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1.
ACS Appl Mater Interfaces ; 16(31): 41475-41486, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-38984990

RESUMO

The urgent challenges posed by the energy crisis, alongside the heat dissipation of advanced electronics, have embarked on a rising demand for the development of highly thermally conductive polymer composites. Electrospun composite mats, known for their flexibility, permeability, high concentration and orientational degree of conductive fillers, stand out as one of the prime candidates for addressing this need. This study explores the efficacy of boron nitride (BN) and its potential alternative, silicon nitride (SiN) nanoparticles, in enhancing the thermal performance of the electrospun composite thermoplastic polyurethane (TPU) fibers and mats. The 3D reconstructed models obtained from FIB-SEM imaging provided valuable insights into the morphology of the composite fibers, aiding the interpretation of the measured thermal performance through scanning thermal microscopy for the individual composite fibers and infrared thermography for the composite mats. Notably, we found that TPU-SiN fibers exhibit superior heat conduction compared to TPU-BN fibers, with up to a 6 °C higher surface temperature observed in mats coated on copper pipes. Our results underscore the crucial role of arrangement of nanoparticles and fiber morphology in improving heat conduction in the electrospun composites. Moreover, SiN nanoparticles are introduced as a more suitable filler for heat conduction enhancement of electrospun TPU fibers and mats, suggesting immense potential for smart textiles and thermal management applications.

2.
Int J Biol Macromol ; 275(Pt 1): 133602, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38964681

RESUMO

Various strategies have extensively explored enhancing the physical and biological properties of chitosan and cellulose scaffolds for skin tissue engineering. This study presents a straightforward method involving the addition of glycerol into highly porous structures of two polysaccharide complexes: chitosan/carboxymethyl cellulose (Chit/CMC) and chitosan/oxidized cellulose (Chit/OC); during a one-step freeze-drying process. Adding glycerol, especially to Chit/CMC, significantly increased stability, prevented degradation, and improved mechanical strength by nearly 50%. Importantly, after 21 days of incubation in enzymatic medium Chit/CMC scaffold has almost completely decomposed, while foams reinforced with glycerol exhibited only 40% mass loss. It is possible due to differences in multivalent cations and polymer chain contraction, resulting in varied hydrogen bonding and, consequently, distinct physicochemical outcomes. Additionally, the scaffolds with glycerol improved the cellular activities resulting in over 40% higher proliferation of fibroblast after 21 days of incubation. It was achieved by imparting water resistance to the highly absorbent material and aiding in achieving a balance between hydrophilic and hydrophobic properties. This study clearly indicates the possible elimination of additional crosslinkers and multiple fabrication steps that can reduce the cost of scaffold production for skin tissue engineering applications while tailoring mechanical strength and degradation.


Assuntos
Celulose , Quitosana , Liofilização , Glicerol , Pele , Engenharia Tecidual , Alicerces Teciduais , Engenharia Tecidual/métodos , Quitosana/química , Glicerol/química , Alicerces Teciduais/química , Celulose/química , Porosidade , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Materiais Biocompatíveis/química , Animais , Resistência à Tração , Fenômenos Mecânicos , Humanos
3.
ACS Appl Mater Interfaces ; 16(29): 37783-37794, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-38994590

RESUMO

Atopic skin is dry and itchy and lacks integrity. Impaired skin barrier results from altered lipid composition of the skin. A crucial skin lipid, cholesterol, provides flexibility and homeostasis of the cell membranes' lipid bilayer. Cholesterol-based creams and natural oils, especially blackcurrant seed oil, are beneficial for skin care as they hydrate the skin and improve its integrity. The major atopic symptom, skin dryness, can be overcome by the application of porous patches enhanced with cholesterol and natural oil. The base of the patches is constructed of polyimide (PI) nanofibers with cholesterol coatings and externally added blackcurrant seed oil. The presence of cholesterol in PI mats hinders the passage of oil through the patches to the skin, resulting in sustained and prolonged skin hydration. The theoretical and numerical investigations of oil dynamics in porous mats confirmed the experimental results, showing a prolonged skin hydration effect up to 6 h. Additionally, as demonstrated by in vivo tests on atopic mice, cholesterol patches lower serum immunoglobulin E levels and expression of proinflammatory cytokines in the skin, thereby accelerating skin healing. Our results hold great promise for the long-term application of the patches in atopic dermatitis treatment.


