Search Results (462)

Polyethylenimine (PEI) is a cationic polymer with a high density of amine groups suitable for strong electrostatic interactions with biological molecules to preserve their bioactivities during encapsulation and after delivery for biomedical applications. This review provides a comprehensive overview of PEI as a drug and gene carrier, describing its polymerization methods in both linear and branched forms while highlighting the processing methods to manufacture PEIs into drug carriers, such as nanoparticles, coatings, nanofibers, hydrogels, and films. These various PEI carriers enable applications in non-viral gene and small molecule drug deliveries. The structure–property relationships of PEI carriers are discussed with emphasis on how molecular weights, branching degrees, and surface modifications of PEI carriers impact biocompatibility, transfection efficiency, and cellular interactions. While PEI offers remarkable potential for drug and gene delivery, its clinical translation remains limited by challenges, including cytotoxicity, non-degradability, and serum instability. Our aim is to provide an understanding of PEI and the structure–property relationships of its carrier forms to inform future research directions that may enable safe and effective clinical use of PEI carriers for drug and gene delivery. Full article

In recent years, active packaging has become a focal point of research and development in the food industry, driven by increasing consumer demand for safe, high-quality, and sustainable food products. In this work, solvent casting processed an active antibacterial multicomponent film based on hydroxypropyl methylcellulose incorporated with ferulic acid and chitin nanofibers. The influences of ferulic acid and different content of chitin nanofibers on the structure, thermal, mechanical, and water vapor stability and antioxidant and antibacterial efficiency of films were studied. It was shown that the inclusion of only ferulic acid did not significantly influence the mechanical, water vapor, and thermal stability of films. In addition, films containing only ferulic acid did not display antibacterial activity. The optimal concentration of chitin nanofibers in hydroxypropyl methylcellulose–ferulic acid films was 5 wt%, providing a tensile strength of 15 MPa, plasticity of 52%, and water vapor permeability of 0.94 × 10⁻⁹ g/m s Pa. With further increase of chitin nanofibers content, films with layered and discontinuous phases are obtained, which negatively influence tensile strength and water vapor permeability. Moreover, only films containing both ferulic acid and chitin nanofibers demonstrated antibacterial activity toward E. coli and S. aureus, suggesting that the presence of fibers allows easier release of ferulic acid from the matrix. These results imply that the investigated three-component systems have potential applicability as sustainable active food packaging materials. Full article

Background/Objectives: A nanostructured membrane of polycaprolactone (a synthetic polymer) was synthesized using an electrospinning technique aiming to enhance its hydrophilicity and rate of degradation by surface modification via aminolysis. Since polycaprolactone nanofibrous films are naturally hydrophobic and with slow degradation, which restricts their use in biological systems, amino groups were added to the fiber surface using the aminolysis technique, greatly increasing the wettability of the membranes. Methods: Polycaprolactone nanofibrous membranes were synthesized via the electrospinning technique and surface modification by aminolysis. Trypsin, pepsin, and pancreatin were conjugated onto the aminolyzed PNF surface to further strengthen biocompatibility by enhancing the hydrophilicity, porosity, and biodegradation rate. SEM, FTIR, EDX, and liquid displacement method were performed to investigate proteolytic efficiency and morphological and physical characteristics such as hydrophilicity, porosity, and degradation rates. Results: Enzyme activity tests, which showed a zone of clearance, validated the successful enzyme conjugation and stability over a wide range of pH and temperatures. Scanning electron microscopy (SEM) confirms the smooth morphology of nanofibers with diameters ranging from 150 to 950 nm. Fourier transform infrared spectroscopy (FTIR) revealed the presence of O–H, C–O, C=O, C–N, C–H, and O–H functional groups. Energy-dispersive X-ray (EDX) elemental analysis indicates the presence of carbon, oxygen, and nitrogen atoms owing to the presence of peptide and amide bonds. The liquid displacement technique and contact angle proved that Pepsin-PNFs possess notably increased porosity (88.50% ± 0.31%) and hydrophilicity (57.6° ± 2.3 (L), 57.9° ± 2.5 (R)), respectively. Pancreatin-PNFs demonstrated enhanced enzyme activity and degradation rate on day 28 (34.61%). Conclusions: These enzyme-conjugated PNFs thus show improvements in physicochemical properties, making them ideal candidates for various biomedical applications. Future studies must aim for optimization of enzyme conjugation and in vitro and in vivo performance to investigate the versatility of these scaffolds. Full article

