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This paper explores the impact of encapsulation techniques on bioactive compounds, vitamins, and minerals, which are crucial for delivering bioactive compounds. Due to their instability and reactivity with the environment, encapsulation is often necessary to make these compounds suitable for medical or dietary applications. The evaluation of the kinetic model of bioactives reveals that encapsulation can significantly enhance their stability. However, encapsulation is not without its drawbacks. Incomplete encapsulation can reduce the effectiveness of the bioactives, and complexity of encapsulation processes can hinder widespread adoption. Interactions between the encapsulated materials and the encapsulating agents may also impact the release and bioavailability of the bioactives. It also presents perspectives for future research aimed at overcoming the limitations and enhancing the effectiveness of encapsulation. As research continues to advance, encapsulation is poised to play critical role in improving the delivery and stability of bioactive compounds, benefiting the food, pharmaceutical, and cosmetic industries.
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Levan is a fructose polysaccharide with multiple applications in different fields, but its obtaining in powdered form with a narrow particle size distribution is a complicated task. Two techniques, electrospraying and supercritical antisolvent (SAS) precipitation, were used to process levan that was first obtained enzymatically. The SAS process was able to micronize the polymer (at experimental conditions far above the mixture critical point of the solvent-antisolvent system) to obtain spherical particles between 0.30 and 0.50 µm with a proper particle size distribution. In this case, the Peng-Robinson equation of state was used to theoretically determine the mixture critical point. Bigger and elongated particles were obtained with electrospraying (0.60 µm). According to solution properties, mainly rheology, solubility and conductivity, the best solvent for levan electrospraying, in order to avoid problems of solvent evaporation and jet formation, was a mixture of water and ethanol with a polymer concentration of 50 mg·cm-3. Indeed, that solution has a viscous behavior (according to the oscillatory analysis), a low degree of pseudo-plasticity (based on the shear flow analysis), and the highest value of conductivity. Therefore, the particle size distribution of levan in powdered form can be tuned depending on the technique used.
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The incorporation of sensitive bioactive substances such as proteins or DNA into nanofibers poses a significant problem due to the toxicity of most organic solvents. The main idea of this study is to use alternating current electrospraying to create a suspension consisting of polyvinyl alcohol (PVA) capsules containing a bioactive substance dispersed in a solvent system suitable for a water-insoluble biocompatible polymer. In this suspension consisting of PVA capsules and a chloroform/ethanol mixture, poly (ε-caprolactone) (PCL) was dissolved and spun by needle-free electrospinning. The result is a fibrous PCL structure in which PVA capsules containing the bioactive agent are integrated. The PVA capsules protect the bioactive substance from the organic solvents needed to dissolve the PCL. To verify the efficacy of the capsules' protection against chloroform, the green fluorescent protein was first encapsulated into the nanofibers, followed by horseradish peroxidase. Both molecules were shown to retain their bioactivity within the nanofibers.
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Mesoporous silica particles (MSPs) have been investigated as potential carriers to increase the apparent solubility and dissolution rate of poorly water-soluble drugs by physically stabilising the amorphous nature of the loaded drug. In preparing such systems, it is recognized that the loading method has a critical impact on the physical state and performance of the drug. To date, there has been very limited investigation into the use of electrospraying for loading drugs into mesoporous silica. In this study, we further explore the use of this approach, in particular as a means of producing amorphous and high drug-loaded MSPs; the study includes an investigation of the effect of drug loading and MSP concentration on the formulation performance and process. A comparison with rotary evaporation, a more widely utilised loading technique, was conducted to assess the relative effectiveness of electrospraying. The physical state of the drug in the formulations was assessed using powder X-ray diffraction (PXRD) and differential scanning calorimetry (DSC). The drug release profiles were determined by a comparative in vitro drug release test. Electrospraying successfully produced formulations containing amorphous drug even at a high drug loading. In contrast, while itraconazole was present in amorphous form at the lower drug-loaded formulations produced by rotary evaporation, the drug was in the crystalline state at the higher loadings. The percentage of drug released was enhanced up to ten times compared to that of pure itraconazole for all the formulations apart from the highest loaded (crystalline) formulation prepared by rotary evaporation. Supersaturation for at least six hours was maintained by the formulations loaded with up to 30 mg/mL itraconazole produced by electrospraying. Overall, the results of this study demonstrate that electrospraying is capable of producing amorphous drug-loaded MSPs at high loadings, with associated favourable release characteristics. A comparison with the standard rotary evaporation approach indicates that electrospraying may be more effective for the production of higher loadings of amorphous material.