Assuntos
Colesterol , Dermatite Atópica , Nanofibras , Pele , Colesterol/química , Nanofibras/química , Animais , Dermatite Atópica/tratamento farmacológico , Dermatite Atópica/patologia , Camundongos , Pele/efeitos dos fármacos , Pele/metabolismo , Pele/patologia , Inflamação/tratamento farmacológico , Óleos de Plantas/química , Óleos de Plantas/farmacologia , Humanos
4.
Adv Sci (Weinh) ; : e2404154, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38925613

RESUMO

The global climate change is mainly caused by carbon dioxide (CO2) emissions. To help reduce CO2 emissions and conserve thermal energy, sustainable materials based on flexible thermal insulation are developed to minimize heat flux, drawing inspiration from natural systems such as polar bear hairs. The unique structure of hollow double-shell fibers makes it possible to achieve low thermal conductivity in the material while retaining exceptional elasticity, allowing it to adapt to insulation systems of any shape. The layered system of porous mats reaches a thermal conductivity coefficient of 0.031 W∙m⁻¹âˆ™K⁻¹ and enables to reduce the heat transfer. The results achieved using scanning thermal microscopy (SThM) correlate with the simulated heat flow in the case of individual fibers. This research study brings new insights into the energy efficiency of domestic environments, thereby addressing the growing demand for sustainable and high-performance insulation materials for saving energy loss and reducing pollution footprint.

5.
Int J Mol Sci ; 25(9)2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38732199

RESUMO

Nanofibrous materials generated through electrospinning have gained significant attention in tissue regeneration, particularly in the domain of bone reconstruction. There is high interest in designing a material resembling bone tissue, and many scientists are trying to create materials applicable to bone tissue engineering with piezoelectricity similar to bone. One of the prospective candidates is highly piezoelectric poly(vinylidene fluoride) (PVDF), which was used for fibrous scaffold formation by electrospinning. In this study, we focused on the effect of PVDF molecular weight (180,000 g/mol and 530,000 g/mol) and process parameters, such as the rotational speed of the collector, applied voltage, and solution flow rate on the properties of the final scaffold. Fourier Transform Infrared Spectroscopy allows for determining the effect of molecular weight and processing parameters on the content of the electroactive phases. It can be concluded that the higher molecular weight of the PVDF and higher collector rotational speed increase nanofibers' diameter, electroactive phase content, and piezoelectric coefficient. Various electrospinning parameters showed changes in electroactive phase content with the maximum at the applied voltage of 22 kV and flow rate of 0.8 mL/h. Moreover, the cytocompatibility of the scaffolds was confirmed in the culture of human adipose-derived stromal cells with known potential for osteogenic differentiation. Based on the results obtained, it can be concluded that PVDF scaffolds may be taken into account as a tool in bone tissue engineering and are worth further investigation.


Assuntos
Nanofibras , Polivinil , Engenharia Tecidual , Alicerces Teciduais , Engenharia Tecidual/métodos , Polivinil/química , Humanos , Alicerces Teciduais/química , Nanofibras/química , Materiais Biocompatíveis/química , Células Cultivadas , Espectroscopia de Infravermelho com Transformada de Fourier , Diferenciação Celular/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Células Estromais/citologia , Células Estromais/metabolismo , Peso Molecular , Polímeros de Fluorcarboneto
6.
Colloids Surf B Biointerfaces ; 237: 113864, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38522283

