Highly water-resistant paper via infiltration with polymeric microspheres from nanocellulose-stabilized plant oil-derived monomer.

Sustainable strategies to improve the water resistance of cellulose paper are actively sought. In this work, polymeric microspheres (PMs), prepared through emulsion polymerization of cellulose nanofibers stabilized rubber seed oil-derived monomer, were investigated as coatings on corrugated medium paper (CMP). After infiltrating porous paper with PMs, the water-resistant corrugated papers (WRCPn) with enhanced mechanical properties were obtained. When 30 wt% PMs were introduced, WRCP30 turned out to be highly compacted with an increased water contact angle of 106.3° and a low water vapor transmission rate of 81 g/(m2 d) at 23 °C. Meanwhile, the tensile strength of WRCP30 increased to 22.2 MPa, a 4-fold increase from CMP. When tested in a well-hydrated state, 71% of its mechanical strength in the dry state was maintained. Even with a low content of 10 wt% PMs, WRCP10 also exhibited stable tensile strength and water wettability during the cyclic soaking-drying process. Thus, the plant oil based sustainable emulsion polymers provide a convenient route for enhancing the overall performance of cellulose paper.

Membranes composed of poly(lactic acid)/poly(ethylene glycol) and Ora-pro-nóbis (Pereskia aculeata Miller) extract for dressing applications.

Wounds are considered one of the most critical medical conditions that must be managed appropriately due to the psychological and physical stress they cause for patients, as well as creating a substantial financial burden on patients and global healthcare systems. Nowadays, there is a growing interest in developing nanofiber mats loaded with varying plant extracts to meet the urgent need for advanced wound ressings. This study investigated the development and characterization of poly(lactic acid) (PLA)/ poly(ethylene glycol) (PEG) nanofiber membranes incorporated with Ora-pro-nóbis (OPN; 12.5, 25, and 50 % w/w) by the solution-blow-spinning (SBS) technique. The PLA/PEG and PLA/PEG/OPN nanofiber membranes were characterized by scanning electron microscopy (SEM), thermal properties (TGA and DSC), Fourier transform infrared spectroscopy (FTIR), contact angle measurements and water vapor permeability (WVTR). In addition, the mats were analyzed for swelling properties in vitro cell viability, and fibroblast adhesion (L-929) tests. SEM images showed that smooth and continuous PLA/PEG and PLA/PEG/OPN nanofibers were obtained with a diameter distribution ranging from 171 to 1533 nm. The PLA/PEG and PLA/PEG/OPN nanofiber membranes showed moderate hydrophobicity (~109-120°), possibly preventing secondary injuries during dressing removal. Besides that, PLA/PEG/OPN nanofibers exhibited adequate WVTR, meeting wound healing requirements. Notably, the presence of OPN gave the PLA/PEG membranes better mechanical properties, increasing their tensile strength (TS) from 3.4 MPa (PLA/PEG) to 5.3 MPa (PLA/PEG/OPN), as well as excellent antioxidant properties (Antioxidant activity with approximately 45 % oxidation inhibition). Therefore, the nanofiber mats based on PLA/PEG, especially those incorporated with OPN, are promising options for use as antioxidant dressings to aid skin healing.

Dual Self-Assembly of Puerarin and Silk Fibroin into Supramolecular Nanofibrillar Hydrogel for Infected Wound Treatment.