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Microalgae are increasingly playing a significant role in many areas of research and development. Recent studies have demonstrated their ability to aid wound healing by their ability to generate oxygen, aiding the healing process. Bearing this in mind, the capability to spray/spin deposit microalgae in suspension (solution) or compartmentalize living microalgae within architectures such as fibers/scaffolds and beads, would have significance as healing mechanisms for addressing a wide range of wounds. Reconstructing microalgae-bearing architectures as either scaffolds or beads could be generated via electric field (bio-electrospraying and cell electrospinning) and non-electric field (aerodynamically assisted bio-jetting/threading) driven technologies. However, before studying the biomechanical properties of the generated living architectures, the microalgae exposed to these techniques must be interrogated from a molecular level upward first, to establish these techniques, have no negative effects brought on the processed microalgae. Therefore these studies, demonstrate the ability of both these jetting and threading technologies to directly handle living microalgae, in suspension or within a polymeric suspension, safely, and form algae-bearing architectures such as beads and fibers/scaffolds.
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MicroalgasRESUMO
The focus of the present study is on the fabrication of effective and eco-friendly hybrid electrospun materials based on poly(L-lactide-co-D,L-lactide) (PLDLLA), Fe3O4 and ZnO with an appropriate design for antioxidant and photocatalytic performance. The design of the fibrous materials was purposely tailored in one step by electrospinning and simultaneous electrospinning/electrospraying. Electrospinning of PLDLLA and its mixture with Fe3O4 resulted in the fabrication of materials with design type "in". Furthermore, the surface of the electrospun PLDLLA and Fe3O4-in-PLDLLA was decorated with ZnO particles by simultaneous electrospraying, thus materials with design type "on" were obtained. In this case, quaternized N,N,N-trimethyl chitosan iodide (QCOS) was used as a sticking agent of ZnO particles onto the fiber's surface. Different structures and morphologies of the electrospun materials were observed by SEM equipped with EDX and TEM. TGA and XRD analyses show that the presence of inorganic particles had an impact on the thermal properties and crystallinity of the electrospun materials. Furthermore, the material type "on" showed improved wettability with a water contact angle less than 90° compared to the material type "in" with an angle larger than 90°. In particular, the presence of Fe3O4 imparts complementary magnetic properties, while ZnO considerably increased the antioxidant activity of the fibrous materials. Materials with design type "on" displayed over 70% radical scavenging capacity in contrast to the material type "in" with less than 20% capacity within 30 min of contact. Moreover, the purposely tailored design type "on" materials provided excellent photocatalytic degradation of model organic pollutant methylene blue dye under UV light irradiation even after 5-fold use, and at the end of the fifth cycle these materials degraded more than 90% of the dye. These results reveal not only a strategy for the fabrication of electrospun hybrid bio-based materials with targeted design but also provide a promising, simple and effective way for mitigating water pollution.
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The demand for modern electronics and semiconductors has increased throughout the years, which has enabled the innovation and exploration of solution-processed deposition. Solution-based processes have gained a lot of interest due to the low-cost fabrication and the large fabrication areas without the need for high-vacuum equipment. In this study, we utilized the ZnO ink for inkjet printer ink to fabricate a thin film via Electrohydrodynamic printing. Three different ink solutions were prepared for experimentation. The EHD printing technique demonstrated the ink's compatibility with and without the modifications. The outcomes of the EHD printed materials were comparable with the spin-coated thin films. The EHD-printed films demonstrated better results in comparison to spin-coated films. Ra and Rq of the EHD film measured at 3.651 nm and 4.973 nm, respectively. It improved the absorbance up to two-fold at 360 nm wavelength and electrical conductivity up to 40% compared to the spin-coated films. Furthermore, the optimization of the printing parameters can lead to the improved morphology and thickness of the EHD thin films.
