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1.
Int J Biol Macromol ; 262(Pt 2): 130141, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38365150

RESUMO

Exosomes are among the most effective therapeutic tools for tissue engineering. This study demonstrates that a 3D composite scaffold containing exosomes can promote regeneration in rat tympanic membrane perforation (TMP). The scaffolds were characterized using scanning electron microscopy (SEM), degradation, PBS adsorption, swelling, porosity, and mechanical properties. To confirm the isolation of exosomes from human adipose-derived mesenchymal stem cells (hAMSCs), western blot, SEM, and dynamic light scattering (DLS) were performed. The Western blot test confirmed the presence of exosomal surface markers CD9, CD81, and CD63. The SEM test revealed that the isolated exosomes had a spherical shape, while the DLS test indicated an average diameter of 82.5 nm for these spherical particles. MTT assays were conducted to optimize the concentration of hAMSCs-exosomes in the hydrogel layer of the composite. Exosomes were extracted on days 3 and 7 from an alginate hydrogel containing 100 and 200 µg/mL of exosomes, with 100 µg/mL identified as the optimal value. The optimized composite scaffold demonstrated improved growth and migration of fibroblast cells. Animal studies showed complete tympanic membrane regeneration (TM) after five days. These results illustrate that a scaffold containing hAMSC-exosomes can serve as an appropriate tissue-engineered scaffold for enhancing TM regeneration.


Assuntos
Exossomos , Células-Tronco Mesenquimais , Nanofibras , Perfuração da Membrana Timpânica , Ratos , Animais , Humanos , Gelatina , Hidrogéis , Alginatos , Alicerces Teciduais , Engenharia Tecidual/métodos
2.
J Funct Biomater ; 14(12)2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-38132810

RESUMO

Male survivors of childhood cancer have been known to be afflicted with azoospermia. To combat this, the isolation and purification of spermatogonial stem cells (SSCs) are crucial. Implementing scaffolds that emulate the extracellular matrix environment is vital for promoting the regeneration and proliferation of SSCs. This research aimed to evaluate the efficiency of nanocomposite scaffolds based on alginate, chitosan, and graphene oxide (GO) in facilitating SSCs proliferation. To analyze the cytotoxicity of the scaffolds, an MTT assay was conducted at 1, 3, and 7 days, and the sample containing 30 µg/mL of GO (ALGCS/GO30) exhibited the most favorable results, indicating its optimal performance. The identity of the cells was confirmed using flow cytometry with C-Kit and GFRα1 markers. The scaffolds were subjected to various analyses to characterize their properties. FTIR was employed to assess the chemical structure, XRD to examine crystallinity, and SEM to visualize the morphology of the scaffolds. To evaluate the proliferation of SSCs, qRT-PCR was used. The study's results demonstrated that the ALGCS/GO30 nanocomposite scaffold exhibited biocompatibility and facilitated the attachment and proliferation of SSCs. Notably, the scaffold displayed a significant increase in proliferation markers compared to the control group, indicating its ability to support SSC growth. The expression level of the PLZF protein was assessed using the Immunocytochemistry method. The observations confirmed the qRT-PCR results, which indicated that the nanocomposite scaffolds had higher levels of PLZF protein expression than scaffolds without GO. The biocompatible ALGCS/GO30 is a promising alternative for promoting SSC proliferation in in vitro applications.