The treatment of infected wounds remains a challenging biomedical problem. Some bioactive small-molecule hydrogelators with unique rigid structures can self-assemble into supramolecular hydrogels for wound healing. However, they are still suffered from low structural stability and bio-functionality. Herein, a supramolecular hydrogel antibacterial dressing with a dual nanofibrillar network structure is proposed. A nanofibrillar network created by a small-molecule hydrogelator, puerarin extracted from the traditional Chinese medicine Pueraria, is interconnected with a secondary macromolecular silk fibroin nanofibrillar network induced by Ga ions via charge-induced supramolecular self-assembly. The resulting hydrogel features adequate mechanical strength for sustainable retention at wounds. Good biocompatibility and efficient bacterial inhibition are obtained when the Ga ion concentration is 0.05%. Otherwise, the substantial release of Ga ions and puerarin endows the hydrogel with excellent hemostatic and antioxidative properties. In vivo, evaluation of a mouse-infected wound model demonstrates that its healing effect outperformed that of a commercially available silver-containing wound dressing. The experimental group successfully achieves a 100% wound closure rate on day 10. This study sheds new light on the design of nanofibrillar hydrogels based on supramolecular self-assembly of naturally derived bioactive molecules as well as their clinical use for treating chronic infected wounds.

Orally fast dissolving α-lipoic acid electrospun nanofibers mitigates lipopolysaccharide induced inflammation in RAW 264.7 macrophages.

α-Lipoic acid (LA), a dietary supplement known for its strong antioxidant and anti-inflammatory potential, faces challenges due to its poor aqueous solubility and thermal instability. To address these issues, herein methyl-beta-cyclodextrin (M-ß-CD) was utilized to create inclusion complex (IC) of LA in 1:1 M stoichiometric ratio of M-ß-CD to LA. The LA-M-ß-CD-IC was further combined with pullulan (PUL), a non-toxic and water-soluble biopolymer, for the development of electrospun nanofibers (NF) by green and sustainable approach. The resulting PUL/LA/M-ß-CD NF formed as a self-standing and flexible material with an average diameter of 569 ± 129 nm and encapsulation efficiency of ∼86.90 %. The developed NF demonstrated an accelerated release, quick dissolution, and disintegration when exposed to artificial saliva replicating the conditions of oral cavity. PUL/LA/M-ß-CD NF attenuated the production of ROS and NO by downregulating pro-inflammatory enzymes (iNOS and COX-2) in lipopolysaccharide (LPS) stimulated RAW 264.7 cells. Moreover, PUL/LA/M-ß-CD NF also significantly downregulated the expression of pro-inflammatory cytokines including TNF-α, IL-6, and IL-1ß along with suppression of NF-ĸB nuclear translocation in comparison to LA (at 250 µM). In nutshell, PUL/LA/M-ß-CD NF demonstrated great potential as a rapid disintegrating delivery system for oral anti-inflammatory treatment due to the enhanced physicochemical characteristics of LA.

Nanographene-Au fine-tuning to intensify plasmonic-resonance of polymeric hybrid bionanosystem for synergistic phototherapy and nerve photobiomodulation.

Here, we report the multi-photo-bioactivity of the plasmonic-nano graphitic coordinated polycaprolactone-based aligned nanofibrous scaffolds-based bionanosystem for photothermal breast and colon cancer therapies and peripheral nerve photobiomodulation. The size-optimized colloidal reduced graphene oxide (nRGO, 180 nm) nanosheets, for enhanced photothermal impact, were surface-functionalized with gold nanospheres (AuNPs) to prepare the nRGO@AuNP monodispersed nano-composite and then doped 2.0 mg of nRGO@AuNP in biocompatible and biodegradable polymer polycaprolactone (PCL) to fabricate the nRGO@AuNP-PCL (2.0 mg) plasmonic aligned nanofibrous scaffolds. More than 90% of cancer cells, breast cancer (MCF-7) as well as colon cancer (CT-26), ablated after 5 min of low NIR (808 nm) laser power (0.72 W/cm2) illumination with nRGO@AuNP-PCL (2.0 mg) aligned nanofibrous scaffolds. Besides, the nRGO@AuNP-PCL (2.0 mg) provided an extraordinary microenvironment for adhesion, nerve growth, proliferation, and differentiation of PC12 and S42 cells which mimics the natural extracellular matrix. The 2.5-fold increase in neurite length was observed with NIR illumination after 3 days whereas 1.7-fold was found without NIR illumination after 7 days in comparison to PCL (pure). The current findings will be useful to provide a new crucial approach for preparing biocompatible multifunctional composite plasmonic nanofibers as a highly efficient distinct platform for photothermal therapies and promising bioimplants to overcome the loss of sensation after cancer surgery through nerve photobiomodulation.