This study aimed to develop and characterize biodegradable films based on potato starch reinforced with carboxymethylcellulose (CMC) and polyethylene oxide (PEO) nanofibers, with the goal of improving their mechanical and thermal properties for potential use in sustainable packaging. The films were prepared through the thermal gelatinization of starch extracted from tubers, combined with nanofibers obtained by electrospinning CMC synthesized from potato starch. Key electrospinning variables, including solution concentration, voltage, distance, and flow rate, were analyzed. The films were morphologically characterized using scanning electron microscopy (SEM) and chemically analyzed by Fourier Transform Infrared Spectroscopy (FTIR) and X-ray Diffraction (XRD), and their thermal properties were assessed by Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). The results indicated an increase in tensile strength to 14.1 MPa in the reinforced films, compared to 13.6 MPa for pure starch and 7.1 MPa for the fiber-free CMC blend. The nanofibers had an average diameter of 63.3 nm and a porosity of 32.78%. A reduction in crystallinity and more stable thermal behavior were also observed in the composite materials. These findings highlight the potential of using agricultural waste as a functional reinforcement in biopolymers, providing a viable and environmentally friendly alternative to synthetic polymers. Full article

Active packaging films have been an essential component in food material research to ensure the safe and efficient preservation of food, fruit, and vegetables. The shelf life of fruits and vegetables may likely be extended by covering them with high-performance nanofiber (NF) films. The selection of materials for active packaging film has been a critical factor in preventing food materials from environmental contaminants (microbes) and extending the shelf life. This study aims to develop NF-based materials for cherry tomatoes to prevent fungal and bacterial damage. Bioactive NFs were produced through an electrospinning process using tannic acid (TA) within a polyvinylidene fluoride (PVDF) template. These NFs offer a sustainable alternative to synthetic packaging for food preservation. TA was incorporated into the PVDF matrix at varying concentrations (0.4 to 1.2%). Key parameters, including moisture content, thickness, opacity, water-contact angle, and thermal shrinkage, were assessed. The physicochemical results indicate that the TA NFs are suitable for further shelf-life performance evaluations. The antifungal and antibiofilm activity of the NFs was tested, showing that the TA_1.2 in the PVDF matrix was more effective than other concentrations. Shelf-life tests demonstrated that cherry tomatoes covered with TA_1.2 NFs showed no surface changes for up to 4 days. Importantly, the NFs were confirmed to be non-toxic to normal cells, as evidenced by tests on mouse 3T3-L1 fibroblast cells. In summary, we have developed bioactive NFs composed of TA in a PVDF matrix that enhance the shelf life of cherry tomatoes by preventing bacterial and fungal attacks on the fruit surfaces. Full article

Triboelectric nanogenerators (TENGs), as an emerging energy harvesting device, can efficiently convert the weak mechanical energy in the environment into electrical energy, demonstrating significant potential in self-powered systems. In this study, polyvinylidene fluoride (PVDF) nanofiber films mixed with a small amount of n-propyl gallate (PG) were prepared by using the electrospinning technique, and TENGs were fabricated based on these films. Unexpectedly, experimental results showed that PG (with 0.5–2.5 wt%) did not affect the β phase of the PVDF. However, the TENG based on PVDF/PG composite nanofiber film with 1 wt% PG (PG1-TENG) exhibited large output values of 334 V, 4.36 μA, and 78.4 nC for output voltage, current, and transferred charge, respectively, with a power density of 5.27 W/m², which highlights ~60% improvement in output voltage over pristine PVDF-TENG. This observation was attributed to the unique charge regulation ability of PG, without altering PVDF’s β phase. Furthermore, application potential of PG1-TENG was demonstrated by powering up an LCD calculator and 480 LEDs. Full article

