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Three-dimensional scaffold-based culture has been increasingly gaining influence in oncology as a therapeutic strategy for tumors with a high relapse percentage. This study aims to evaluate electrospun poly(ε-caprolactone) (PCL) and poly(lactic acid) (PLA) scaffolds to create a 3D model of colorectal adenocarcinoma. Specifically, the physico-mechanical and morphological properties of PCL and PLA electrospun fiber meshes collected at different drum velocities, i.e., 500 rpm, 1000 rpm and 2500 rpm, were assessed. Fiber size, mesh porosity, pore size distribution, water contact angle and tensile mechanical properties were investigated. Caco-2 cells were cultured on the produced PCL and PLA scaffolds for 7 days, demonstrating good cell viability and metabolic activity in all the scaffolds. A cross-analysis of the cell-scaffold interactions with morphological, mechanical and surface characterizations of the different electrospun fiber meshes was carried out, showing an opposite trend of cell metabolic activity in PLA and PCL scaffolds regardless of the fiber alignment, which increased in PLA and decreased in PCL. The best samples for Caco-2 cell culture were PCL500 (randomly oriented fibers) and PLA2500 (aligned fibers). Caco-2 cells had the highest metabolic activity in these scaffolds, with Young's moduli in the range of 8.6-21.9 MPa. PCL500 showed Young's modulus and strain at break close to those of the large intestine. Advancements in 3D in vitro models of colorectal adenocarcinoma could move forward the development of therapies for this cancer.
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Adenocarcinoma , Neoplasias Colorretais , Humanos , Engenharia Tecidual/métodos , Células CACO-2 , Recidiva Local de Neoplasia , Poliésteres , Alicerces TeciduaisRESUMO
Polyhydroxyalkanoates (PHAs) are a family of biopolyesters synthesized by various microorganisms. Due to their biocompatibility and biodegradation, PHAs have been proposed for biomedical applications, including tissue engineering scaffolds. Olive leaf extract (OLE) can be obtained from agri-food biowaste and is a source of polyphenols with remarkable antioxidant properties. This study aimed at incorporating OLE inside poly(hydroxybutyrate-co-hydroxyvalerate) (PHBHV) fibers via electrospinning to obtain bioactive bio-based blends that are useful in wound healing. PHBHV/OLE electrospun fibers with a size of 1.29 ± 0.34 µm were obtained. Fourier transform infrared chemical analysis showed a uniform surface distribution of hydrophilic -OH groups, confirming the presence of OLE in the electrospun fibers. The main OLE phenols were released from the fibers within 6 days. The biodegradation of the scaffolds in phosphate buffered saline was investigated, demonstrating an adequate stability in the presence of metalloproteinase 9 (MMP-9), an enzyme produced in chronic wounds. The scaffolds were preliminarily tested in vitro with HFFF2 fibroblasts and HaCaT keratinocytes, suggesting adequate cytocompatibility. PHBHV/OLE fiber meshes hold promising features for wound healing, including the treatment of ulcers, due to the long period of durability in an inflamed tissue environment and adequate cytocompatibility.
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Poli-Hidroxialcanoatos , Antioxidantes/farmacologia , Hidroxibutiratos/farmacologia , Metaloproteinase 9 da Matriz , Olea , Ácidos Pentanoicos , Fosfatos , Extratos Vegetais , Poliésteres/química , Poli-Hidroxialcanoatos/química , Polifenóis , Estudos Prospectivos , Engenharia Tecidual , Alicerces Teciduais/química , CicatrizaçãoRESUMO
In the perspective of producing a rigid renewable and environmentally friendly rigid packaging material, two comb-like copolymers of cellulose acetate (AC) and oligo(lactic acid) OLA, feeding different percentages of oligo(lactic acid) segments, were prepared by chemical synthesis in solvent or reactive extrusion in the melt, using a diepoxide as the coupling agent and were used as compatibilizers for poly(lactic acid)/plasticized cellulose acetate PLA/pAC blends. The blends were extruded at 230 °C or 197 °C and a similar compatibilizing behavior was observed for the different compatibilizers. The compatibilizer C1 containing 80 wt% of AC and 14 wt% of OLA resulted effective in compatibilization and it was easily obtained by reactive extrusion. Considering these results, different PLAX/pAC(100-X) compounds containing C1 as the compatibilizer were prepared by extrusion at 197 °C and tested in terms of their tensile and impact properties. Reference materials were the uncompatibilized corresponding blend (PLAX/pAC(100-X)) and the blend of PLA, at the same wt%, with C1. Significant increase in Young's modulus and tensile strength were observed in the compatibilized blends, in dependence of their morphologic features, suggesting the achievement of an improved interfacial adhesion thanks to the occurred compatibilization.