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Electrospraying for Vitamin C (VC) encapsulation in Chitosan (Cs) nanoparticles was investigated and particle size, zeta potential, loading capacity (LC%) and encapsulation efficiency (EE%) were examined. Cs concentration (1-2% w/v) and voltage (21-25 kV) were varied with VC (0.25-0.75 w/w Cs). Twenty experiments in a face-centered CCD-RSM design were evaluated. ANOVA suggested voltage and Cs concentration as significant factors for particle size and VC content affected zeta, LC and EE%. RSM proposed optimum processing parameter at 2% Cs, 0.746 VC: Cs mass ratio and 21 kV voltage with 251.1 ± 59.03 nm particle size, 36.6% LC and an EE of 85.42%. Encapsulated particles were subjected to release behaviour, antioxidant property and analyzed through FTIR, DSC and XRD. Encapsulated VC had better antibacterial properties than Cs nanoparticles, and comparable VC retention in apple juice showed its effectiveness. Overall, nanoencapsulation of VC using electrospraying was successfully developed to be used in numerous food processing applications.
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Antioxidantes , Ácido Ascórbico , Quitosana , Nanopartículas , Antibacterianos/química , Antibacterianos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Ácido Ascórbico/química , Quitosana/química , Composição de Medicamentos , Malus/química , Nanopartículas/química , Tamanho da PartículaRESUMO
This research investigated the in vivo gelation, biodegradation, and drug release efficiency of a novel injectable sensitive drug delivery system for human growth hormone (HGh). This composite system comprises pH- and temperature-sensitive hydrogel, designated as oligomer serine-b-poly(lactide)-b-poly(ethylene glycol)-b-poly(lactide)-b-oligomer serine (OS-PLA-PEG-PLA-OS) pentablock copolymer, as matrix and electrosprayed HGh-loaded chitosan (HGh@CS) nanoparticles (NPs) as principal material. The proton nuclear magnetic resonance spectrum of the pH- and temperature-sensitive OS-PLA-PEG-PLA-OS pentablock copolymer hydrogel proved that this copolymer was successfully synthesized. The HGh was encapsulated in chitosan (CS) NPs by an electrospraying system in acetic acid with appropriate granulation parameters. The scanning electron microscopy images and size distribution showed that the HGh@CS NPs formed had an average diameter of 366.1 ± 214.5 nm with a discrete spherical shape and dispersed morphology. The sol-gel transition of complex gel based on HGh@CS NPs and OS-PLA-PEG-PLA-OS pentablock hydrogel was investigated at 15 °C and pH 7.8 in the sol state and gelled at 37 °C and pH 7.4, which is suitable for the physiological conditions of the human body. The HGh release experiment of the composite system was performed in an in vivo environment, which demonstrated the ability to release HGh, and underwent biodegradation within 32 days. The findings of the investigation revealed that the distribution of HGh@CS NPs into the hydrogel matrix not only improved the mechanical properties of the gel matrix but also controlled the drug release kinetics into the systematic bloodstream, which ultimately promotes the desired therapeutic body growth depending on the distinct concentration used.