Graphene oxide (GO) films have attracted significant attention due to their potential in separation and filtration applications. Based on their unique lamellar structure and ultrathin nature, GO films are difficult to maintain in a free-standing form and typically require substrate support. Consequently, understanding their film formation behavior and mechanisms on substrates is of paramount importance. This work employs commonly used nonwoven fibrous membranes as substrates and guided by the coffee-ring theory, systematically investigates the film formation behaviors, film morphology, and underlying mechanisms of GO films on fibrous membranes with varying wettability. Fibrous membranes with different wetting properties—hydrophilic, hydrophobic, and superhydrophobic—were prepared via electrospinning and initiated chemical vapor deposition (iCVD) surface modification techniques. The spreading behaviors, deposition dynamics, capillary effects, and evaporation-induced film formation mechanisms of GO suspensions on these substrates were thoroughly examined. The results showed that GO formed belt-like, ring-like, and circular patterns on the three fibrous membranes, respectively. GO films encapsulated more than the upper half, approximately the upper half, and the top portion of fibers, respectively. Pronounced wrinkling of GO films was observed except for those on the hydrophilic fibrous membrane. This work demonstrates that tuning the wettability of fibrous substrates enables precise control over GO film morphology, including fiber encapsulation, wrinkling, and coverage area. Furthermore, it deepens the understanding of the interactions between 1D nanofibers and 2D GO sheets at low-dimensional scales, laying a foundational basis for the optimized design of membrane engineering. Full article

Chlorpheniramine maleate (CPM) is a first-generation antihistamine that is frequently used to treat allergic reactions. However, excessive consumption presents potential health risks. Therefore, it is crucial to develop a quick and precise technique for identifying CPM levels. In this study, nickel cobalt phosphide (NiCoP), a binary metal phosphide, was successfully incorporated into carbon nanofibers. This involved creating a pore structure by adding polyvinylpyrrolidone (PVP) as a pore-forming template to a polyacrylonitrile (PAN) substrate via electrostatic spinning. An innovative electrochemiluminescent sensor for CPM detection was constructed using NiCoP/PVP/PAN carbon nanofibers (NiCoP/PVP/PAN/CNFs). Under optimal conditions, the electrochemical behavior of CPM was studied using NiCoP/PVP/PAN/CNF-modified working electrodes. These findings demonstrate that the three-dimensional porous network architecture of NiCoP/PVP/PAN/CNFs enhances the conductive properties of the material. Consequently, an electrochemical optical sensor fabricated using this structure exhibited remarkable performance. The linear detection range of the sensor was 1 × 10⁻⁸–7 × 10⁻⁵ mol/L, and the detection limit was 7.8 × 10⁻¹⁰ mol/L. When human urine and serum samples were examined, the sensor was found to have a high recovery rate (94.35–103.36%), which is promising for practical applications. Full article

The increasing demand for safe, cost-effective, and sustainable energy storage solutions has spotlighted aqueous zinc-ion batteries (AZIBs) as promising alternatives to lithium-ion systems. However, the practical deployment of AZIBs remains hindered by dendritic growth, hydrogen evolution, and surface corrosion at the zinc metal anode, which severely compromise electrochemical stability. In this study, we propose an interfacial engineering strategy involving ultrathin diamond-like carbon (DLC) coatings applied to Zn anodes. The DLC films serve as conformal, ion-permeable barriers that mitigate parasitic side reactions and facilitate uniform Zn plating/stripping behavior. Materials characterizations of the DLC layer on the Zn anodes revealed the tunability of sp²/sp³ hybridization and surface morphology depending on DLC thickness. Electrochemical impedance spectroscopy demonstrated a significant reduction in interfacial resistance, particularly in the optimally coated sample (DLC2, ~20 nm), which achieved a favorable balance between mechanical integrity and ionic transport. Symmetric-cell tests confirmed enhanced cycling stability over 160 h, while full-cell configurations with an ammonium vanadate nanofiber-based cathode exhibited superior capacity retention over 900 cycles at 2 A g⁻¹. The DLC2-coated Zn anodes demonstrated the most effective performance, attributable to its moderate surface roughness, reduced disorder, and minimized charge-transfer resistance. These results provide insight into the importance of fine-tuning the DLC thickness and carbon bonding structure for suppressing dendrite formation and enhancing electrochemical stability. Full article