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Cosmetics has recently focused on biobased skin-compatible materials. Materials from natural sources can be used to produce more sustainable skin contact products with enhanced bioactivity. Surface functionalization using natural-based nano/microparticles is thus a subject of study, aimed at better understanding the skin compatibility of many biopolymers also deriving from biowaste. This research investigated electrospray as a method for surface modification of cellulose tissues with chitin nanofibrils (CNs) using two different sources-namely, vegetable (i.e., from fungi), and animal (from crustaceans)-and different solvent systems to obtain a biobased and skin-compatible product. The surface of cellulose tissues was uniformly decorated with electrosprayed CNs. Biological analysis revealed that all treated samples were suitable for skin applications since human dermal keratinocytes (i.e., HaCaT cells) successfully adhered to the processed tissues and were viable after being in contact with released substances in culture media. These results indicate that the use of solvents did not affect the final cytocompatibility due to their effective evaporation during the electrospray process. Such treatments did not also affect the characteristics of cellulose; in addition, they showed promising anti-inflammatory and indirect antimicrobial activity toward dermal keratinocytes in vitro. Specifically, cellulosic substrates decorated with nanochitins from shrimp showed strong immunomodulatory activity by first upregulating then downregulating the pro-inflammatory cytokines, whereas nanochitins from mushrooms displayed an overall anti-inflammatory activity via a slight decrement of the pro-inflammatory cytokines and increment of the anti-inflammatory marker. Electrospray could represent a green method for surface modification of sustainable and biofunctional skincare products.
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Agaricales/química , Celulose/farmacologia , Quitina/farmacologia , Cosméticos/farmacologia , Derme/metabolismo , Queratinócitos/metabolismo , Penaeidae/química , Animais , Linhagem Celular , Celulose/química , Quitina/química , Cosméticos/química , Humanos , NanoestruturasRESUMO
In recent years, in order to obtain improved mechanical, thermal, electrical and barrier/transport properties, aligned carbonaceous nanomaterials/polymer nanocomposite films have been receiving growing attention. Correspondingly, the edge oxidized graphene oxide (EOGO) nanoplatelets alignment influence on the structure of the polyethersulfone (PES) membrane films for potential applications in water treatment field has been investigated. Aligned GO/PES nanocomposite membrane films were prepared by non-solvent phase inversion technique after the starting sol phase was preliminarily exposed to high electric fields (50 kV m-1). Either AC (100, 1000 Hz) or DC mode electric fields were alternatively employed, and the results from both vertical and horizontal field configurations were investigated for structural and morphological comparison. Both XRD, FTIR-ATR, EIS, SEM, TEM and tensile strength analyses were applied in order to characterize the films. The microscopic analyses results have demonstrated successful GO/PES nanocomposite formation and alignment of GO nanoplatelets with the field direction in the matrix at low to moderate (0.02-0.1% wt) GO loadings where the flakes were dispersed and exfoliated sufficiently. However, at higher loading levels (1 and 2% wt) the nanoplateles were mostly agglomerated and the big flakes consisting of irregular plates could not orient their axis parallel to the electric field at the employed field strengths. The results suggest a more effective role of higher frequencies (1000 Hz versus 100 Hz) electric field for alignment of GO nanoplatelets. Simple tensile tests have also similarly confirmed GO alignment under the electric fields at both low (0.1% wt) and moderately high (0.5% wt) GO contents. The tensile strength improvement of the horizontal field processed PES/GO nanocomposite up to 24% compared to its vertical field processed counterpart could be accounted as a proof of the successful alignment of the nanoplatelets. However, EIS results unveiled that non-solvent phase inversion casting method, in its general form, may not be a suitable method for producing materials with tailored properties, due to its random and uncontrollable pore forming mechanism.