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Quitosana , Portadores de Fármacos , Liberação Controlada de Fármacos , Hormônio do Crescimento Humano , Hidrogéis , Nanopartículas , Polietilenoglicóis , Temperatura , Quitosana/química , Concentração de Íons de Hidrogênio , Hormônio do Crescimento Humano/química , Hormônio do Crescimento Humano/administração & dosagem , Nanopartículas/química , Humanos , Hidrogéis/química , Polietilenoglicóis/química , Portadores de Fármacos/química , Poliésteres/química , Animais , InjeçõesRESUMO
Combination therapy with oral administration of several active ingredients is a popular clinical treatment for cancer. However, the traditional method has poor convenience, less safety, and low efficiency for patients. The combination of traditional pharmaceutical techniques and advanced material conversion methods can provide new solutions to this issue. In this research, a new kind of hybrid film was created via coaxial electrospraying, followed by a casting process. The films were composed of Reglan and 5-fluorouracil (5-FU)-loaded cellulose acetate (CA) core-shell particles in a polyvinylpyrrolidone (PVP) film matrix. Microscopic observations of these films demonstrated a solid cross section loaded with core-shell particles. X-ray diffraction and Fourier-transform infrared tests verified that the Reglan and 5-FU loaded in the films showed amorphous states and fine compatibilities with the polymeric matrices, i.e., PVP and CA, respectively. In vitro dissolution tests indicated that the films were able to provide the desired asynchronous dual-drug delivery, fast release of Reglan, and sustained release of 5-FU. The controlled release mechanisms were shown to be an erosion mechanism for Reglan and a typical Fickian diffusion mechanism for 5-FU. The protocols reported herein pioneer a new approach for fabricating biomaterials loaded with multiple drugs, each with its own controlled release behavior, for synergistic cancer treatment.
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Core-shell particles composed of polycaprolactone/polyvinyl alcohol (PCL/PVA) with pH sensitive properties were successfully fabricated by co-axial electrospraying in which PVA and PCL formed the shell and core layers respectively. The core-shell structure was confirmed by FTIR, DSC and SEM analysis. No chemical interaction between PVA and PCL core-shell were observed in the FTIR analysis. The RAD001 loaded core-shell particles showed a sustained and pH dependent drug release and was assayed via our previously developed HPLC method. After indirect treatment of the PF-A cells with the core-shell particles for 24 h and 5 days a decrease in cell viability was observed. Additionally, a comparison was made with our previously developed nanoparticles containing 2 %PVA-14 %SOL®-0.6 % RAD001, for the cell viability study on ependymoma. Our findings show that optimised core-shell particles exerted a significant effect for the 24 h and 5 day treatment however further studies are required to ensure toxicity of the control core-shell particles with no drug is reduced. In comparison, the 2 %PVA-14 %SOL®-0.6 %RAD001 uniaxial electrosprayed nanoparticles also exerted a toxicity effect decreasing cell viability with no toxicity observed for the control nanoparticles as well. Such pH-sensitive core-shell particles, which can degrade effectively in either acidic or neutral condition, have great potential for application in the biomedical field.
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Neoplasias Encefálicas , Sobrevivência Celular , Nanopartículas , Poliésteres , Álcool de Polivinil , Álcool de Polivinil/química , Poliésteres/química , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Encefálicas/tratamento farmacológico , Humanos , Linhagem Celular Tumoral , Nanopartículas/química , Concentração de Íons de Hidrogênio , Liberação Controlada de Fármacos , Criança , Portadores de Fármacos/química , Ependimoma/tratamento farmacológico , Tamanho da PartículaRESUMO
In this work, novel erythrocyte-shaped electrosprayed nanoparticles (EENPs) were designed and constructed by tri-axial electrospraying technique with PEG as the outer layer, PLGA as the middle drugs (paclitaxel [PTX] and osimertinib [OSI]) carrier layer and air as the inner layer. The prepared EENP were characterized and evaluated based on their spectral and morphological attributes. After the PTX/OSI ratio and process optimization, the EENP has inspiring features, including nanoscale size, erythrocyte morphology with a concave disk shape, and satisfactory drug loading (DL) and encapsulation efficiency (EE). In vitro drug release showed that PTX and OSI in the formulation were released in the same ratio, and the cumulative release percentage at 24 h was close to 80 %. Furthermore, the TGIR in the EENP formulation group exceeded 90 %, approximately 3.8-fold higher than that in the free drug group. In summary, we developed an erythrocyte three-core-shell nanoparticle for the co-delivery of PTX and OSI, providing a potential chemotherapeutic delivery system for the treatment of breast cancer.