RESUMO

Electrospun polymer scaffolds have gained prominence in biomedical applications, including tissue engineering, drug delivery, and wound dressings, due to their customizable properties. As the interplay between cells and materials assumes fundamental significance in biomaterials research, understanding the relationship between fiber properties and cell behaviour is imperative. Nevertheless, altering fiber properties introduces complexity by intertwining mechanical and surface chemistry effects, challenging the differentiation of their individual impacts on cell behaviour. Core-shell fibers present an appealing solution, enabling the control of mechanical properties of scaffolds, flexibility in material and drug selection, efficient encapsulation, strong protection of bioactive drugs against harsh environments, and controlled, prolonged drug release. This study addresses a key challenge in core-shell fiber design related to the blending effect between core and shell polymers. Two types of fibers, PMMA and core-shell PC-PMMA, were electrospun, and thorough analyses confirmed the desired core-shell structure in PC-PMMA fibers. Surface chemistry analysis revealed PC diffusion to the PMMA shell of the core-shell fiber during electrospinning, subsequently prompting an investigation of the fiber's surface potential. Conducting cellular studies on osteoblasts by super-resolution confocal microscopy provided insights into the direct influence of interfacial polymer blending and, consequently, altered fiber surface and mechanical properties on cell focal adhesion points, bridging the gap between material attributes and cell responses in core-shell fibers.


Assuntos
Polímeros , Polimetil Metacrilato , Polímeros/química , Polimetil Metacrilato/química , Adesões Focais , Engenharia Tecidual , Materiais Biocompatíveis/química , Alicerces Teciduais/química
7.
ACS Appl Mater Interfaces ; 16(8): 9944-9955, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38354103

RESUMO

The complex interplay between cells and materials is a key focus of this research, aiming to develop optimal scaffolds for regenerative medicine. The need for tissue regeneration underscores understanding cellular behavior on scaffolds, especially cell adhesion to polymer fibers forming focal adhesions. Key proteins, paxillin and vinculin, regulate cell signaling, migration, and mechanotransduction in response to the extracellular environment. This study utilizes advanced microscopy, specifically the AiryScan technique, along with advanced image analysis employing the Density-Based Spatial Clustering of Applications with Noise (DBSCAN) cluster algorithm, to investigate protein distribution during osteoblast cell adhesion to polymer fibers and glass substrates. During cell attachment to both glass and polymer fibers, a noticeable shift in the local maxima of paxillin and vinculin signals is observed at the adhesion sites. The focal adhesion sites on polymer fibers are smaller and elliptical but exhibit higher protein density than on the typical glass surface. The characteristics of focal adhesions, influenced by paxillin and vinculin, such as size and density, can potentially reflect the strength and stability of cell adhesion. Efficient adhesion correlates with well-organized, larger focal adhesions characterized by increased accumulation of paxillin and vinculin. These findings offer promising implications for enhancing scaffold design, evaluating adhesion to various substrates, and refining cellular interactions in biomedical applications.


Assuntos
Adesões Focais , Mecanotransdução Celular , Paxilina/metabolismo , Vinculina/metabolismo , Adesões Focais/metabolismo , Adesão Celular/fisiologia , Polímeros/metabolismo , Fosfoproteínas/metabolismo , Proteína-Tirosina Quinases de Adesão Focal/metabolismo
8.
ACS Appl Mater Interfaces ; 15(48): 56575-56586, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37985370

RESUMO

The ever-increasing demand for self-powered systems such as glucose biosensors and mixed reality devices has sparked significant interest in triboelectric generators, which hold large potential as renewable energy solutions. Our study explores new methods for integrating energy-harvesting capabilities into smart textiles by developing strong and efficient yarns that can convert mechanical energy into electrical energy through a triboelectric effect. Specifically, we focused on Nylon-11 (PA11), a material known for its crystalline structure well-suited for generating a powerful triboelectric response. To achieve this, we created triboelectric yarns by electrospinning PA11 fibers onto conductive carbon yarns, enabling energy-harvesting applications. Extensive testing demonstrated that these yarns possess exceptional durability, surpassing real-life usage requirements while experiencing minimal degradation. Additionally, we developed a prototype haptic device by interweaving tribopositive PA11 and tribonegative poly(vinylidene fluoride) (PVDF) triboelectric yarns. Our research has successfully yielded durable and efficient yarns with strong energy-harvesting capabilities, opening up possibilities for integrating smart textiles into practical scenarios. These technologies are promising steps to achieve greener and more reliable self-powered systems.