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The use of biopolyesters, as polymeric matrices, and natural fillers derived from wastes or by-products of food production to achieve biocomposites is nowadays a reality. The present paper aims to valorize mussel shells, 95% made of calcium carbonate (CaCO3), converting them into high-value added products. The objective of this work was to verify if CaCO3, obtained from Mediterranean Sea mussel shells, can be used as filler for a compostable matrix made of Polylactic acid (PLA) and Poly(butylene adipate-co-terephthalate) (PBAT). Thermal, mechanical, morphological and physical properties of these biocomposites were evaluated, and the micromechanical mechanism controlling stiffness and strength was investigated by analytical predictive models. The performances of these biocomposites were comparable with those of biocomposites produced with standard calcium carbonate. Thus, the present study has proved that the utilization of a waste, such as mussel shell, can become a resource for biocomposites production, and can be an effective option for further industrial scale-up.
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Exoesqueleto/química , Bivalves/química , Poliésteres/química , Animais , PósRESUMO
In this paper the production of biopolymeric blends of poly(butylene succinate) PBS and plasticized whey protein (PWP), obtained from a natural by-product from cheese manufacturing, has been investigated for the production of films and/or sheets. In order to add the highest possible whey protein content, different formulations (from 30 to 50 wt.%) were studied. It was found that by increasing the amount of PWP added to PBS, the mechanical properties were worsened accordingly. This trend was attributed to the low compatibility between PWP and PBS. Consequently, the effect of the addition of soy lecithin and glycerol monostearate (GMS) as compatibilizers was investigated and compared to the use of whey protein modified with oleate and laurate groups obtained by Schotten-Baumann reaction. Soy lecithin and the Schotten-Baumann modified whey were effective in compatibilizing the PWP/PBS blend. In fact, a significant increase in elastic modulus, tensile strength and elongation at break with respect to the not compatibilized blend was observed and the length of aliphatic chains as well as the degree of modification of the Schotten-Baumann proteins affected the results. Moreover, thanks to DSC investigations, these compatibilizers were also found effective in increasing the PBS crystallinity.
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Butileno Glicóis/química , Polímeros/química , Proteínas do Soro do Leite/química , Cristalização , Módulo de Elasticidade , Glicerol/química , Lauratos/química , Lecitinas/química , Ácido Oleico/química , Conformação Proteica , Resistência à TraçãoRESUMO
In this work, composites based on poly(3-hydroxybutyrate-3-hydroxyvalerate) (PHB-HV) and waste wood sawdust (SD) fibers, a byproduct of the wood industry, were produced by melt extrusion and characterized in terms of processability, thermal stability, morphology, and mechanical properties in order to discriminate the formulations suitable for injection molding. Given their application in agriculture and/or plant nursery, the biodegradability of the optimized composites was investigated under controlled composting conditions in accordance with standard methods (ASTM D5338-98 and ISO 20200-2004). The optimized PHB-HV/SD composites were used for the production of pots by injection molding and their performance was qualitatively monitored in a plant nursery and underground for 14 months. This study presents a sustainable option of valuation of wood factory residues and lowering the production cost of PHB-HV-based compounds without affecting their mechanical properties, improving their impact resistance and biodegradability rates in terrestrial environments.