This paper presents the effect of wood treatment with cellulose nanofibers on its parameters. The wettability, color changes (also after UV+IR radiation), equilibrium moisture content and mechanical parameters of wood treated with cellulose nanofibers (CNF) in three concentrations (0.5, 1 and 2%) were determined. Wood treatment with CNF increased the wettability of its surface, as evidenced by lower values of the contact angle (24.3–56.3 degrees) compared to untreated wood (98.3 degrees). The SEM images indicated the formation of cellulose nanofiber networks on the wood surface, especially in the case of 2% CNF-treated wood, which formed a well-adhered and homogenous film. Wood treated with 0.5% CNF showed a lower total color change (∆E*) value (1.9) after aging compared to untreated wood (2.9), indicating that the color changes in the treated wood were very small and recognizable only to an experienced observer, while the color differences in the control wood were recognizable to an inexperienced observer. Furthermore, CNF showed no negative effect on the strength parameters of the treated wood and only slightly affected the equilibrium moisture content for both sorption phases over the entire relative humidity range compared to control samples. The results prove the effective use of cellulose nanofibers in wood treatment, which can be an ecological and non-toxic component of wood protection systems. Full article

In this study, polyvinyl alcohol (PVA) films were reinforced with lignocellulosic nanofibers (LCNFs) extracted from bamboo shoot shells using a choline chloride-based deep eutectic solvent (DES). A filler loading of 10 wt% was identified as the optimal condition for enhancing film performance. To improve interfacial compatibility between the PVA matrix and LCNFs, three surface modification treatments were applied to the nanofibers: hydrochloric acid (HCl) hydrolysis, citric acid (CA) crosslinking, and a dual modification combining both methods (HCl&CA). Among all formulations, films incorporating dual-modified LCNF at 10 wt% loading exhibited the most significant improvements. Compared to neat PVA, these composites showed a 79.2% increase in tensile strength, a 15.1% increase in elongation at break, and a 33.1% enhancement in Young’s modulus. Additionally, thermal stability and barrier properties were improved, while water swelling and solubility were reduced. Specifically, the modified films achieved a thermal residue of 9.21% and the lowest degradation rate of 10.81%/min. Water vapor transmission rate and oxygen permeability decreased by 18.8% and 18.6%, respectively, and swelling and solubility dropped to 14.26% and 3.21%. These results highlight the synergistic effect of HCl hydrolysis and CA crosslinking in promoting uniform filler dispersion and strong interfacial adhesion, offering an effective approach to valorizing bamboo shoot shell waste into high-performance, eco-friendly packaging materials. Full article

Wound dressings have a significant role in managing trauma-related injuries, chronic lacerations, as well as post-operative complications, by preventing infections and promoting tissue regeneration. Conventional methods using sutures and gauze often pose constraints in healing effectiveness and cost. Emerging materials, particularly cellulose-based nanofibers, offer a favorable choice due to their biodegradability, biocompatibility, and structural similarity to the extracellular matrix. Cellulose, being an abundant, naturally available biopolymer, forms the basis for modern materials for wound dressing. It is a very resourceful material due to its capability to be processed into films, fibers, and membranes with tailored properties. Surface modification of cellulose membranes with nanoparticles or bioactive compounds assists in enhancing the antimicrobial properties and supports sustained drug release, essential in chronic wound infections. Electrospinning and other modern fabrication techniques allow for controlling the fiber morphology and drug-delivery characteristics. This review highlights the properties, fabrication techniques, surface functionalization, and biomedical applications of cellulose-based materials in wound care. With increasing demand for effective and cost-effective wound treatments, cellulose nanofibers stand out as a sustainable, multifunctional platform for cutting-edge wound dressings, offering improved healing, reduced scarring, and potential for amalgamation with several drug delivery and tissue engineering approaches. Full article