9.
ACS Appl Mater Interfaces ; 15(33): 40001-40010, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37556848

RESUMO

The global water supply worsens yearly with climate change; therefore, the need for sustainable water resources is growing. One of them is fog water collectors with variable surface wettability, with multifunctional designs for utilization worldwide and to address regions with low humidity levels. Therefore, we created fiber meshes with a photoresponsive switchable surface. This study uses electrospun polyvinylidene fluoride (PVDF) meshes, whose wettability is controlled by adding TiO2. The fog water collection performance is studied at high and low humidity levels. With TiO2-PVDF, the electrospun mesh can be converted from hydrophobic to hydrophilic under UV irradiation and transformed back to a hydrophobic state with heat treatment. The switchable meshes were found to be more effective at water collection after UV irradiation at lower fog rates of 200 mL·h-1. The ability to switch between hydrophobic and hydrophilic properties as needed is highly desired in fog collection applications using electrospun meshes, as it can improve overall efficiency after UV irradiation.

10.
Small ; 19(52): e2305104, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37553775

RESUMO

The pressing issues of the energy crisis and rapid electronics development have sparked a growing interest in the production of highly thermally conductive polymer composites. Due to the challenges related to the poor processability of hybrid materials and filler distribution to achieve high thermal conductivity, electrospinning is employed to create composite nanofibers and yarns using polyimide (PI) and thermally conductive silicon nitride (SiN) nanoparticles. The thermal performance of the individual nanofibers is evaluated using scanning thermal microscopy (SThM), providing significant insights into their heat transfer performance. Next, the nanofibers are applied as coatings on resistance wires to assess the thermal conductivity and insulation properties. Notably, the samples containing 35 wt.% of SiN exhibit a 25% increase in surface temperature. These innovative materials hold great promise as exceptional candidates for smart textiles and thermal management applications, addressing the growing demand for effective heat dissipation and regulation.

11.
Biomater Adv ; 151: 213429, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37148597

RESUMO

The loss of the myelin sheath insulating axons is the hallmark of demyelinating diseases. These pathologies often lead to irreversible neurological impairment and patient disability. No effective therapies are currently available to promote remyelination. Several elements contribute to the inadequacy of remyelination, thus understanding the intricacies of the cellular and signaling microenvironment of the remyelination niche might help us to devise better strategies to enhance remyelination. Here, using a new in vitro rapid myelinating artificial axon system based on engineered microfibres, we investigated how reactive astrocytes influence oligodendrocyte (OL) differentiation and myelination ability. This artificial axon culture system enables the effective uncoupling of molecular cues from the biophysical properties of the axons, allowing the detailed study of the astrocyte-OL crosstalk. Oligodendrocyte precursor cells (OPCs) were cultured on poly(trimethylene carbonate-co-ε-caprolactone) copolymer electrospun microfibres that served as surrogate axons. This platform was then combined with a previously established tissue engineered glial scar model of astrocytes embedded in 1 % (w/v) alginate matrices, in which astrocyte reactive phenotype was acquired using meningeal fibroblast conditioned medium. OPCs were shown to adhere to uncoated engineered microfibres and differentiate into myelinating OL. Reactive astrocytes were found to significantly impair OL differentiation ability, after six and eight days in a co-culture system. Differentiation impairment was seen to be correlated with astrocytic miRNA release through exosomes. We found significantly reduction on the expression of pro-myelinating miRNAs (miR-219 and miR-338) and an increase in anti-myelinating miRNA (miR-125a-3p) content between reactive and quiescent astrocytes. Additionally, we show that OPC differentiation inhibition could be reverted by rescuing the activated astrocytic phenotype with ibuprofen, a chemical inhibitor of the small rhoGTPase RhoA. Overall, these findings show that modulating astrocytic function might be an interesting therapeutic avenue for demyelinating diseases. The use of these engineered microfibres as an artificial axon culture system will enable the screening for potential therapeutic agents that promote OL differentiation and myelination while providing valuable insight on the myelination/remyelination processes.