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Materiais Biocompatíveis/síntese química , Hidroxibutiratos/química , Poliésteres/síntese química , Madeira/química , Materiais Biocompatíveis/química , Biodegradação Ambiental , Poeira , Resíduos Industriais , Poliésteres/química , Termodinâmica , TermogravimetriaRESUMO
The circular economy policy and the interest for sustainable material are inducing a constant expansion of the bio-composites market. The opportunity of using natural fibers in bio-based and biodegradable polymeric matrices, derived from industrial and/or agricultural waste, represents a stimulating challenge in the replacement of traditional composites based on fossil sources. The coupling of bioplastics with natural fibers in order to lower costs and promote degradability is one of the primary objectives of research, above all in the packaging and agricultural sectors where large amounts of non-recyclable plastics are generated, inducing a serious problem for plastic disposal and potential accumulation in the environment. Among biopolymers, poly(lactic acid) (PLA) is one of the most used compostable, bio-based polymeric matrices, since it exhibits process ability and mechanical properties compatible with a wide range of applications. In this study, two types of cellulosic fibers were processed with PLA in order to obtain bio-composites with different percentages of microfibers (5%, 10%, 20%). The mechanical properties were evaluated (tensile and impact test), and analytical models were applied in order to estimate the adhesion between matrix and fibers and to predict the material's stiffness. Understanding these properties is of particular importance in order to be able to tune and project the final characteristics of bio-composites.
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Materiais Biocompatíveis/química , Celulose/química , Teste de Materiais/métodos , Poliésteres/química , Celulose/ultraestrutura , Módulo de Elasticidade , TermogravimetriaRESUMO
Chitin-nanofibrils are obtained in water suspension at low concentration, as nanoparticles normally are, to avoid their aggregation. The addition of the fibrils in molten PLA during extrusion is thus difficult and disadvantageous. In the present paper, the use of poly(ethylene glycol) (PEG) is proposed to prepare a solid pre-composite by water evaporation. The pre-composite is then added to PLA in the extruder to obtain transparent nanocomposites. The amount of PEG and chitin nanofibrils was varied in the nanocomposites to compare the reinforcement due to nanofibrils and plasticization due to the presence of PEG, as well as for extrapolating, where possible, the properties of reinforcement due to chitin nanofibrils exclusively. Thermal and morphological properties of nanocomposites were also investigated. This study concluded that chitin nanofibrils, added as reinforcing filler up to 12% by weight, do not properties alter the properties of the PLA based material; hence, this additive can be used in bioplastic items mainly exploiting their intrinsic anti-microbial and skin regenerating properties.
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Quitina/análogos & derivados , Nanocompostos/química , Nanofibras/química , Poliésteres/química , Temperatura Alta , Polietilenoglicóis/química , Resistência à TraçãoRESUMO
Chitin and lignin, by-products of fishery and plant biomass, can be converted to innovative high value bio- and eco-compatible materials. On the nanoscale, high antibacterial, anti-inflammatory, cicatrizing and anti-aging activity is obtained by controlling their crystalline structure and purity. Moreover, electropositive chitin nanofibrlis (CN) can be combined with electronegative nanolignin (NL) leading to microcapsule-like systems suitable for entrapping both hydrophilic and lipophilic molecules. The aim of this study was to provide morphological, physico-chemical, thermogravimetric and biological characterization of CN, NL, and CN-NL complexes, which were also loaded with glycyrrhetinic acid (GA) as a model of a bioactive molecule. CN-NL and CN-NL/GA were thermally stable up to 114 °C and 127 °C, respectively. The compounds were administered to in vitro cultures of human keratinocytes (HaCaT cells) and human mesenchymal stromal cells (hMSCs) for potential use in skin contact applications. Cell viability, cytokine expression and effects on hMSC multipotency were studied. For each component, CN, NL, CN-NL and CN-NL/GA, non-toxic concentrations towards HaCaT cells were identified. In the keratinocyte model, the proinflammatory cytokines IL-1α, IL-1 ß, IL-6, IL-8 and TNF-α that resulted were downregulated, whereas the antimicrobial peptide human ß defensin-2 was upregulated by CN-LN. The hMSCs were viable, and the use of these complexes did not modify the osteo-differentiation capability of these cells. The obtained findings demonstrate that these biocomponents are cytocompatible, show anti-inflammatory activity and may serve for the delivery of biomolecules for skin care and regeneration.