Wireless electrostimulation for cancer treatment: An integrated nanoparticle/coaxial fiber mesh platform.

Cancer, namely breast and prostate cancers, is the leading cause of death in many developed countries. Controlled drug delivery systems are key for the development of new cancer treatment strategies, to improve the effectiveness of chemotherapy and tackle off-target effects. In here, we developed a biomaterials-based wireless electrostimulation system with the potential for controlled and on-demand release of anti-cancer drugs. The system is composed of curcumin-loaded poly(3,4-ethylenedioxythiophene) nanoparticles (CUR/PEDOT NPs), encapsulated inside coaxial poly(glycerol sebacate)/poly(caprolactone) (PGS/PCL) electrospun fibers. First, we show that the PGS/PCL nanofibers are biodegradable, which allows the delivery of NPs closer to the tumoral region, and have good mechanical properties, allowing the prolonged storage of the PEDOT NPs before their gradual release. Next, we demonstrate PEDOT/CUR nanoparticles can release CUR on-demand (65 % of release after applying a potential of -1.5 V for 180 s). Finally, a wireless electrostimulation platform using this NP/fiber system was set up to promote in vitro human prostate cancer cell death. We found a decrease of 67 % decrease in cancer cell viability. Overall, our results show the developed NP/fiber system has the potential to effectively deliver CUR in a highly controlled way to breast and prostate cancer in vitro models. We also show the potential of using wireless electrostimulation of drug-loaded NPs for cancer treatment, while using safe voltages for the human body. We believe our work is a stepping stone for the design and development of biomaterial-based future smarter and more effective delivery systems for anti-cancer therapy.

Study on synergistic mechanism of molybdenum disulfide/sodium carboxymethyl cellulose composite nanofiber mats for photothermal/photodynamic antibacterial treatment.

Innovative antibacterial therapies using nanomaterials, such as photothermal (PTT) and photodynamic (PDT) treatments, have been developed for treating wound infections. However, creating secure wound dressings with these therapies faces challenges. The primary focus of this study is to prepare an antibacterial nanofiber dressing that effectively incorporates stable loads of functional nanoparticles and demonstrates an efficient synergistic effect between PTT and PDT. Herein, a composite nanofiber mat was fabricated, integrating spherical molybdenum disulfide (MoS2) nanoparticles. MoS2 was deposited onto polylactic acid (PLA) nanofiber mats using vacuum filtration, which was further stabilized by sodium carboxymethyl cellulose (CMC) adhesion and glutaraldehyde (GA) cross-linking. The composite nanofibers demonstrated synergistic antibacterial effects under NIR light irradiation, and the underlying mechanism was explored. They induce bacterial membrane permeability, protein leakage, and intracellular reactive oxygen species (ROS) elevation, ultimately leading to >95 % antibacterial activity against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), which is higher than that of single thermotherapy (almost no antibacterial activity) or ROS therapy (about 80 %). In addition, the composite nanofiber mats exhibited promotion effects on infected wound healing in vivo. This study demonstrates the great prospects of composite nanofiber dressings in clinical treatment of bacterial-infected wounds.

Electrospun nanofibers based on zein and red onion bulb extract (Allium cepa, L.): Volatile compounds, hydrophilicity, and antioxidant activity.