3.
Molecules ; 28(24)2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38138471

RESUMO

Heparin, a highly sulfated glycosaminoglycan, is a naturally occurring anticoagulant that plays a vital role in various physiological processes. The remarkable structural complexity of heparin, consisting of repeating disaccharide units, makes it a crucial molecule for the development of commercial drugs in the pharmaceutical industry. Over the past few decades, significant progress has been made in the development of cost-effective adsorbents specifically designed for the adsorption of heparin from porcine intestinal mucosa. This advancement has been driven by the need for efficient and scalable methods to extract heparin from natural sources. In this study, we investigated the use of cationic ammonium-functionalized diatomaceous earth, featuring enhanced porosity, larger surface area, and higher thermal stability, to maximize the isolated heparin recovery. Our results showed that the higher cationic density and less bulky quaternary modified diatomaceous earth (QDADE) could adsorb up to 16.3 mg·g-1 (31%) of heparin from the real mucosa samples. Additionally, we explored the conditions of the adsorbent surface for recovery of the heparin molecule and optimized various factors, such as temperature and pH, to optimize the heparin uptake. This is the introductory account of the implementation of modified diatomaceous earth with quaternary amines for heparin capture.


Assuntos
Terra de Diatomáceas , Heparina , Animais , Suínos , Terra de Diatomáceas/química , Anticoagulantes , Temperatura , Mucosa Intestinal
4.
BMC Res Notes ; 16(1): 268, 2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37828608

RESUMO

OBJECTIVE: Polyvinyl alcohol (PVA) as a synthetic biopolymer has unique physicochemical properties to achieve an efficient drug carrier. In this study phenol-substituted polyvinyl alcohol (PVAPh) microparticle was made through a microfluidic system and peroxidase-mediated reaction in the presence of hydrogen peroxide and in following dexamethasone (Dex) release characteristics from this vehicle were elaborated for sustained drug delivery applications. RESULTS: PVAPh was synthesized by esterification and amidation reactions respectively. Then, the synthesized PVAPh solution containing peroxidase and Dex flowed within the inner channel of the coaxial microfluidic device while liquid paraffin saturated with H2O2 flowed from the outer channel. The monodisperse microparticles were produced in a spherical shape with an average diameter of 160 µm. The Dex was successfully encapsulated in PVAPh MP and its sustained release profile was maintained for up to 7 days. It was found that exposure of Dex-loaded PVAPh MPs to subcultured mouse embryonic fibroblast 10T1/2 cells had no deleterious effects on cell viability, morphology and growth rate. Moreover, the sustained release of Dex and the high mechanical durability of PVAPh MPs suggest an excellent prospect for the synthesized PVAPh and the developed method as a biocompatible carrier required for drug delivery and regenerative medicine.


Assuntos
Microfluídica , Álcool de Polivinil , Animais , Camundongos , Álcool de Polivinil/química , Preparações de Ação Retardada/química , Peróxido de Hidrogênio , Fibroblastos , Dexametasona/farmacologia , Peroxidases
5.
Mater Today Bio ; 22: 100778, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37664796

RESUMO

The interface tissue between bone and soft tissues, such as tendon and ligament (TL), is highly prone to injury. Although different biomaterials have been developed for TL regeneration, few address the challenges of the TL-bone interface. Here, we aim to develop novel hybrid nanocomposites based on poly(p-dioxanone) (PDO), poly(lactide-co-caprolactone) (LCL), and hydroxyapatite (HA) nanoparticles suitable for TL-bone interface repair. Nanocomposites, containing 3-10% of both unmodified and chemically modified hydroxyapatite (mHA) with a silane coupling agent. We then explored biocompatibility through in vitro and in vivo studies using a subcutaneous mouse model. Through different characterisation tests, we found that mHA increases tensile properties, creates rougher surfaces, and reduces crystallinity and hydrophilicity. Morphological observations indicate that mHA nanoparticles are attracted by PDO rather than LCL phase, resulting in a higher degradation rate for mHA group. We found that adding the 5% of nanoparticles gives a balance between the properties. In vitro experiments show that osteoblasts' activities are more affected by increasing the nanoparticle content compared with fibroblasts. Animal studies indicate that both HA and mHA nanoparticles (10%) can reduce the expression of pro-inflammatory cytokines after six weeks of implantation. In summary, this work highlights the potential of PDO/LCL/HA nanocomposites as an excellent biomaterial for TL-bone interface tissue engineering applications.