Assuntos
Doenças Desmielinizantes , MicroRNAs , Remielinização , Humanos , Astrócitos/metabolismo , Astrócitos/patologia , Remielinização/fisiologia , Oligodendroglia/metabolismo , Oligodendroglia/patologia , Doenças Desmielinizantes/metabolismo , Doenças Desmielinizantes/patologia
12.
Nanoscale ; 15(15): 6890-6900, 2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-36960764

RESUMO

The medical field is continuously seeking new solutions and materials, where cellulose materials due to their high biocompatibility have great potential. Here we investigate the applicability of cellulose acetate (CA) electrospun fibers for bone tissue regeneration. For the first time we show the piezoelectric properties of electrospun CA fibers via high voltage switching spectroscopy piezoresponse force microscopy (HVSS-PFM) tests, which are followed by surface potential studies using Kelvin probe force microscopy (KPFM) and zeta potential measurements. Piezoelectric coefficient for CA fibers of 6.68 ± 1.70 pmV-1 along with high surface (718 mV) and zeta (-12.2 mV) potentials allowed us to mimic natural electrical environment favoring bone cell attachment and growth. Importantly, the synergy between increased surface potential and highly developed structure of the fibrous scaffold led to the formation of a vast 3D network of collagen produced by osteoblasts only after 7 days of in vitro culture. We clearly show the advantages of CA scaffolds as a bone replacement material, when long-lasting structural support is needed.


Assuntos
Engenharia Tecidual , Alicerces Teciduais , Alicerces Teciduais/química , Osteoblastos , Celulose/farmacologia , Celulose/química , Colágeno/química
13.
Carbohydr Polym ; 301(Pt A): 120277, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36436848

RESUMO

Chitosan-based films modified with synthesized (propylene glycol monoacetate, propylene glycol esters of fatty acids, and epoxidized propylene glycol esters) and commercial eco-friendly plasticizers (epoxidized soybean oil and epoxidized palm oil) were prepared by a casting technique, with the aim to obtain environmentally friendly materials for packaging applications. To assess the applicability of alternative plasticizers, their properties were compared to the two most common plasticizers, i.e. glycerol and sorbitol. The chemical structure of newly synthesized plasticizers was verified by gas chromatography with mass detector, infrared spectroscopy and 1H NMR; and their acid, epoxy, iodine, and saponification values were determined. Plasticized chitosan-based films were characterized in terms of hydrophilic, barrier, thermal, mechanical properties, zeta potential and morphology, confirming their flexibility and homogeneity. The research confirmed that the alternative plasticizers introduced by us are more effective than commercially available ones, exhibiting lower hydrophilicity and superior mechanical properties compared to samples plasticized with traditional plasticizers. Moreover, these properties were found to be even better after ageing for 10 months.


Assuntos
Quitosana , Plastificantes , Plastificantes/química , Quitosana/química , Glicerol/química , Ésteres , Propilenoglicóis
14.
Artigo em Inglês | MEDLINE | ID: mdl-35817463

RESUMO

The skin is a complex layer system and the most important barrier between the environment and the organism. In this review, we describe some widespread skin problems, with a focus on eczema, which are affecting more and more people all over the world. Most of treatment methods for atopic dermatitis (AD) are focused on increasing skin moisture and protecting from bacterial infection and external irritation. Topical and transdermal treatments have specific requirements for drug delivery. Breathability, flexibility, good mechanical properties, biocompatibility, and efficacy are important for the patches used for skin. Up to today, electrospun fibers are mostly used for wound dressing. Their properties, however, meet the requirements for skin patches for the treatment of AD. Active agents can be incorporated into fibers by blending, coaxial or side-by-side electrospinning, and also by physical absorption post-processing. Drug release from the electrospun membranes is affected by drug and polymer properties and the technique used to combine them into the patch. We describe in detail the in vitro release mechanisms, parameters affecting the drug transport, and their kinetics, including theoretical approaches. In addition, we present the current research on skin patch design. This review summarizes the current extensive know-how on electrospun fibers as skin drug delivery systems, while underlining the advantages in their prospective use as patches for atopic dermatitis. This article is categorized under: Implantable Materials and Surgical Technologies > Nanomaterials and Implants Implantable Materials and Surgical Technologies > Nanotechnology in Tissue Repair and Replacement Therapeutic Approaches and Drug Discovery > Emerging Technologies.