Bacterial cellulose (BC) is a polysaccharide produced by Gram-positive and Gram-negative bacteria with a strictly aerobic metabolism, having a huge number of significant applications in the biomedical field. This study investigates the development of bacterial cellulose (BC)-based composite systems that incorporate cerium dioxide nanoparticles (CeO₂ NPs) used as antibacterial agents to enhance wound healing, particularly for burn treatments. The innovation of this study resides in the integration of CeO₂ NPs synthesized by using a precipitation method using both chemical and green reducing agents, ammonium hydroxide (NH₄OH) and turmeric extract (TE), in BC membranes composed of ultrathin nanofibers interwoven into a three-dimensional network appearing as a hydrogel mass. Characterization by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and Fourier-transform infrared spectroscopy (FTIR) confirmed the effective deposition of this agent onto the BC matrix. Antibacterial activity tests against E. coli and B. subtilis indicated strong inhibition for the composites synthesized following these routes, particularly for the BC-CeO₂-TE-OH sample, processed by employing both precipitating agents. Cytotoxicity evaluations showed no inhibition of cell activity. Additionally, loading the composites with dexamethasone endowed them with analgesic release over 4 h, as observed through ultraviolet–visible spectroscopy (UV-Vis), while the FTIR spectra revealed a sustained drug presence post-release. These findings highlight BC-based films as promising candidates for advanced wound care and tissue engineering applications. Full article

With the recent development of advanced industries, in addition to simple abrasions, the demand for wound dressing is gradually increasing in fields such as diabetes care. Factors affecting wound healing include pH, temperature, genetic factors, stress, smoking, and obesity, and studies on these are also increasing. In addition, studies on hydrogels, electrospun nanofibers, foams, films, plant-based materials, chitosan, gelatin, 3D printing, and chemosensors for wound healing are also increasing. However, although there are many data related to wound healing, there are not many studies that have systematically divided them into structures, materials, and monitoring through a review of the literature. Therefore, based on various studies on wound healing, wound-healing materials were classified into structures (films, foams, gauzes, and electrospun nanofibers), chemical materials, nature-based materials, and monitoring sensors, and a literature review was conducted. Full article

Objectives: In this study, we aimed to incorporate levocetirizine dihydrochloride (LVC) into electrospun nanovesicle-in-nanofiber (NF) scaffolds for combined management of atopic dermatitis and methicillin-resistant Staphylococcus Aureus skin infection, to sustain LVC release for continuous skin improvement. Methods: Firstly, LVC was encapsulated in cerosomes (CERs) by employing a thin-film hydration approach using a 2¹.3¹ factorial design. CERs were assessed by calculating entrapment efficiency (EE%), particle size (PS) and polydispersity index (PDI). In addition, the optimized CERs were further subjected to stability evaluation. After that, the optimized CERs were incorporated into polyurethane nanofibers (NFs) using a coaxial electrospinning technique. An in vitro release assay was used to calculate the amount of LVC released from the LVC-NFs and the optimized CERs-NFs. For morphological assessment of NFs, LVC-NFs and CERs-NFs were subjected to transmission electron microscopy, scanning electron microscopy, and confocal laser scanning microscopy. Atomic force microscopy was utilized to evaluate the roughness of CERs and both NFs. The optimum formulation was further subjected to in vivo study. Results: The optimum CERs exhibited an EE% of 65.03 ± 1.07%, a PS of 680.00 ± 39.50 nm, and a PDI of 0.51 ± 0.04. LVC was released in a sustained manner from CERs NFs. Further, a dermatokinetic study confirmed that CERs-NFs sustained the infiltration of LVC, compared with the other groups. Finally, a safety assessment showed that all formulations were safe when topically applied to rat skin. Conclusions: In conclusion, AD and MRSA skin infections may be cured by employing electrospun nanofiber-scaffold-loaded LVC CERs, which can thus be regarded as a promising system. Full article