the developed GN/CM/LS coating could be used as a novel active material for strawberry preservation. Full article

Bacterial infections are among the most significant health problems/concerns worldwide. A very critical concern is the rapidly increasing number of antibiotic-resistant bacteria, which requires much more effective countermeasures. As nature’s antibacterial entities, bacteriophages shortly (“phages”) are very important alternatives to antibiotics, having many superior features compared with antibiotics. The development of phage-carrying controlled-release formulations is still challenging due to the need to protect their activities in preparation, storage, and use, as well as the need to create more user-friendly forms by considering their application area/site/conditions. Here, we prepared gelatin hydrogel microbeads by a two-step process. Sodium alginate was included for modification within the initial recipes, and these composite microbeads were further coated with chitosan. Their swelling ratio, average diameters, and Zeta potentials were determined, and degradations in HCl were demonstrated. The target bacteria Escherichia coli (E.coli) and its specific phage (T4) were obtained from bacterial culture collections and propagated. Phages were loaded within the microbeads with a simple method. The phage release characteristics were investigated comparatively and were demonstrated here. High release rates were observed from the gelatin microbeads. It was possible to reduce the phage release rate using sodium alginate in the recipe and chitosan coating. Using these gelatin-based microbeads as phage carrier matrices—especially in lyophilized forms—significantly improved the phage stability even at room temperature. It was concluded that phage release from gelatin hydrogel microbeads could be further controlled by alginate and chitosan modifications and that user-friendly lyophilized phage formulations with a much longer shelf life could be produced. Full article

This study explores the synthesis and characterization of chitosan/gelatine films incorporating nickel ferrite (NiFe₂O₄) and cobalt ferrite (CoFe₂O₄) nanoparticles. The magnetic nanoparticles exhibit superparamagnetic behaviour, making them attractive for various applications, including biomedical uses. The X-ray diffraction analysis confirmed the successful synthesis of NiFe₂O₄ and CoFe₂O₄ nanoparticles, and the scanning electron micrographs illustrated well-dispersed ferrite nanoparticles within the biopolymer network, despite the formation of some aggregates attributed to magnetic interactions. Magnetization loops revealed lower saturation magnetization values for the composites, attributed to the chitosan/gelatine coating and the dielectric studies, indicating increased dielectric losses in the presence of ferrites, particularly pronounced in the case of NiFe₂O₄, suggesting interactions at the interface region between the polymer and ferrite particles. The AC conductivity shows almost linear frequency dependence, associated with proton polarization and conduction processes, more significant at higher temperatures for samples with ferrite particles. Full article

Tympanic membrane (TM) perforations, primarily induced by middle ear infections, the introduction of foreign objects into the ear, and acoustic trauma, lead to hearing abnormalities and ear infections. We describe the design and fabrication of a novel composite patch containing photocrosslinkable gelatin methacryloyl (GelMA) and keratin methacryloyl (KerMA) hydrogels. GelMA-KerMA patches containing conical microneedles in their design were developed using the digital light processing (DLP) 3D printing approach. Following this, the patches were biofunctionalized by applying a coaxial coating with PVA nanoparticles loaded with gentamicin (GEN) and fibroblast growth factor (FGF-2) with the Electrohydrodynamic Atomization (EHDA) method. The developed nanoparticle-coated 3D-printed patches were evaluated in terms of their chemical, morphological, mechanical, swelling, and degradation behavior. In addition, the GEN and FGF-2 release profiles, antimicrobial properties, and biocompatibility of the patches were examined in vitro. The morphological assessment verified the successful fabrication and nanoparticle coating of the 3D-printed GelMA-KerMA patches. The outcomes of antibacterial tests demonstrated that GEN@PVA/GelMA-KerMA patches exhibited substantial antibacterial efficacy against Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. Furthermore, cell culture studies revealed that GelMA-KerMA patches were biocompatible with human adipose-derived mesenchymal stem cells (hADMSC) and supported cell attachment and proliferation without any cytotoxicity. These findings indicated that biofunctional 3D-printed GelMA-KerMA patches have the potential to be a promising therapeutic approach for addressing TM perforations. Full article

Magnetite nanoparticles (MNPs) are highly favored materials for a wide range of applications, from smart composite materials and biosensors to targeted drug delivery. These multifunctional applications typically require the biofunctional coating of MNPs that involves various conjugation techniques to form stable MNP–biomolecule complexes. In this study, a cost-effective method is developed for the chlorostannate modification of MNP surfaces that provides efficient one-step conjugation with biomolecules. The proposed method was validated using MNPs obtained via an optimized co-precipitation technique that included the use of degassed water, argon atmosphere, and the pre-filtering of FeCl₂ and FeCl₃ solutions followed by MNP surface modification using stannous chloride. The resulting chlorostannated nanoparticles were comprehensively characterized, and their efficiency was compared with both carboxylate-modified and unmodified MNPs. The biorecognition performance of MNPs was verified via magnetic immunochromatography. Mouse monoclonal antibodies to folic acid served as model biomolecules conjugated with the MNP to produce nanobioconjugates, while folic acid–gelatin conjugates were immobilized on the test lines of immunochromatography lateral flow test strips. The specific trapping of the obtained nanobioconjugates via antibody–antigen interactions was registered via the highly sensitive magnetic particle quantification technique. The developed chlorostannate modification of MNPs is a versatile, rapid, and convenient tool for creating multifunctional nanobioconjugates with applications that span in vitro diagnostics, magnetic separation, and potential in vivo uses. Full article