Onion is rich in bioactive and volatile compounds with antioxidant activity. However, the pungent odor of volatile compounds (VOCs) released restricts its use. The encapsulation of red onion extract by electrospinning is an alternative to mask this odor and protect its bioactive compounds. The main objective of this study was to encapsulate red onion bulb extract (ROE) in different concentrations into zein nanofibers by electrospinning and evaluate their thermal, antioxidant, and hydrophilicity properties. The major VOC in ROE was 3(2H)-furanone, 2-hexyl-5-methyl. Incorporating ROE into the polymeric solutions increased electrical conductivity and decreased apparent viscosity, rendering nanofibers with a lower average diameter. The loading capacity of ROE on fibers was high, reaching 91.5% (10% ROE). The morphology of the nanofibers was random and continuous; however, it showed beads at the highest ROE concentration (40%). The addition of ROE to the nanofibers increased their hydrophilicity. The nanofibers' antioxidant activity against 2,2-diphenyl-1-picrylhydrazyl, nitric oxide, and hydroxyl radicals ranged from 32.5% to 57.3%. The electrospun nanofibers have the potential to protect and mask VOCs. In addition, they offer a sustainable alternative to the synthetic antioxidants commonly employed in the food and packaging industry due to their antioxidant activities.

Pickering emulsions of thyme oil in water using oxidized cellulose nanofibers: Towards bio-based active packaging.

The antioxidant and antimicrobial properties of thyme essential oil (TEO) are useful for active food packaging, but its poor aqueous solubility restricts its applications. This work involves anionic cellulose nanofibers (CNFs) as the sole stabilizing agent for TEO-in-water emulsions, with oil concentrations ranging from 10 mL/L to 300 mL/L. A double mechanism was proposed: the adsorption of CNFs at oil/water interfaces restricted coalescence to a limited extent, while thickening (rheological stabilization) was required to avoid the buoyance of large droplets (>10 µm). Thickening effects comprised both higher viscosity (over 0.1 Pa·s at 10 s-1) and yield stress (approximately 0.9 Pa). Dilute emulsions had good film-forming capabilities, whereas concentrated emulsions were suitable for paper coating. Regarding antimicrobial activity, CNF-stabilized TEO-in-water emulsions successfully inhibited the growth of both Gram-negative (E. coli, S. typhimurium) and Gram-positive bacteria (L. monocytogenes). As for the antioxidant properties, approximately 50 mg of paper or 3-5 mg of film per mL of food simulant D1 were required to attain 50 % inhibition in radical scavenging tests. Nonetheless, despite the stability and the active properties of these bio-based hydrocolloids, providing this antioxidant and antimicrobial activity was incompatible with maintaining the organoleptic properties of the foodstuff unaltered.

Preparation and functionalization of cellulose nanofibers using a naturally occurring acid and their application in stabilizing linseed oil/water Pickering emulsions.

Finding efficient and environmental-friendly methods to produce and chemically modify cellulose nanofibers (CNFs) remains a challenge. In this study, lactic acid (LA) treatment followed by microfluidization was employed for the isolation and functionalization of CNFs. Small amounts of HCl (0.01, 0.1, and 0.2 M) were used alongside LA to intensify cellulose hydrolysis. FTIR spectroscopy and solid-state 13C NMR confirmed the successful functionalization of CNFs with lactyl groups during isolation, while SEM, AFM, and rheological tests revealed that the addition of HCl governed the fibers' sizes and morphology. Notably, the treatment with LA and 0.2 M HCl resulted in a more efficient defibrillation, yielding smaller nanofibers sizes (62 nm) as compared to the treatment with LA or HCl alone (90 and 108 nm, respectively). The aqueous suspension of CNFs treated with LA and 0.2 M HCl showed the highest viscosity and storage modulus. LA-modified CNFs were tested as stabilizers for linseed oil/water (50/50 v/v) emulsions. Owing to the lactyl groups grafted on their surface and higher aspect ratio, CNFs produced with 0.1 and 0.2 M HCl led to emulsions with increased stability (a creaming index increase of only 3 % and 1 %, respectively, in 30 days) and smaller droplets sizes of 23.4 ± 1.2 and 35.5 ± 0.5 µm, respectively. The results showed that LA-modified CNFs are promising stabilizers for Pickering emulsions.

Poly(vinyl alcohol) /Alginate nanofibrous mats containing Malva Sylvestris extract: Synthesis, characterization, in vitro and in vivo assessments for burn wound applications.

