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1.
J Nanobiotechnology ; 21(1): 259, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37550715

RESUMO

Autogenous bone grafting has long been considered the gold standard for treating critical bone defects. However, its use is plagued by numerous drawbacks, such as limited supply, donor site morbidity, and restricted use for giant-sized defects. For this reason, there is an increasing need for effective bone substitutes to treat these defects. Mollusk nacre is a natural structure with outstanding mechanical property due to its notable "brick-and-mortar" architecture. Inspired by the nacre architecture, our team designed and fabricated a nacre-mimetic cerium-doped layered nano-hydroxyapatite/chitosan layered composite scaffold (CeHA/CS). Hydroxyapatite can provide a certain strength to the material like a brick. And as a polymer material, chitosan can slow down the force when the material is impacted, like an adhesive. As seen in natural nacre, the combination of these inorganic and organic components results in remarkable tensile strength and fracture toughness. Cerium ions have been demonstrated exceptional anti-osteoclastogenesis capabilities. Our scaffold featured a distinct layered HA/CS composite structure with intervals ranging from 50 to 200 µm, which provided a conducive environment for human bone marrow mesenchymal stem cell (hBMSC) adhesion and proliferation, allowing for in situ growth of newly formed bone tissue. In vitro, Western-blot and qPCR analyses showed that the CeHA/CS layered composite scaffolds significantly promoted the osteogenic process by upregulating the expressions of osteogenic-related genes such as RUNX2, OCN, and COL1, while inhibiting osteoclast differentiation, as indicated by reduced TRAP-positive osteoclasts and decreased bone resorption. In vivo, calvarial defects in rats demonstrated that the layered CeHA/CS scaffolds significantly accelerated bone regeneration at the defect site, and immunofluorescence indicated a lowered RANKL/OPG ratio. Overall, our results demonstrate that CeHA/CS scaffolds offer a promising platform for bone regeneration in critical defect management, as they promote osteogenesis and inhibit osteoclast activation.


Assuntos
Quitosana , Nácar , Ratos , Humanos , Animais , Quitosana/farmacologia , Quitosana/química , Durapatita/farmacologia , Durapatita/química , Alicerces Teciduais/química , Nácar/farmacologia , Regeneração Óssea , Osteogênese , Transdução de Sinais , Diferenciação Celular , Engenharia Tecidual/métodos
2.
Molecules ; 28(3)2023 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-36770786

RESUMO

Agglomeration is an undesirable phenomenon that often occurs in spray-dried microcapsules powder. The objective of this work is to determine the best solution for spray-dried hydroxypropyl-ß-cyclodextrin (HP-ß-CD) microcapsules from four anticaking agents, namely calcium stearate (CaSt), magnesium stearate (MgSt), silicon dioxide (SiO2), and mannitol (MAN), and to explore their anticaking mechanisms. Our results showed that MAN was found to be the superior anticaking agent among those tested. When the MAN ratio is 12%, the microcapsules with a special Xanthium-type shape had higher powder flowability and lower hygroscopicity and exhibited good anticaking properties. Mechanism research revealed that CaSt, MgSt, and SiO2 reduce hygroscopicity and caking by increasing the glass transition temperature of the microcapsules, while MAN prevents the hydroxyl group of HP-ß-CD from combining with water molecules in the air by a crystal outer-layer on the microcapsule surface.

3.
J Nanobiotechnology ; 20(1): 28, 2022 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-34998407

RESUMO

Impaired angiogenesis is one of the predominant reasons for non-healing diabetic wounds. Herein, a nanofiber/hydrogel core-shell scaffold with three-dimensional (3D) multilayer patterned structure (3D-PT-P/GM) was introduced for promoting diabetic wound healing with improved angiogenesis. The results showed that the 3D-PT-P/GM scaffolds possessed multilayered structure with interlayer spacing of about 15-80 µm, and the hexagonal micropatterned structures were uniformly distributed on the surface of each layer. The nanofibers in the scaffold exhibited distinct core-shell structures with Gelatin methacryloyl (GelMA) hydrogel as the shell and Poly (D, L-lactic acid) (PDLLA) as the core. The results showed that the porosity, water retention time and water vapor permeability of the 3D-PT-P/GM scaffolds increased to 1.6 times, 21 times, and 1.9 times than that of the two-dimensional (2D) PDLLA nanofibrous scaffolds, respectively. The in vitro studies showed that the 3D-PT-P/GM scaffolds could significantly promote cell adhesion, proliferation, infiltration and migration throughout the scaffolds, and the expression of cellular communication protein-related genes, as well as angiogenesis-related genes in the same group, was remarkably upregulated. The in vivo results further demonstrated that the 3D-PT-P/GM scaffolds could not only effectively absorb exudate and provide a moist environment for the wound sites, but also significantly promote the formation of a 3D network of capillaries. As a result, the healing of diabetic wounds was accelerated with enhanced angiogenesis, granulation tissue formation, and collagen deposition. These results indicate that nanofiber/hydrogel core-shell scaffolds with 3D multilayer patterned structures could provide a new strategy for facilitating chronic wound healing.