Assuntos
Dermatite Atópica , Humanos , Dermatite Atópica/tratamento farmacológico , Pele , Sistemas de Liberação de Medicamentos , Cicatrização , Bandagens
15.
Polymers (Basel) ; 14(22)2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36433170

RESUMO

With the increasing demand for smart textile and sensor applications, the interest in printed electronics is rising. In this study, we explore the applicability of electrospun membranes, characterized by high porosity and hydrophobicity, as potential substrates for printed electronics. The two most common inks, silver and carbon, were used in inkjet printing to create a conductive paths on electrospun membranes. As substrates, we selected hydrophobic polymers, such as polyimide (PI), low- and high-molecular-weight poly (vinyl butyral-co-vinyl alcohol-co-vinyl acetate) (PVB) and polystyrene (PS). Electrospinning of PI and PVB resulted in nanofibers in the range of 300-500 nm and PVB and PS microfibers (1-5 µm). The printed patterns were investigated with a scanning electron microscope (SEM) and resistance measurements. To verify the biocompatibility of printed electrodes on the membranes, an indirect cytotoxicity test with cells (MG-63) was performed. In this research, we demonstrated good printability of silver and carbon inks on flexible PI, PVB and PS electrospun membranes, leading to electrodes with excellent conductivity. The cytotoxicity study indicated the possibility of using manufactured printed electronics for various sensors and also as topical wearable devices.

16.
Biomater Adv ; 136: 212786, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35929319

RESUMO

With the increasing number of skin problems such as atopic dermatitis and the number of affected people, scientists are looking for alternative treatments to standard ointment or cream applications. Electrospun membranes are known for their high porosity and surface to volume area, which leads to a great loading capacity and their applications as skin patches. Polymer fibers are widely used for biomedical applications such as drug delivery systems or regenerative medicine. Importantly, fibrous meshes are used as oil reservoirs due to their excellent absorption properties. In our study, nano- and microfibers of poly (vinyl butyral-co-vinyl alcohol-co-vinyl acetate) (PVB) were electrospun. The biocompatibility of PVB fibers was confirmed with the keratinocytes culture studies, including cells' proliferation and replication tests. To verify the usability and stretchability of electrospun membranes, they were tested in two forms as-spun and elongated after uniaxially stretched. We examine oil transport through the patches for as-spun fibers and compare it with the numerical simulation of oil flow in the 3D reconstruction of nano- and microfiber networks. Evening primrose oil spreading and water vapor transmission rate (WVTR) tests were performed too. Finally, for skin hydration tests, manufactured materials loaded with evening primrose oil were applied to the forearm of volunteers for 6 h, showing increased skin moisture after using patches. This study clearly demonstrates that pore size and shape, together with fiber diameter, influence oil transport in the electrospun patches allowing to understand the key driving process of electrospun PVB patches for skin hydration applications. The oil release improves skin moisture and can be designed regarding the needs, by manufacturing different fibers' sizes and arrangements. The fibrous based patches loaded with oils are easy to handle and could remain on the altered skin for a long time and deliver the oil, therefore they are an ideal material for overnight bandages for skin treatment.


Assuntos
Ácidos Linoleicos , Ácido gama-Linolênico , Administração Cutânea , Humanos , Oenothera biennis , Óleos de Plantas
17.
Pharmaceutics ; 14(7)2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35890388

RESUMO

Skin diseases such as atopic dermatitis (AD) are widespread and affect people all over the world. Current treatments for dry and itchy skin are mostly focused on pharmaceutical solutions, while supportive therapies such as ointments bring immediate relief. Electrospun membranes are commonly used as a drug delivery system, as they have a high surface to volume area, resulting in high loading capacity. Within this study we present the manufacturing strategies of skin patches using polymer membranes with active substances for treating various skin problems. Here, we manufactured the skin patches using electrospun poly(vinyl butyral-co-vinyl alcohol-co-vinyl acetate) (PVB) fibers blended and electrosprayed with urea. The highest cumulative release of urea was obtained from the PVB patches manufactured via blend electrospinning with 5% of the urea incorporated in the fiber. The maximum concentration of released urea was acquired after 30 min, which was followed up by 6 h of constant release level. The simultaneous electrospinning and electrospraying limited the urea deposition and resulted in the lowest urea incorporation followed by the low release level. The urea-based patches, manufactured via blend electrospinning, exhibited a great potential as overnight treatment for various skin problems and their development can bring new trends to the textile-based therapies for AD.