An important part of wound healing is providing effective wound care, coupled with preventing wound infection, which slows or disrupts healing. There are currently many herbal plants that have historical supernatural properties that show remarkable wound healing abilities. These herbal extracts have shown promising results when applied to electrospun nanofibrous mats platforms for wound healing. Accordingly, Malva Sylvestris extract (MS) was electrospun into polyvinyl alcohol/alginate nanofibrous mats (PVA/ALG). Field Emission Scanning Electron Microscopy (FESEM) demonstrated that the fiber diameter ranged from approximately 100-200 nm in nanofibrous mats, with a uniform appearance without beads. MS extract was detected in nanofibrous mats by Fourier Transform Infrared Spectroscopy (FTIR). A major benefit of incorporating MS extract into PVA/ALG nanofibrous mats is that their alterations have resulted in enhanced mechanical characteristics. The nanofibrous mats containing MS extracts showed significantly increased antibacterial efficacy against Gram-positive and Gram-negative bacteria. Based on the findings from in vivo experiments, the PVA/ALG/MS1 (M2) dressing demonstrated a wound closure rate of 93-94 % within 21 days of treatment in rats, indicating its significant potential for use as a wound dressing agent in the treatment of burn injuries. The combination of PVA, ALG, and MS1 in this nanofibrous mats exhibited beneficial properties, including biocompatibility, suitable mechanical strength, and the ability to promote cellular proliferation and angiogenesis, further validating its effectiveness as a wound healing dressing.

Regulation of the colon-targeted release rate of lactoferrin by constructing hydrophobic ethyl cellulose/pectin composite nanofibrous carrier and its effect on anti-colon cancer activity.

In order to modify colonic release behavior of lactoferrin (Lf), a hydrophobic composite nanofibrous carrier (CNC) was constructed by emulsion coaxial electrospinning. Ethylcellulose/pectin based water-in-oil emulsion and Lf-contained polyvinyl alcohol solution were used as shell and core fluids, respectively. An electrospinning diagram was first constructed to screen out suitable viscosity (51-82 cP) and conductivity (960-1300 µS/cm) of the dispersed phase of pectin solution for successful electrospinning of shell emulsion. Varying mass fraction of pectin solution (5 %-20 %) of shell emulsion during emulsion coaxial electrospinning obtained CNCs with different micro-structures, labeled as 5&95 CNC, 10&90 CNC, 15&85 CNC, 20&80 CNC. These CNCs all achieved colonic delivery of Lf (>95 %), and the time for complete release of Lf in simulated colon fermentation process were 10, 7, 5 and 3 h, respectively. That is, the greater the pectin content in CNC, the faster the release rate of stabilized Lf in colon. Lf release in simulated colon fermentation fluid involved complex mechanisms, in which diffusion release of Lf was dominant. Increasing colonic release rate of Lf enhanced its regulation effect on the expression levels of cell cycle arrest and apoptosis-related protein and promote its effective inhibition on the proliferation of HCT116 cell.

High mechanical property and hydrophilic electrospun poly amidoxime/poly acrylonitrile composite nanofibrous mats for extraction uranium from seawater.

Seawater reserves about 4.5 billion tons of uranium, if properly extracted, could be a sustainable green energy resource for hundreds of years, alternating its limited terrestrial ore and reducing the CO2 emitted from fossil fuels. The current seawater uranium adsorbents suffer neither economically viable nor adsorption efficiency, requiring more development to harvest satisfactorily uranium from seawater. Amidoxime-based fibrous adsorbents are the most promising adsorbents of seawater uranium due to abundant chelating sites. However, they suffer from severe shrinkage and stiffness once they dry, losing porous architecture and mechanical properties. Herein, an economical and scalable two-nozzle electrospinning technology was applied to produce poly amidoxime nanofibers (PAO NFs) supported by Poly acrylonitrile nanofibers (PAN NFs) as composite PAO/PAN nanofibrous mats with high structure stability. These PAO/PAN mats, with rapid wettability and excellent mechanical strength, show promising uranium adsorption capacities of 369.8 mg/g at seawater pH level, much higher than PAO and PAN NFs. The uranium adsorption capacity of the PAO/PAN mat reached 5.16 mg/g after 7 days of circulating (10 ppm uranium) spiked natural seawater. Importantly, the composite mat maintained its fibrous structure after five adsorption-desorption cycles with more than 80 % of its adsorption capacity, confirming its recyclability and stability. Therefore, the composite PAO/PAN mat fulfills the basic requirements for effectively and economically trapping uranium from seawater, which could be a matrix for further development.