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Acrilamidas , Compostos de Anilina , Portadores de Fármacos , Liberação Controlada de Fármacos , Eritrócitos , Nanopartículas , Paclitaxel , Paclitaxel/administração & dosagem , Paclitaxel/farmacocinética , Paclitaxel/química , Compostos de Anilina/química , Compostos de Anilina/farmacocinética , Compostos de Anilina/administração & dosagem , Acrilamidas/química , Nanopartículas/química , Portadores de Fármacos/química , Eritrócitos/efeitos dos fármacos , Humanos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Tamanho da Partícula , Polietilenoglicóis/química , Sistemas de Liberação de Medicamentos/métodos , Composição de Medicamentos/métodos , Indóis , PirimidinasRESUMO
The shapes of micro- and nano-products have profound influences on their functional performances, which has not received sufficient attention during the past several decades. Electrohydrodynamic atomization (EHDA) techniques, mainly include electrospinning and electrospraying, are facile in manipulate their products' shapes. In this review, the shapes generated using EHDA for modifying drug release profiles are reviewed. These shapes include linear nanofibers, round micro-/nano-particles, and beads-on-a-string hybrids. They can be further divided into different kinds of sub-shapes, and can be explored for providing the desired pulsatile release, sustained release, biphasic release, delayed release, and pH-sensitive release. Additionally, the shapes resulted from the organizations of electrospun nanofibers are discussed for drug delivery, and the shapes and inner structures can be considered together for developing novel drug delivery systems. In future, the shapes and the related shape-performance relationships at nanoscale, besides the size, inner structure and the related structure-performance relationships, would further play their important roles in promoting the further developments of drug delivery field. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies.
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Sistemas de Liberação de Medicamentos , Humanos , Nanofibras/química , Animais , Nanopartículas/química , HidrodinâmicaRESUMO
Quantum dots (QDs) are inorganic semiconductor nanocrystals capable of emitting light. The current major challenge lies in the use of heavy metals, which are known to be highly toxic to humans and pose significant environmental risks. Researchers have turned to indium (In) as a promising option for more environmentally benign QDs, specifically indium phosphide (InP). A significant obstacle remains in sustaining the long-term photostability of InP-based QDs when exposed to the environment. To tackle this, electrospraying is used in this work to protect indium phosphide/zinc selenide/zinc sulfide (InP/ZnSe/ZnS) QDs by embedding them within polymer core-shell microparticles of poly[(lauryl methacrylate)-co-(ethylene glycol dimethacrylate)]/poly(methyl methacrylate) (poly(LMA-co-EGDMA)/PMMA). During the flight of droplets, the liquid monomer core of LMA and EGDMA with QDs is encapsulated by the solid shell of PMMA formed due to solvent evaporation, resulting in a liquid-core/solid-shell particle structure. After that, the captured core of monomers is polymerized into a cross-linked polymer with the embedded QDs via a thermal initiation. They demonstrate how a successful core-shell particle formation is achieved to produce structures for initially liquid monomer systems via coaxial electrospraying that are used for cross-linked polymers, which are of major interest for the encapsulation of InP-based QDs for generally improved photostability over pristine QDs.
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The use of medicinal substances in nanosized forms (nanoforms, nanoparticles) allows the therapeutic effectiveness of pharmaceutical preparations to be increased due to several factors: (1) the high specific surface area of nanomaterials, and (2) the high concentration of surface-active centers interacting with biological objects. In the case of drug nanoforms, even low concentrations of a bioactive substance can have a significant therapeutic effect on living organisms. These effects allow pharmacists to use lower doses of active components, consequently lowering the toxic side effects of pharmaceutical nanoform preparations. It is known that many drug substances that are currently in development are poorly soluble in water, so they have insufficient bioavailability. Converting them into nanoforms will increase their rate of dissolution, and the increased saturation solubility of drug nanocrystals also makes a significant contribution to their high therapeutic efficiency. Some physical and chemical methods can contribute to the formation of both pure drug nanoparticles and their ligand or of polymer-covered nanoforms, which are characterized by higher stability. This review describes the most commonly used methods for the preparation of nanoforms (nanoparticles) of different medicinal substances, paying close attention to modern supercritical and cryogenic technologies and the advantages and disadvantages of the described methods and techniques; moreover, the improvements in the physico-chemical and biomedical properties of the obtained medicinal nanoforms are also discussed.