Assuntos
Hidrogéis , Nanofibras , Alicerces Teciduais , Cicatrização/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Células Cultivadas , Complicações do Diabetes/patologia , Gelatina , Humanos , Metacrilatos , Neovascularização Fisiológica/efeitos dos fármacos
4.
J Nanobiotechnology ; 19(1): 11, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33413447

RESUMO

BACKGROUND: Breast cancer bone metastasis has become one of the most common complications; however, it may cause cancer recurrence and bone nonunion, as well as local bone defects. METHODS: Herein, In vitro, we verified the effect of bioscaffold materials on cell proliferation and apoptosis through a CCK8 trial, staining of live/dead cells, and flow cytometry. We used immunofluorescence technology and flow cytometry to verify whether bioscaffold materials regulate macrophage polarization, and we used ALP staining, alizarin red staining and PCR to verify whether bioscaffold material promotes bone regeneration. In vivo, we once again studied the effect of bioscaffold materials on tumors by measuring tumor volume in mice, Tunel staining, and caspase-3 immunofluorescence. We also constructed a mouse skull ultimate defect model to verify the effect on bone regeneration. RESULTS: Graphene oxide (GO) nanoparticles, hydrated CePO4 nanorods and bioactive chitosan (CS) are combined to form a bioactive multifunctional CePO4/CS/GO scaffold, with characteristics such as photothermal therapy to kill tumors, macrophage polarization to promote blood vessel formation, and induction of bone formation. CePO4/CS/GO scaffold activates the caspase-3 proteasein local tumor cells, thereby lysing the DNA between nucleosomes and causing apoptosis. On the one hand, the as-released Ce3+ ions promote M2 polarization of macrophages, which secretes vascular endothelial growth factor (VEGF) and Arginase-1 (Arg-1), which promotes angiogenesis. On the other hand, the as-released Ce3+ ions also activated the BMP-2/Smad signaling pathway which facilitated bone tissue regeneration. CONCLUSION: The multifunctional CePO4/CS/GO scaffolds may become a promising platform for therapy of breast cancer bone metastases.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Cério/química , Grafite/farmacologia , Nanotubos/química , Fosfatos/química , Células 3T3 , Animais , Materiais Biocompatíveis , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/metabolismo , Regeneração Óssea , Osso e Ossos , Neoplasias da Mama/metabolismo , Proliferação de Células , Quitosana , Modelos Animais de Doenças , Feminino , Macrófagos , Camundongos , Metástase Neoplásica , Osteogênese , Células RAW 264.7 , Ratos , Ratos Sprague-Dawley , Fator A de Crescimento do Endotélio Vascular
5.
Macromol Rapid Commun ; 41(3): e1900579, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31867797

RESUMO

A method for generating hierarchical scaffolds with graded changes in porosity and/or fiber alignment through solution-masked, vapor-induced welding of electrospun poly(lactic-co-glycolic acid) (PLGA) nanofibers is reported. The success of this method relies on the fact that the PLGA nanofibers are swollen and welded more slowly by ethanol when immersed in its aqueous solution relative to direct exposure to its vapor. For a mat composed of random nanofibers, the treatment generates a gradation in porosity (both surface and bulk), with the over-welded region evolving from a highly porous mat into a dense film. If uniaxially aligned nanofibers are involved, however, graded changes are observed in both surface porosity and fiber alignment. When bone marrow stem cells are cultured on such a scaffold, they exhibit highly organized and random morphologies on the regions of uniaxially aligned nanofibers and dense film, respectively, with gradual changes in between. Such a scaffold shows promise in mimicking the connective tissue, such as the tendon-to-bone insertion, that relies on a graded transition in cell morphology from uniaxially aligned to random.


Assuntos
Glicolatos/química , Nanofibras/química , Poliésteres/química , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Tecido Conjuntivo , Células-Tronco Hematopoéticas/citologia , Cinética , Nanofibras/ultraestrutura , Porosidade
6.
Nanomedicine ; 18: 336-346, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30419364

RESUMO

Bioglass scaffolds have great application potentials in orthopedics, and Ursolic acid (UA) can effectively promote in vivo new bone formation. Herein, we for the first time developed the mesoporous bioglass/chitosan porous scaffolds loaded with UA (MBG/CS/UA) for enhanced bone regeneration. The MBG microspheres with particle sizes of ~300 nm and pore sizes of ~3.9 nm were uniformly dispersed on the CS films. The mesoporous structure within the MBG microspheres and the hydrogen bonding between the scaffolds and UA drugs made the MBG/CS/UA scaffolds have controlled drug release performances. The as-released UA drugs from the scaffolds increased remarkably the alkaline phosphatase activity, osteogenic differentiation related gene type I collagen, runt-related transcription factor 2 expression, and osteoblast-associated protein expression. Moreover, the results of micro-CT images, histomorphological observations demonstrated that the MBG/CS/UA scaffolds improved new bone formation ability. Therefore, the MBG/CS/UA porous scaffolds can be used as novel bone tissue engineering materials.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Cerâmica/química , Quitosana/química , Sistemas de Liberação de Medicamentos , Alicerces Teciduais/química , Triterpenos/farmacologia , Animais , Linhagem Celular , Colágeno Tipo I/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Liberação Controlada de Fármacos , Feminino , Humanos , Camundongos , Microesferas , Osseointegração/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Porosidade , Ratos Sprague-Dawley , Ácido Ursólico
7.
J Nanobiotechnology ; 16(1): 98, 2018 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-30497456