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Quitina/metabolismo , Lignina/metabolismo , Regeneração , Fenômenos Fisiológicos da Pele , Pele/metabolismo , Diferenciação Celular , Sobrevivência Celular , Quitina/química , Humanos , Lignina/química , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Nanoestruturas/ultraestrutura , Pele/citologia , Relação Estrutura-AtividadeRESUMO
The objective of this study was the preparation and physico-chemical, mechanical, biological, and functional characterization of a multifunctional coating for an innovative, fully implantable device. The multifunctional coating was designed to have three fundamental properties: adhesion to device, close mechanical resemblance to human soft tissues, and control of the inflammatory response and tissue repair process. This aim was fulfilled by preparing a multilayered coating based on three components: a hydrophilic primer to allow device adhesion, a poly(vinyl alcohol) hydrogel layer to provide good mechanical compliance with the human tissue, and a layer of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) fibers. The use of biopolymer fibers offered the potential for a long-term interface able to modulate the release of an anti-inflammatory drug (dexamethasone), thus contrasting acute and chronic inflammation response following device implantation. Two copolymers, poly(vinyl acetate-acrylic acid) and poly(vinyl alcohol-acrylic acid), were synthetized and characterized using thermal analysis (DSC, TGA), Fourier transform infrared spectroscopy (FT-IR chemical imaging), in vitro cell viability, and an adhesion test. The resulting hydrogels were biocompatible, biostable, mechanically compatible with soft tissues, and able to incorporate and release the drug. Finally, the multifunctional coating showed a good adhesion to titanium substrate, no in vitro cytotoxicity, and a prolonged and controlled drug release.
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Materiais Revestidos Biocompatíveis/química , Próteses e Implantes , Fenômenos Químicos , Técnicas de Química Sintética , Humanos , Hidrogéis/química , Fenômenos Mecânicos , TermodinâmicaRESUMO
The thermal, mechanical, and rheological properties of biocomposites of poly(lactic acid) (PLA) with potato pulp powder were investigated in order to (1) quantify how the addition of this filler modifies the structure of the polymeric material and (2) to obtain information on the possible miscibility and compatibility between PLA and the potato pulp. The potato pulp powder utilized is a residue of the processing for the production and extraction of starch. The study was conducted by analyzing the effect of the potato pulp concentration on the thermal, mechanical, and rheological properties of the biocomposites. The results showed that the potato pulp powder does not act as reinforcement but as filler for the PLA polymeric matrix. A progressive decrease in elastic modulus, tensile strength, and elongation at break was observed with increasing the potato pulp percentage. This moderate loss of mechanical properties, however, still meets the technical requirements indicated for the production of rigid packaging items. The incorporation of potato pulp powder to PLA offers the possibility to reduce the cost of the final products and promotes a circular economy approach for the valorization of agro-food waste biomass.
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Materiais Biocompatíveis/química , Poliésteres/química , Solanum tuberosum/química , Amido/química , Módulo de Elasticidade , Pós , Reologia , Temperatura , Resistência à TraçãoRESUMO
The intratumoral injection of cytokines, in particular IL2, has shown promise for cutaneous melanoma patients with unresectable disease or continuous recurrence despite surgery. We recently reported that the intralesional injection of L19-IL2, an immunocytokine combining IL2 and the human monoclonal antibody fragment L19, resulted in efficient regional control of disease progression, increased time to distant metastasis and evidence of effect on circulating immune cell populations. We have also shown in preclinical models of cancer a remarkable synergistic effect of the combination of L19-IL2 with L19-TNF, a second clinical-stage immunocytokine, based on the same L19 antibody fused to TNF. Here, we describe the results of a phase II clinical trial based on the intralesional administration of L19-IL2 and L19-TNF in patients with stage IIIC and IVM1a metastatic melanoma, who were not candidate to surgery. In 20 efficacy-evaluable patients, 32 melanoma lesions exhibited complete responses upon intralesional administration of the two products, with mild side effects mainly limited to injection site reactions. Importantly, we observed complete responses in 7/13 (53.8 %) non-injected lesions (4 cutaneous, 3 lymph nodes), indicating a systemic activity of the intralesional immunostimulatory treatment. The intralesional administration of L19-IL2 and L19-TNF represents a simple and effective method for the local control of inoperable melanoma lesions, with a potential to eradicate them or make them suitable for a facile surgical removal of the residual mass.