In vitro and in vivo studies of Dragon's blood plant (D. cinnabari)-loaded electrospun chitosan/PCL nanofibers: Cytotoxicity, antibacterial, and wound healing activities.

The D. cinnabari plant was loaded into the chitosan (Chn)/polycaprolactone (PCL) nanofibers in two forms: resin (D. cinnabari) and its ethyl acetate fraction. The Chn/PCL, Chn/PCL/D. cinnabari (CPD, 1, 3, and 5 %), and Chn/PCL/ethyl acetate extract D. cinnabari (CPED, 1, 3, and 5 %) showed no toxicity against human dermal fibroblast cells. The lactate dehydrogenase assay results indicated that the toxicity of pour, coated D. cinnabari, and CPED nanofibers were lower than 10 and 15 % after 1 and 3 days, respectively. The antibacterial results showed the inhibition zone for ethyl acetate extract D. cinnabari (ED-3 %), the Chn/PCL-2, and CPED3% nanofibers was 8.1, 7.4, 4.2, 5.1 mm, 12.8, 12.4, 21.7, 17.2 mm, and 24.7, 22.9, 37.1, 30.2 mm against S. aureus, B. subtilis, E. coli, and P. aeruginosa, respectively. The antibacterial activity results showed synergistic effect between the Chn/PCL and ethyl acetate extract D. cinnabari occurred. The diameter of wounds (1.50 × 1.50 cm diameter) made on the dorsal surface of rabbits reduced to 1.50 × 0.70, 0.50 × 0.30, 1.00 × 1.00, 0.60 × 0.50, 0.20 × 0.05, and 0.00 × 0.00 cm in the presence of ordinary gauze dressing, silver sulfadiazine, ED-3 %, Chn/PCL-2, CPD3%, and CPED3%nanofibers, respectively, after 14 days.

Selenium nanoparticles incorporated in nanofibers media eliminate H1N1 activity: a novel approach for virucidal antiviral and antibacterial respiratory mask.

The consecutive viral infectious outbreaks impose severe complications on public health besides the economic burden which led to great interest in antiviral personal protective equipment (PPE). Nanofiber-based respiratory mask has been introduced as a significant barrier to eliminate the airborne transmission from aerosols toward reduction the viral infection spreading. Herein, selenium nanoparticles incorporated in polyamide 6 nanofibers coated on spunbond nonwoven were synthesized via electrospinning technique (PA6@SeNPs), with an average diameter of 180 ± 2 nm. The nanofiber-coated media were tested for 0.3 µm particulate filtration efficiency based on Standard NIOSH (42 CFR 84). PA6@SeNPs had a pressure drop of 45 ± 2 Pa and particulate filtration efficiency of more than 97.33 which is comparable to the N95 respiratory mask. The bacterial killing efficiency of these nanofibers was 91.25% and 16.67% against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), respectively. Furthermore, the virucidal antiviral test for H1N1 infected Madin-Darby Canine Kidney cells (MDCK) exhibited TCID50 of 108.13, 105.88, and 105.5 for 2, 10, and 120 min of exposure times in comparison with 108.5, 107.5, and 106.5 in PA6 nanofibers as control sample. MTT assay indicated excellent biocompatibility of electrospun PA6@SeNP nanofibers on L292 cells. These results propose the PA6@SeNP nanofibers have a high potential to be used as an efficient layer in respiratory masks for protection against respiratory pathogens.