6.
Int J Biol Macromol ; 238: 124098, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-36948341

RESUMO

Stem cell therapy is a promising strategy for cartilage tissue engineering, and cell transplantation using polymeric scaffolds has recently gained attention. Herein, we encapsulated human adipose-derived stem cells (hASCs) within the alginate sulfate hydrogel and then added them to polycaprolactone/gelatin electrospun nanofibers and extracellular matrix (ECM) powders to mimic the cartilage structure and characteristic. The composite hydrogel scaffolds were developed to evaluate the relevant factors and conditions in mechanical properties, cell proliferation, and differentiation to enhance cartilage regeneration. For this purpose, different concentrations (1-5 % w/v) of ECM powder were initially loaded within an alginate sulfate solution to optimize the best composition for encapsulated hASCs viability. Adding 4 % w/v of ECM resulted in optimal mechanical and rheological properties and better cell viability. In the next step, electrospun nanofibrous layers were added to the alginate sulfate/ECM composite to prepare different layered hydrogel-nanofiber (2, 3, and 5-layer) structures with the ability to mimic the cartilage structure and function. The 3-layer structure was selected as the optimum layered composite scaffold, considering cell viability, mechanical properties, swelling, and biodegradation behavior; moreover, the chondrogenesis potential was assessed, and the results showed promising features for cartilage tissue engineering application.


Assuntos
Nanofibras , Engenharia Tecidual , Humanos , Engenharia Tecidual/métodos , Nanofibras/química , Alicerces Teciduais/química , Hidrogéis/química , Alginatos/metabolismo , Sulfatos/metabolismo , Cartilagem , Matriz Extracelular/metabolismo , Células-Tronco
7.
Bioact Mater ; 25: 291-306, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36844365

RESUMO

Biopolymers play a critical role as scaffolds used in tendon and ligament (TL) regeneration. Although advanced biopolymer materials have been proposed with optimised mechanical properties, biocompatibility, degradation, and processability, it is still challenging to find the right balance between these properties. Here, we aim to develop novel hybrid biocomposites based on poly(p-dioxanone) (PDO), poly(lactide-co-caprolactone) (LCL) and silk to produce high-performance grafts suitable for TL tissue repair. Biocomposites containing 1-15% of silk were studied through a range of characterisation techniques. We then explored biocompatibility through in vitro and in vivo studies using a mouse model. We found that adding up to 5% silk increases the tensile properties, degradation rate and miscibility between PDO and LCL phases without agglomeration of silk inside the composites. Furthermore, addition of silk increases surface roughness and hydrophilicity. In vitro experiments show that the silk improved attachment of tendon-derived stem cells and proliferation over 72 h, while in vivo studies indicate that the silk can reduce the expression of pro-inflammatory cytokines after six weeks of implantation. Finally, we selected a promising biocomposite and created a prototype TL graft based on extruded fibres. We found that the tensile properties of both individual fibres and braided grafts could be suitable for anterior cruciate ligament (ACL) repair applications.

8.
ACS Omega ; 8(1): 1710-1722, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36643556

RESUMO

Enzymatic degradation of polymers has advantages over standard degradation methods, such as soil burial and weathering, which are time-consuming and cannot provide time-resolved observations. We have developed a microfluidic device to study the degradation of single microparticles. The enzymatic degradation of poly (1,4-butylene adipate-co-terephthalate) (PBAT) microparticles was studied using Novozym 51032 cutinase. PBAT microparticles were prepared via an oil-in-water emulsion solvent removal method, and their morphology and chemical composition were characterized. Then, microparticles with varying diameters of 30-60 µm were loaded into the microfluidic chip. Enzyme solutions at different concentrations were introduced to the device, and changes in the size and transparency of PBAT microparticles were observed over time. The physicochemical properties of degraded products were analyzed by FT-IR, NMR, mass spectrometry, and differential scanning calorimetry. The degradation process was also performed in bulk, and the results were compared to those of the microfluidic method. Our analysis confirms that the degradation process in both bulk and microfluidic methods was similar. In both cases, degradation takes place on aliphatic and soft segments of PBAT. Our findings serve as a proof of concept for a microfluidic method for easy and time-resolved degradation analysis, with degradation results comparable to those of conventional bulk methods.