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Imunoterapia/métodos , Melanoma/terapia , Proteínas Recombinantes de Fusão/administração & dosagem , Neoplasias Cutâneas/terapia , Adulto , Idoso , Intervalo Livre de Doença , Sinergismo Farmacológico , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Injeções Intralesionais , Masculino , Melanoma/imunologia , Melanoma/mortalidade , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Estudos Prospectivos , Proteínas Recombinantes de Fusão/efeitos adversos , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/mortalidade , Adulto JovemRESUMO
The synergistic effect of nucleating agents and plasticizers on the thermal and mechanical performance of PLA nanocomposites was investigated with the objective of increasing the crystallinity and balancing the stiffness and toughness of PLA mechanical properties. Calcium carbonate, halloysite nanotubes, talc and LAK (sulfates) were compared with each other as heterogeneous nucleating agents. Both the DSC isothermal and non-isothermal studies indicated that talc and LAK were the more effective nucleating agents among the selected fillers. Poly(D-lactic acid) (PDLA) acted also as a nucleating agent due to the formation of the PLA stereocomplex. The half crystallization time was reduced by the addition of talc to about 2 min from 37.5 min of pure PLA by the isothermal crystallization study. The dynamic mechanical thermal study (DMTA) indicated that nanofillers acted as both reinforcement fillers and nucleating agents in relation to the higher storage modulus. The plasticized PLA studied by DMTA indicated a decreasing glass transition temperature with the increasing of the PEG content. The addition of nanofiller increased the Young's modulus. PEG had the plasticization effect of increasing the break deformation, while sharply decreasing the stiffness and strength of PLA. The synergistic effect of nanofillers and plasticizer achieved the balance between stiffness and toughness with well-controlled crystallization.
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Ácido Láctico/química , Plastificantes/química , Polímeros/química , Varredura Diferencial de Calorimetria , Cristalização , Poliésteres , TemperaturaRESUMO
In this study, we develop a bio-based and bioactive nanofibrous patch based on bacterial cellulose (BC) and chitin nanofibrils (CNs) using an ionic liquid as a solvent for BC, aimed at tympanic membrane (TM) repair. Electrospun BC nanofiber meshes were produced via electrospinning, and surface-modified with CNs using electrospray. The rheology of the BC/ionic liquid system was investigated. The obtained CN/BC meshes underwent comprehensive morphological, physicochemical, and mechanical characterization. Cytotoxicity tests were conducted using L929 mouse fibroblasts, revealing a cell viability of 97.8%. In vivo tests on rabbit skin demonstrated that the patches were nonirritating. Furthermore, the CN/BC fiber meshes were tested in vitro using human dermal keratinocytes (HaCaT cells) and human umbilical vein endothelial cells as model cells for TM perforation healing. Both cell types demonstrated successful growth on these scaffolds. The presence of CNs resulted in improved indirect antimicrobial activity of the electrospun fiber meshes. HaCaT cells exhibited an upregulated mRNA expression at 6 and 24 h of key proinflammatory cytokines crucial for the wound healing process, indicating the potential benefits of CNs in the healing response. Overall, this study presents a natural and eco-sustainable fiber mesh with great promise for applications in TM repair, leveraging the synergistic effects of BC and CNs to possibly enhance tissue regeneration and healing. Impact statement Repair of tympanic membrane perforations following chronic otitis media is a main clinical issue in otologic surgery, where the underlying infection obstacles self-healing. To address this challenge, our study proposes a bio-based patch made of nanoscale carbohydrate materials (i.e., bacterial cellulose electrospun fibers and chitin nanofibrils) processed via green solvents. The scaffold is nonirritating in vivo, and cytocompatible with fibroblasts, endothelial cells, and keratinocytes. In epithelial cells, it stimulates the expression of the antimicrobial peptide human beta defensin 2, with a pathway of cytokine expression compatible with the wound healing process. Therefore, it could be applied with unsolved infective pathology.