Incorporation of doxorubicin and CoFe2O4 nanoparticles into the cellulose acetate phthalate / polyvinyl alcohol (core)/ polyurethane (shell) nanofibers against A549 human lung cancer during chemotherapy/hyperthermia combined method.

Cellulose acetate phthalate (CAP)/polyvinyl alcohol (PVA)/polyurethane (PU) nanofibers were synthesized by simple and coaxial electrospinning (ES) processes. Doxorubicin (DOX) and the CoFe2O4 nanoparticles were loaded into the nanofibers. The performance of the prepared nanofibers was investigated for the sustained release of DOX against A541 lung cancer cells under chemotherapy/external magnetic field (EMF) and alternating magnetic field (AMF, hyperthermia treatment) combined methods in both the in vitro and in vivo conditions. The sustained release of DOX from core-shell nanofibers containing 5 wt% cobalt ferrite was obtained within 300, 600 h, at pH of 5.5 and 7.4 without AMF and 168, 360 h, under an alternating magnetic field (AMF). More than 98.3 ± 0.2 % of A549 cancer cells were killed in the presence of core-shell nanofibers containing 100 µg DOX and 5 % cobalt ferrite nanoparticles in the presence of AMF. The flowcytometric results indicated that only 19.1 and 8.85 % cancer cells remained alive under EMF and AMF, respectively. The in vivo results revealed in stopping the growth of tumor volume and decrease in the relative tumor volume up to 0.5 were obtained using magnetic core-shell nanofibers containing 100 µg DOX and 5 % cobalt ferrite nanoparticles in the presence of EMF and AMF, respectively.

Bioethanol lignin-rich residue from olive stones for electrospun nanostructures development and castor oil structuring.

This work describes the chemical and structural characterization of a lignin-rich residue from the bioethanol production of olive stones and its use for nanostructures development by electrospinning and castor oil structuring. The olive stones were treated by sequential acid/steam explosion pretreatment, further pre-saccharification using a hydrolytic enzyme, and simultaneous saccharification and fermentation (PSSF). The chemical composition of olive stone lignin-rich residue (OSL) was evaluated by standard analytical methods, showing a high lignin content (81.3 %). Moreover, the structural properties were determined by Fourier-transform infrared spectroscopy, nuclear magnetic resonance, and size exclusion chromatography. OSL showed a predominance of ß-ß' resinol, followed by ß-O-4' alkyl aryl ethers and ß-5' phenylcoumaran substructures, high molecular weight, and low S/G ratio. Subsequently, electrospun nanostructures were obtained from solutions containing 20 wt% OSL and cellulose triacetate with variable weight ratios in N, N-Dimethylformamide/Acetone blends and characterized by scanning electron microscopy. Their morphologies were highly dependent on the rheological properties of polymeric solutions. Gel-like dispersions can be obtained by dispersing the electrospun OSL/CT bead nanofibers and uniform nanofiber mats in castor oil. The rheological properties were influenced by the membrane concentration and the OSL:CT weight ratio, as well as the morphology of the electrospun nanostructures.

A double-layer cellulose/pectin-soy protein isolate-pomegranate peel extract micro/nanofiber dressing for acceleration of wound healing.