9.
Bioengineering (Basel) ; 9(11)2022 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-36354517

RESUMO

Heparin, usually isolated from porcine intestinal mucosa, is an active pharmaceutical ingredient of great material value. Traditionally, diverse types of commercial resins were employed as an adsorbent for heparin retrieval from biological samples. However, more recent years have encouraged the advent of new cost-effective adsorbents to achieve enhanced heparin retrieval. Inexpensive cationic ammonium-functionalized silica gels, monodispersed with larger surface area, porosity, and higher thermal stability, were chosen to evaluate the heparin recovery yield from porcine intestinal mucosa. We demonstrated that higher positively charged and less bulky quaternary modified silica gel (e.g., QDASi) could adsorb ~28% (14.7 mg g-1) heparin from the real samples. In addition, we also determined suitable surface conditions for the heparin molecule adsorption by mechanistic studies and optimized different variables, such as pH, temperature, etc., to improve the heparin adsorption. This is going to be the first reported study on the usage of quaternary amine-functionalized silica gel for HEP uptake.

10.
J Agric Food Chem ; 70(30): 9399-9411, 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35881537

RESUMO

Vegetable oils with varying saturated fat levels were inoculated with Lacticaseibacillus rhamnosus GG (LGG), subjected to different heat treatments in the absence and presence of inulin and stored for 12 months at room temperature. After storage, the heat-treated probiotics actively grew to high concentrations after removal of the oils and reculturing. The bacterial samples, regardless of aerobic or anaerobic conditions and treatment methods, showed no changes in their growth behavior. The random amplified polymorphic DNA-polymerase chain reaction, antimicrobial, morphology, and motility tests also showed no major differences. Samples of LGG treated with a higher antioxidant content (Gal400) showed reduced inflammatory and anti-inflammatory properties. These findings have been confirmed by metabolite and genome sequencing studies, indicating that Gal400 showed lower concentrations and secretion percentages and the highest number of single nucleotide polymorphisms. We have shown proof of concept that LGG can be stored in oil with minimum impact on probiotic in vitro viability.


Assuntos
Lacticaseibacillus rhamnosus , Probióticos , Inulina , Óleos de Plantas , Temperatura
11.
J Biomed Mater Res A ; 110(6): 1199-1209, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35098649

RESUMO

Various composite scaffolds with different fabrication techniques have been applied in cartilage tissue engineering. In this study, poly ɛ-caprolactone (PCL) was printed by fused deposition modeling method, and the prepared scaffold was filled with Alginate (Alg): Alginate-Sulfate (Alg-Sul) hydrogel to provide a better biomimetic environment and emulate the structure of glycosaminoglycans properly. Furthermore, to enhance chondrogenesis, different concentrations of decellularized extracellular matrix (dECM) were added to the hydrogel. For cellular analyses, the adipose-derived mesenchymal stem cells were seeded on the hydrogel and the results of MTT assay, live/dead staining, and SEM images revealed that the scaffold with 1% dECM had better viscosity, cell viability, and proliferation. The study was conducted on the optimized scaffold (1% dECM) to determine mechanical characteristics, chondrogenic differentiation, and results demonstrated that the scaffold showed mechanical similarity to the native nasal cartilage tissue along with possessing appropriate biochemical features, which makes this new formulation based on PCL/dECM/Alg:Alg-Sul a promising candidate for further in-vivo studies.