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Líquidos Iônicos , Nanofibras , Perfuração da Membrana Timpânica , Camundongos , Animais , Humanos , Coelhos , Celulose/farmacologia , Membrana Timpânica , Quitina/farmacologia , Células Endoteliais , Nanofibras/química , Alicerces Teciduais/químicaRESUMO
Currently, biobased epoxy resins derived from plant oils and natural fibers are available on the market and are a promising substitute for fossil-based products. The purpose of this work is to investigate novel lightweight thermoset fiber-reinforced composites with extremely high biobased content. Paying attention to the biobased content, following a cascade pathway, many trials were carried out with different types of resins and hardeners to select the best ones. The most promising formulations were then used to produce flax fiber reinforced composites by vacuum bagging process. The main biocomposite properties such as tensile, bending, and impact properties as well as the individuation of their glass transition temperatures (by DSC) were assessed. Three biocomposite systems were investigated with biobased content ranging from 60 to 91%, obtaining an elastic modulus that varied from 2.7 to 6.3 GPa, a flexural strength from 23 to 108.5 MPa, and Charpy impact strength from 11.9 to 12.2 kJ/m2. The properties reached by the new biocomposites are very encouraging; in fact, their stiffness vs. lightweight (calculated by the E/ρ3 ratio) is comparable to some typical epoxy-glass composites.
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More sustainable and smart cosmeceuticals and nutraceuticals are necessary due to the ecological transition. In this study, a pullulan-based water solution containing chitin nanofibril-nano-lignin (CN-LG) complexes that encapsulate fish collagen polypeptide, allantoin and nicotinamide was electrospun onto a nonwoven substrate made of bamboo fibers to obtain a smart nanostructured bilayer system for releasing active molecules onto the skin or other body tissues. Infrared spectroscopy was used to characterize the composition of the bilayer system before and after rapid washing of the sample with distilled water and liquids mimicking physiological fluids. The viability of keratinocytes was studied as well as the antioxidant activity, protective activity towards UV light, metalloproteinase release of aged fibroblasts and the inhibitor activity against collagen degradation. Immunomodulatory tests were performed to investigate the anti-inflammatory activity of the bilayer system as well as its indirect antimicrobial activity. The results indicate that the bilayer system can be used in the production of innovative sustainable cosmeceuticals. In general, the adopted strategy can be extended to several smart treatments for fast release that can be commercialized as solid products, thus avoiding the use of preservatives and water.
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Sustainable packaging has been steadily gaining prominence within the food industry, with biobased materials emerging as a promising substitute for conventional petroleum-derived plastics. This review is dedicated to the examination of innovative biobased materials in the context of bread packaging. It aims to furnish a comprehensive survey of recent discoveries, fundamental properties, and potential applications. Commencing with an examination of the challenges posed by various bread types and the imperative of extending shelf life, the review underscores the beneficial role of biopolymers as internal coatings or external layers in preserving product freshness while upholding structural integrity. Furthermore, the introduction of biocomposites, resulting from the amalgamation of biopolymers with active biomolecules, fortifies barrier properties, thus shielding bread from moisture, oxygen, and external influences. The review also addresses the associated challenges and opportunities in utilizing biobased materials for bread packaging, accentuating the ongoing requirement for research and innovation to create advanced materials that ensure product integrity while diminishing the environmental footprint.