Multi-layered wound dressings can closely mimic the hierarchical structure of the skin. Herein, a double-layer dressing material is fabricated through electrospinning, comprised of a nanofibrous structure as a healing-support layer or the bottom layer (BL) containing pectin (Pec), soy protein isolate (SPI), pomegranate peel extract (P), and a cellulose (Cel) microfiber layer as a protective/monitoring layer or top layer (TL). The formation of a fine bilayer structure was confirmed using scanning electron microscopy. Cel/Pec-SPI-P dressing showed a 60.05 % weight loss during 7 days of immersion in phosphate buffered solution. The ultimate tensile strength, elastic modulus, and elongation at break for different dressings were within the range of 3.14-3.57 MPa, 32.26-36.58 MPa, and 59.04-63.19 %, respectively. The release of SPI and phenolic compounds from dressings were measured and their antibacterial activity was evaluated. The fabricated dressing was non-cytotoxic following exposure to human keratinocyte cells. The Cel/Pec-SPI-P dressing exhibited excellent cell adhesion and migration as well as angiogenesis. More importantly, in vivo experiments on Cel/Pec-SPI-P dressings showed faster epidermal layer formation, blood vessel generation, collagen deposition, and a faster wound healing rate. Overall, it is anticipated that the Cel/Pec-SPI-P bilayer dressing facilitates wound treatment and can be a promising approach for clinical use.

Fabrication of wound dressings: Herbal extract-loaded nanoliposomes embedded in fungal chitosan/polycaprolactone electrospun nanofibers for tissue regeneration.

Wound healing is a complex process and one of the major therapeutic and economic subjects in the pharmaceutical area. In recent years, the fabrication of nano-sized wound dressing models has attracted great attention for tissue regeneration. Plant extracts loaded nanoparticles are environmentally friendly and non-toxic and the release of the bioactive substance will be controlled to the wound area. This study aims to fabricate wound dressing models that contain bioactive components for tissue regeneration. Fungal chitosan/polycaprolactone nanofiber was fabricated by electrospinning and it has been characterized. Plant extracts loaded nanoliposomes were prepared, characterized, and embedded in nanofiber structures. The effectiveness of wound dressing models for tissue regeneration was evaluated by in vitro and in vivo studies. It was observed that all wound dressing models positively affect the cell viability of human dermal fibroblast cells. It was determined that plant extracts loaded nanoparticles embedded in nanofibers increased in cell viability than nanoparticles that were non-embedded in nanofiber structures. Histological analysis showed that plant extract-loaded nanoliposomes embedded in chitosan/PCL nanofibers were used for tissue regeneration. The most effective nanofibers were determined as Wd-ClNL nanofibers. RESEARCH HIGHLIGHTS: Hypericum perforatum L. and Cistus laurifolius L. were prepared by modified ultrasonic extraction method. Fungal chitosan/polycaprolactone nanofiber was fabricated by electrospinning and it has been characterized. Plant extract-loaded nanoliposomes were prepared, and characterized. They were embedded in chitosan/polycaprolactone nanofiber. Effects of the wound dressing model were analyzed by in vitro and in vivo assays for tissue regeneration.

MXene-Decorated Nanofibrous Membrane with Programmed Antibacterial and Anti-Inflammatory Effects via Steering NF-κB Pathway for Infectious Cutaneous Regeneration.

Although antibiotic is still the main choice for antibacteria both in hospital and community, phototherapy has become a possibly one of the alternative approaches in the treatment of microbe-associated infections nowadays because of its considerable potential in effective eradication of pathogenic bacteria. However, overwhelming reactive oxygen species (ROS) generated from phototherapy inevitably provoke an inflammatory response, complicating the healing process. To address this outstanding issue, a MXene-decorated nanofibrious is devised that not only yield localized heat but also elevate ROS levels under near-infrared laser exposure ascribed to the synergistic photothermal/photodynamic effect, for potent bacterial inactivation. After being further loaded with aspirin, the nanofibrous membranes exhibit benign cytocompatibility, boosting cell growth and suppressing the (nuclear factor kappa-B ( NF-κB) signaling pathways through RNA sequencing analysis, indicating an excellent anti-inflammatory effect. Interestingly, in vivo investigations also corroborate that the nanofibrous membranes accelerate infectious cutaneous regeneration by efficiently killing pathogenic bacteria, promoting collagen deposition, boosting angiogenesis, and dampening inflammatory reaction via steering NF-κB pathway. As envisaged, this work furnishes a decorated nanofibrous membrane with programmed antibacterial and anti-inflammatory effects for remedy of refractory bacteria-invaded wound regeneration.