Assuntos
Alginatos , Alicerces Teciduais , Alginatos/química , Alginatos/farmacologia , Caproatos , Condrogênese , Matriz Extracelular/química , Lactonas , Cartilagens Nasais , Impressão Tridimensional , Regeneração , Sulfatos , Engenharia Tecidual/métodos , Alicerces Teciduais/química
12.
Sci Rep ; 11(1): 16608, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-34400694

RESUMO

There is growing interest among the public and scientific community toward the use of probiotics to potentially restore the composition of the gut microbiome. With the aim of preparing eco-friendly probiotic edible films, we explored the addition of probiotics to the seed mucilage films of quince, flax, and basil. These mucilages are natural and compatible blends of different polysaccharides that have demonstrated medical benefits. All three seed mucilage films exhibited high moisture retention regardless of the presence of probiotics, which is needed to help preserve the moisture/freshness of food. Films from flax and quince mucilage were found to be more thermally stable and mechanically robust with higher elastic moduli and elongation at break than basil mucilage films. These films effectively protected fruits against UV light, maintaining the probiotics viability and inactivation rate during storage. Coated fruits and vegetables retained their freshness longer than uncoated produce, while quince-based probiotic films showed the best mechanical, physical, morphological and bacterial viability. This is the first report of the development, characterization and production of 100% natural mucilage-based probiotic edible coatings with enhanced barrier properties for food preservation applications containing probiotics.


Assuntos
Filmes Comestíveis , Conservação de Alimentos/métodos , Frutas , Mucilagem Vegetal , Probióticos/administração & dosagem , Verduras , Técnicas de Química Analítica , Módulo de Elasticidade , Linho/química , Lacticaseibacillus rhamnosus , Teste de Materiais , Viabilidade Microbiana , Microscopia Confocal , Microscopia Eletrônica de Varredura , Ocimum basilicum/química , Permeabilidade , Rosaceae/química , Sementes/química , Propriedades de Superfície , Resistência à Tração , Água
13.
Carbohydr Polym ; 266: 118123, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34044939

RESUMO

In this study, we fabricated two different arrangements of laminated composite scaffolds based on Alginate:Alginate sulfate hydrogel, PCL:Gelatin electrospun mat, and Kartogenin-PLGA nanoparticles (KGN-NPs). The optimized composite scaffold revealed a range of advantages such as improved mechanical features as well as less potential of damage (less dissipated energy), interconnected pores of hydrogel and fiber with adequate pore size, excellent swelling ratio, and controlled biodegradability. Furthermore, the synthesized KGN-NPs with spherical morphology were incorporated into the composite scaffold and exhibited a linear and sustained release of KGN within 30 days with desirable initial burst reduction (12% vs. 20%). Additionally, the cytotoxicity impact of the composite was evaluated. Resazurin assay and Live/Dead staining revealed that the optimized composite scaffold has no cytotoxic effect and could improve cell growth. Overall, according to the enhanced mechanical features, suitable environment for cellular growth, and sustained drug release, the optimized scaffold would be a good candidate for tissue regeneration.


Assuntos
Alginatos/química , Portadores de Fármacos/química , Hidrogéis/química , Células-Tronco Mesenquimais/efeitos dos fármacos , Nanofibras/química , Alicerces Teciduais/química , Anilidas/química , Anilidas/farmacologia , Liberação Controlada de Fármacos , Gelatina/química , Humanos , Nanopartículas/química , Ácidos Ftálicos/química , Ácidos Ftálicos/farmacologia , Poliésteres/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Engenharia Tecidual/instrumentação , Engenharia Tecidual/métodos
14.
J Mater Chem B ; 9(10): 2532-2546, 2021 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-33660730