18.
J Mater Chem B ; 10(11): 1763-1774, 2022 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-35254375

RESUMO

The growing problem of skin diseases due to allergies often causing atopic dermatitis, which is characterized by itching, burning, and redness, constantly motivates researchers to look for solutions to soothe these effects by moisturizing skin properly. For this purpose, we combined poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) electrospun fibers with evening primrose oil (EPO) into a system of patches to ensure skin hydration. Moreover, the dressing or patch application requires appropriate stretchability and wettability of the electrospun material. Thus, we examined the mechanical properties of the PHBV blend with EPO, as well as changes in wettability of the fiber surface depending on the share of EPO additive in the blend. The effectiveness of the patches has been characterized using the water vapor transmission rate as well as by the skin moisturizing index. The thermal insulation effect of the patches on human skin has been verified as well. The patches made by combining the polymer with natural oil showed enhanced mechanical properties and increased skin hydration, indicating the potential applicability of PHBV-based patches. The presented discovery of PHBV patches with EPO is a prospective and alternative treatment for patients for whom current state-of-the-art methods do not bring satisfactory results.


Assuntos
Poliésteres , Ácido gama-Linolênico , Humanos , Ácidos Linoleicos , Oenothera biennis , Óleos de Plantas , Estudos Prospectivos , Pele , Molhabilidade
19.
Int J Mol Sci ; 23(2)2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35055172

RESUMO

Reduced graphene oxide (rGO) is one of the graphene derivatives that can be employed to engineer bioactive and/or electroactive scaffolds. However, the influence of its low and especially high concentrations on scaffolds' overall properties and cytotoxicity has yet to be explored. In this study, polyethylene oxide (PEO)-based scaffolds containing from 0.1 to 20 wt% rGO were obtained by electrospinning. Morphological, thermal and electrical properties of the scaffolds were characterized by SEM, Raman spectroscopy, XRD, DSC and electrical measurements. The diameter of the fibers decreased from 0.52 to 0.19 µm as the concentration of rGO increased from 0.1 wt% to 20 wt%. The presence of rGO above the percolation threshold (5.7 wt%) resulted in a significantly reduced electrical resistivity of the scaffolds. XRD and Raman analysis revealed delamination of the graphene layers (interlayer spacing increased from 0.36 nm to 0.40-0.41 nm), and exfoliation of rGO was detected for the samples with an rGO concentration lower than 1 wt%. In addition, an evident trend of increasing cell viability as a function of the rGO concentration was evidenced. The obtained results can serve as further guidance for the judicious selection of the rGO content incorporated into the PEO matrix for constructing electroactive scaffolds.


Assuntos
Grafite/química , Polietilenoglicóis/química , Alicerces Teciduais/química , Linhagem Celular , Sobrevivência Celular , Humanos , Análise Espectral Raman , Engenharia Tecidual , Difração de Raios X
20.
ACS Biomater Sci Eng ; 7(12): 5339-5362, 2021 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-34649426

RESUMO

Biodegradable polymeric biomaterials offer a significant advantage in disposable or fast-consuming products in medical applications. Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is an example of a polyhydroxyalkanoate (PHA), i.e., one group of natural polyesters that are byproducts of reactions taking place in microorganisms in conditions with an excess carbon source. PHA polymers are a promising material for the production of everyday materials and biomedical applications. Due to the high number of monomers in the group, PHAs permit modifications enabling the production of copolymers of different compositions and with different proportions of individual monomers. In order to change and improve the properties of polymer fibers, PHAs are combined with either other natural and synthetic polymers or additives of inorganic phases. Importantly, electrospun PHBV fibers and mats showed an enormous potential in both the medical field (tissue engineering scaffolds, plasters, wound healing, drug delivery systems) and industrial applications (filter systems, food packaging). This Review summarizes the current state of the art in processing PHBV, especially by electrospinning, its degradation processes, and biocompatibility studies, starting from a general introduction to the PHA group of polymers.


Assuntos
Poli-Hidroxialcanoatos , Engenharia Tecidual , Materiais Biocompatíveis , Poliésteres , Alicerces Teciduais
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