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This study investigates the encapsulation of Tenebrio molitor hydrolysate exhibiting DPP-IV inhibitory activity by spray-drying and electrospraying techniques. First, we optimized the feed formulation and processing conditions required to obtain nano-microcapsules by electrospraying when using Arabic gum as an encapsulating agent and pullulan and Tween 20 as additives. The optimum formulation was also dried by spray-drying, where the removal of the additives was also assayed. Morphology analysis reveals that electrosprayed capsules have a smaller size (1.2 ± 0.5 µm vs. 12.4 ± 8.7 µm) and greater uniformity compared to those obtained by spray-drying. Regarding the surface nitrogen content and DPP-IV inhibitory activity, our results show no significant difference between the electrosprayed capsules and spray-dried capsules containing additives (IC50 of ~1.5 mg protein/mL). Therefore, it was concluded that adding additives during spray-drying allows for a similar encapsulation efficiency and reduced degradation during processing, as achieved by electrospraying technique but providing higher productivity. On the other hand, spray-dried capsules without additives displayed a higher surface nitrogen content percentage, which was mainly due to the absence of Tween 20 in the feed formulation. Consequently, these capsules presented a higher IC50 value (IC50 of 1.99 ± 0.03 mg protein/mL) due to the potential degradation of surface-exposed peptides.
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A chronic nonhealing wound poses a significant risk for infection and subsequent health complications, potentially endangering the patient's well-being. Therefore, effective wound dressings must meet several crucial criteria, including: (1) eliminating bacterial pathogen growth within the wound, (2) forming a barrier against airborne microbes, (3) promoting cell proliferation, (4) facilitating tissue repair. In this study, we synthesized 8 ± 3 nm Ag NP with maleic acid and incorporated them into an electrospun polycaprolactone (PCL) matrix with 1.6 and 3.4 µm fiber sizes. The Ag NPs were anchored to the matrix via electrospraying water-soluble poly(vinyl) alcohol (PVA), reducing the average sphere size from 750 to 610 nm in the presence of Ag NPs. Increasing the electrospraying time of Ag NP-treated PVA spheres demonstrated a more pronounced antibacterial effect. The resultant silver-based material exhibited 100% inhibition of gram-negative Escherichia coli and gram-positive Staphylococcus aureus growth within 6 h while showing non-cytotoxic effects on the Vero cell line. We mainly discuss the preparation method aspects of the membrane, its antibacterial properties, and cytotoxicity, suggesting that combining these processes holds promise for various medical applications.
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Antibacterianos , Materiais Biocompatíveis , Escherichia coli , Poliésteres , Álcool de Polivinil , Prata , Staphylococcus aureus , Álcool de Polivinil/química , Álcool de Polivinil/farmacologia , Prata/química , Prata/farmacologia , Poliésteres/química , Antibacterianos/farmacologia , Antibacterianos/química , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Staphylococcus aureus/efeitos dos fármacos , Células Vero , Animais , Chlorocebus aethiops , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Nanopartículas Metálicas/química , Alicerces Teciduais/química , Testes de Sensibilidade MicrobianaRESUMO
Guided bone regeneration (GBR) membranes are widely used to treat bone defects. In this study, sequential electrospinning and electrospraying techniques were used to prepare a dual-layer GBR membrane composed of gelatin (Gel) and chitosan (CS) containing simvastatin (Sim)-loaded poly(lactic-co-glycolic acid) (PLGA) microspheres (Sim@PLGA/Gel-CS). As a GBR membrane, Sim@PLGA/Gel-CS could act as a barrier to prevent soft tissue from occupying regions of bone tissue. Furthermore, compared with traditional GBR membranes, Sim@PLGA/Gel-CS played an active role on stimulating osteogenesis and angiogenesis. Determination of the physical, chemical, and biological properties of Sim@PLGA/Gel-CS membranes revealed uniform sizes of the nanofibers and microspheres and appropriate morphologies. Fourier-transform infrared spectroscopy was used to characterize the interactions between Sim@PLGA/Gel-CS molecules and the increase in the number of amide groups in crosslinked membranes. The thermal stability and tensile strength of the membranes increased after N-(3-dimethylaminopropyl)-N9- ethylcarbodiimide/N-hydroxysuccinimide crosslinking. The increased fiber density of the barrier layer decreased fibroblast migration compared with that in the osteogenic layer. Osteogenic function was indicated by the increased alkaline phosphatase activity, calcium deposition, and neovascularization. In conclusion, the multifunctional effects of Sim@PLGA/Gel-CS on the barrier and bone microenvironment were achieved via its dual-layer structure and simvastatin coating. Sim@PLGA/Gel-CS has potential applications in bone tissue regeneration.