RESUMO

Finding the right balance in mechanical properties and degradation rate of biodegradable materials for biomedical applications is challenging, not only at the time of implantation but also during biodegradation. For instance, high elongation at break and toughness with a mid-term degradation rate are required for tendon scaffold or suture application, which cannot be found in each alpha polyester individually. Here, we hypothesise that blending semi-crystalline poly(p-dioxanone) (PDO) and poly(lactide-co-caprolactone) (LCL) in a specific composition will enhance the toughness while also enabling tailored degradation times. Hence, blends of PDO and LCL (PDO/LCL) were prepared in varying concentrations and formed into films by solvent casting. We thoroughly characterised the chemical, thermal, morphological, and mechanical properties of the new blends before and during hydrolytic degradation. Cellular performance was determined by seeding mouse fibroblasts onto the samples and culturing for 72 hours, before using proliferation assays and confocal imaging. We found that an increase in LCL content causes a decrease in hydrolytic degradation rate, as indicated by induced crystallinity, surface and bulk erosions, and tensile properties. Interestingly, the noncytotoxic blend containing 30% PDO and 70% LCL (PDO3LCL7) resulted in small PDO droplets uniformly dispersed within the LCL matrix and demonstrated a tailored degradation rate and toughening behaviour with a notable strain-hardening effect reaching 320% elongation at break; over 3 times the elongation of neat LCL. In summary, this work highlights the potential of PDO3LCL7 as a biomaterial for biomedical applications like tendon tissue engineering or high-performance absorbable sutures.


Assuntos
Materiais Biocompatíveis/química , Dioxanos/química , Poliésteres/química , Polímeros/química , Engenharia Tecidual/métodos , Animais , Materiais Biocompatíveis/uso terapêutico , Linhagem Celular , Proliferação de Células , Fibroblastos/citologia , Fibroblastos/metabolismo , Congelamento , Hidrólise , Interações Hidrofóbicas e Hidrofílicas , Cinética , Ligamentos , Camundongos , Temperatura , Tendões , Resistência à Tração , Fatores de Tempo
15.
Biochem Biophys Rep ; 25: 100905, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33553683

RESUMO

Functional improvement after spinal cord injury remains an unsolved difficulty. Glial scars, a major component of SCI lesions, are very effective in improving the rate of this recovery. Such scars are a result of complex interaction mechanisms involving three major cells, namely, astrocytes, oligodendrocytes, and microglia. In recent years, scientists have identified two subtypes of reactive astrocytes, namely, A1 astrocytes that induce the rapid death of neurons and oligodendrocytes, and A2 astrocytes that promote neuronal survival. Moreover, recent studies have suggested that the macrophage polarization state is more of a continuum between M1 and M2 macrophages. M1 macrophages that encourage the inflammation process kill their surrounding cells and inhibit cellular proliferation. In contrast, M2 macrophages promote cell proliferation, tissue growth, and regeneration. Furthermore, the ability of oligodendrocyte precursor cells to differentiate into adult oligodendrocytes or even neurons has been reviewed. Here, we first scrutinize recent findings on glial cell subtypes and their beneficial or detrimental effects after spinal cord injury. Second, we discuss how we may be able to help the functional recovery process after injury.

16.
Int J Biol Macromol ; 177: 92-99, 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33609579

RESUMO

It is a critical challenge to protect hydrophilic compounds in food or pharmaceutical applications due to their strong tendency to leak out of the capsules into the external aqueous phase. In this work, we developed an encapsulation system that can protect hydrophilic ingredients using polyelectrolyte complexes prepared with chitosan and alginate via water-in-oil (W/O) emulsion. Unlike the traditional preparation of hydrogel beads, in which one material was added dropwise to another that had an opposite charge, we prepared microcapsules by electrostatic interaction between the positively charged -NH3+ groups of chitosan and the negatively charged -COO- groups of alginate by W/O emulsion via ultrasonication, which prevented the formation of large complexes. The preparation conditions were optimized at an ultrasonic power of 375 W and alginate/chitosan ratio of 7:5, in which the alginate/chitosan microcapsules presented a good polydispersity index of 0.26 and zeta potential of -44.6 mV. The SEM and TEM images showed the microcapsule contained multiple, irregular, conglutinated spheres with a core and shell structure. High encapsulation efficiency and retention efficiency showed its potential to protect hydrophilic components from harsh environments. This method provides a simple route that can efficiently encapsulate a wide range of food or pharmaceutical hydrophilic ingredients.