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Quitosana , Gelatina , Membranas Artificiais , Neovascularização Fisiológica , Osteogênese , Quitosana/química , Gelatina/química , Osteogênese/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Sinvastatina/química , Sinvastatina/farmacologia , Regeneração Óssea/efeitos dos fármacos , Regeneração Tecidual Guiada/métodos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Humanos , Animais , Alicerces Teciduais/química , Nanofibras/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Microesferas , AngiogêneseRESUMO
Physically unclonable functions (PUFs) have attracted growing interest for anticounterfeiting and authentication applications. The practical applications require durable PUFs made of robust materials. This study reports a practical strategy to generate extremely robust PUFs by embedding random features onto a substrate. The chaotic and low-cost electrohydrodynamic deposition process generates random polymeric features over a negative-tone photoresist film. These polymer features function as a conformal photomask, which protects the underlying photoresist from UV light, thereby enabling the generation of randomly positioned holes. Dry plasma etching of the substrate and removal of the photoresist result in the transfer of random features to the underlying silicon substrate. The matching of binary keys and features via different algorithms facilitates authentication of features. The embedded PUFs exhibit extreme levels of thermal (â¼1000 °C) and mechanical stability that exceed the state of the art. The strength of this strategy emerges from the PUF generation directly on the substrate of interest, with stability that approaches the intrinsic properties of the underlying material. Benefiting from the materials and processes widely used in the semiconductor industry, this strategy shows strong promise for anticounterfeiting and device security applications.
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This study reports on the two-step manufacturing process of a filtration media obtained by first electrospinning a layer of polycaprolactone (PCL) non-woven fibers onto a paper filter backing and subsequently coating it by electrospraying with a second layer made of pure acidolysis lignin. The manufacturing of pure lignin coatings by solution electrospraying represents a novel development that requires fine control of the underlying electrodynamic processing. The effect of increasing deposition time on the lignin coating was investigated for electrospray time from 2.5 min to 120 min. Microstructural and physical characterization included SEM, surface roughness analysis, porosity tests, permeability tests by a Gurley densometer, ATR-FTIR analysis, and contact angle measurements vs. both water and oil. The results indicate that, from a functional viewpoint, such a natural coating endowed the membrane with an amphiphilic behavior that enabled modulating the nature of the bare PCL non-woven substrate. Accordingly, the intrinsic hydrophobic behavior of bare PCL electrospun fibers could be reduced, with a marked decrease already for a thin coating of less than 50 nm. Instead, the wettability of PCL vs. apolar liquids was altered in a less predictable manner, i.e., producing an initial increase of the oil contact angles (OCA) for thin lignin coating, followed by a steady decrease in OCA for higher densities of deposited lignin. To highlight the effect of the lignin type on the results, two grades of oak (AL-OA) of the Quercus cerris L. species and eucalyptus (AL-EU) of the Eucalyptus camaldulensis Dehnh species were compared throughout the investigation. All grades of lignin yielded coatings with measurable antibacterial properties, which were investigated against Staphylococcus aureus and Escherichia coli, yielding superior results for AL-EU. Remarkably, the lignin coatings did not change overall porosity but smoothed the surface roughness and allowed modulating air permeability, which is relevant for filtration applications. The findings are relevant for applications of this abundant biopolymer not only for filtration but also in biotechnology, health, packaging, and circular economy applications in general, where the reuse of such natural byproducts also brings a fundamental demanufacturing advantage.