Assuntos
Alginatos/química , Cápsulas/química , Quitosana/química , Emulsões/química , Hidrogéis/química , Interações Hidrofóbicas e Hidrofílicas , Tamanho da Partícula , Eletricidade Estática , Água/química
17.
Int J Biol Macromol ; 171: 158-165, 2021 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-33418040

RESUMO

Superhydrophobic cotton fabrics were fabricated using chitosan/titanium dioxide (TiO2) nanocomposites. Morphology results revealed that the fabric's surface was utterly coated by the nanoparticles leading to the formation of a highly packed nano-scale structure in the case of superhydrophobic coating. X-ray photoelectron spectroscopy results also proved that TiO2 nanoparticles were highly adsorbed onto the fabric's top layer. Durability of the superhydrophobic coating was investigated by immersing the fabric into harsh solutions and also by subjecting the fabric to sonication. The results showed the high resistance of the superhydrophobic fabric against harsh conditions. The nanocomposite-coated fabrics were found to exhibit promising UV-protecting properties especially for the superhydrophobic fabric which showed around 80% enhancement in the UV protecting properties as compared with the uncoated fabric. The bacterial adhesion results revealed that the combination of chitosan and TiO2 results in high antibacterial properties against E. coli and S. aureus bacteria. The bacterial reduction percentages were further increased to 99.8 and 97.3% against E. coli and S. aureus, respectively, once the superhydrophobic character was also induced to the fabrics. The developed nanocomposite coated fabrics exhibited promising potential to be used as antibacterial and self-cleaning garments in hospital-related applications.


Assuntos
Antibacterianos/farmacologia , Quitosana/farmacologia , Nanocompostos/química , Nanopartículas/química , Protetores Solares/farmacologia , Titânio/farmacologia , Antibacterianos/química , Quitosana/química , Fibra de Algodão/análise , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Humanos , Interações Hidrofóbicas e Hidrofílicas , Testes de Sensibilidade Microbiana , Nanocompostos/ultraestrutura , Nanopartículas/ultraestrutura , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Protetores Solares/química , Têxteis/análise , Titânio/química
18.
Int J Biol Macromol ; 164: 4065-4072, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32910961

RESUMO

Plastic waste is one of the major threats to the environment, and an urgent need to replace synthetic plastics with sustainable materials is progressively growing. Herein, sustainable films based on chitosan, Satureja, and Thyme essential oils (EOs), and chitosan nanofibers (NF) were developed for the first time. To this end, 1% (w/w) of EOs and 2 wt% of NF were incorporated into the chitosan solution. Despite the very similar chemical structure of carvacrol and thymol, which are the major constituents of Satureja and Thyme EOs, respectively, they imposed notably different effects on the physicochemical properties of chitosan films. Thyme EO was more efficient at establishing hydrogen bonds with chitosan. The disruptive effect of EOs on the crystalline network of chitosan was demonstrated through X-ray diffraction analysis. Satureja and Thyme EOs decreased and increased the barrier property of the chitosan films against water vapor, respectively. However, the barrier property was greatly improved in the presence of chitosan nanofibers. Satureja EO exhibited a more efficient antibacterial property against E. coli rather than Thyme EO. The fruits and vegetables, coated by the chitosan/EO/NF system, were less perished as compared with the control and chitosan-coated samples indicating the promising potential of the developed system to be used as edible and sustainable films and coatings due to their enhanced antibacterial and barrier properties.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Quitosana/química , Filmes Comestíveis , Escherichia coli/química , Nanofibras/química , Fenômenos Químicos , Materiais Revestidos Biocompatíveis/química , Fenômenos Mecânicos , Testes de Sensibilidade Microbiana , Nanofibras/ultraestrutura , Análise Espectral
19.
Int J Biol Macromol ; 164: 356-370, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32682976

RESUMO

One of the most effective approaches for treatment of chronic rhinosinusitis is the use of hydrogel scaffolds with the sustained release of a given required drug. With this in mind, first, we synthesized and characterized poly (lactide-co-glycolide) (PLGA) micro and nano particles loaded with dexamethasone (DEX). We observed a 7-day release of DEX from nanoparticles, while the microparticles showed a 22-day release profile. Due to their slower rate of release, the PLGA microparticles loaded with DEX (PLGADEX microparticles) were specifically chosen for this study. As a second step, chitosan/polyvinylpyrrolidone (PVP) based hydrogels were prepared in various weight ratios and the PLGADEX microparticles were optimized in their structure based on variable gelation times. The morphological studies showed PLGADEX microparticles homogenously dispersed in the hydrogels. Moreover, the effect of weight ratio in the presence and absence of optimum percentage of PLGADEX microparticles was studied. The resultant hydrogels demonstrated a range of advantages, including good mechanical strength, porous morphology, amorphous structure, high swelling ratio, controlled biodegradability rate, and antibacterial activity. Additionally, a cytotoxicity analysis confirmed that the hydrogel scaffolds do not have adverse effects on the cells; our release studies in the hydrogel with the highest PVP content also showed 80% release after 30 days. Based on these results we were able to predict and control some of the mechanical properties, including the microstructure of the scaffolds, as well as the drug release, by optimizing the polymers - microparticle concentration, plus their resulting interactions. This optimized hydrogel can become part of a suitable alternative for treatment of allergic rhinitis and chronic sinusitis.


Assuntos
Quitosana/química , Dexametasona/administração & dosagem , Portadores de Fármacos/química , Hidrogéis/química , Microesferas , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Pesquisa Biomédica/métodos , Fenômenos Químicos , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Hidrólise , Tamanho da Partícula , Porosidade , Análise Espectral , Engenharia Tecidual
20.
J Biomater Sci Polym Ed ; 31(7): 910-937, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32009574

RESUMO

This study aimed to examine the possibility of using insulin orally with gelatin encapsulation to enhance the usefulness of the drug and increase the lifespan of insulin in the body using polylactic-co-glycolic acid (PLGA) nanoparticles alongside gelatin encapsulation. In this regard, PLGA was synthesized via ring opening polymerization, and PLGA/insulin nanoparticles were prepared by a modified emulsification-diffusion process. The resulting nanoparticles with various amounts of insulin were fully characterized using FTIR, DSC, DLS, zeta potential, SEM, and glucose uptake methods, with results indicating the interaction between the insulin and PLGA. The process efficiency of encapsulation was higher than 92%, while the encapsulation efficiency of nanoparticles, based on an insulin content of 20 to 40%, was optimized at 93%. According to the thermal studies, the PLGA encapsulation increases the thermal stability of the insulin. The morphological studies showed the fine dispersion of insulin in the PLGA matrix, which we further confirmed by the Kjeldahl method. According to the release studies and kinetics, in-vitro degradation, and particle size analysis, the sample loaded with 30% insulin showed optimum overall properties, and thus it was encapsulated with gelatin followed by coating with aqueous methacrylate coating. Release studies at pH values of 3 and 7.4, alongside the Kjeldahl method and standard dissolution test at pH 5.5, and glucose uptake assay tests clearly showed the capsules featured 3-4 h biodegradation resistance at a lower pH along with the sustained release, making these gelatin-encapsulated nanoparticles promising alternatives for oral applications.[Figure: see text].


Assuntos
Portadores de Fármacos/química , Gelatina/química , Insulina/química , Metacrilatos/química , Nanopartículas/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Cápsulas , Preparações de Ação Retardada , Concentração de Íons de Hidrogênio , Temperatura
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