RESUMO

BACKGROUND: Fabrication of porous scaffolds with great biocompatibility and osteoinductivity to promote bone defect healing has attracted extensive attention. METHODS: In a previous study, novel lanthanum phosphate (LaPO4)/chitosan (CS) scaffolds were prepared by distributing 40- to 60-nm LaPO4 nanoparticles throughout plate-like CS films. RESULTS: Interconnected three dimensional (3D) macropores within the scaffolds increased the scaffold osteoconductivity, thereby promoting cell adhesion and bone tissue in-growth. The LaPO4/CS scaffolds showed no obvious toxicity and accelerated bone generation in a rat cranial defect model. Notably, the element La in the scaffolds was found to promote osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) through the Wnt/ß-catenin signalling pathway and induced high expression of the osteogenesis-related genes alkaline phosphatase, osteocalcin and Collagen I (Col-I). Moreover, the LaPO4/CS scaffolds enhanced bone regeneration and collagen fibre deposition in rat critical-sized calvarial defect sites. CONCLUSION: The novel LaPO4/CS scaffolds provide an admirable and promising platform for the repair of bone defects.


Assuntos
Materiais Biocompatíveis/química , Quitosana/química , Lantânio/química , Fosfatos/química , Engenharia Tecidual , Alicerces Teciduais , Animais , Regeneração Óssea , Células-Tronco Mesenquimais/citologia , Osteogênese , Ratos Sprague-Dawley , Engenharia Tecidual/métodos , Alicerces Teciduais/química , beta Catenina/metabolismo
8.
Nanomedicine ; 14(3): 811-822, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29339189

RESUMO

For effectively treating tumor related-bone defects, design and fabrication of multifunctional biomaterials still remain a great challenge. Herein, we firstly fabricated magnetic SrFe12O19 nanoparticles modified-mesoporous bioglass (BG)/chitosan (CS) porous scaffold (MBCS) with excellent bone regeneration and antitumor function. The as-produced magnetic field from MBCS promoted the expression levels of osteogenic-related genes (OCN, COL1, Runx2 and ALP) and the new bone regeneration by activated BMP-2/Smad/Runx2 pathway. Moreover, the SrFe12O19 nanoparticles in MBCS improved the photothermal conversion property. Under the irradiation of near-infrared (NIR) laser, the elevated temperatures of tumors co-cultured with MBCS triggered tumor apoptosis and ablation. As compared with the pure scaffold group, MBCS/NIR group possessed the excellent antitumor efficacy against osteosarcoma via the hyperthermia ablation. Therefore, the multifunctional MBCS with excellent bone regeneration and photothermal therapy functions has a great application for treating the tumor-related bone defects.


Assuntos
Neoplasias Ósseas/terapia , Regeneração Óssea , Hipertermia Induzida , Nanopartículas de Magnetita/administração & dosagem , Osteossarcoma/terapia , Fototerapia , Alicerces Teciduais , Animais , Neoplasias Ósseas/patologia , Proliferação de Células , Humanos , Lasers , Nanopartículas de Magnetita/química , Masculino , Osteossarcoma/patologia , Porosidade , Ratos , Ratos Sprague-Dawley , Células Tumorais Cultivadas
9.
Macromol Rapid Commun ; 38(9)2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28295875

RESUMO

This communication describes a simple and effective method for welding electrospun nanofibers at the cross points to enhance the mechanical properties of their nonwoven mats. The welding is achieved by placing a nonwoven mat of the nanofibers in a capped vial with the vapor of a proper solvent. For polycaprolactone (PCL) nanofibers, the solvent is dichloromethane (DCM). The welding can be managed in a controllable fashion by simply varying the partial pressure of DCM and/or the exposure time. Relative to the pristine nanofiber mat, the mechanical strength of the welded PCL nanofiber mat can be increased by as much as 200%. Meanwhile, such a treatment does not cause any major structural changes, including morphology, fiber diameter, and pore size. This study provides a generic method for improving the mechanical properties of nonwoven nanofiber mats, holding great potential in various applications.


Assuntos
Fenômenos Mecânicos , Nanofibras/química , Nanofibras/normas , Soldagem
11.
Food Res Int ; 191: 114707, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39059958

RESUMO

Citri Reticulatae Pericarpium (CRP) is a traditional herbal and food spice, the flavor and active compounds content of Xinhui CRP improves with aging. To investigate the pattern of microbial community succession during the aging of Xinhui CRP and its correlation with changes in flavor compounds, the high-throughput sequencing, HPLC, and GC-IMS were used to analyze the microbial community, flavonoids, and flavor compounds of five different aging years in this study. The results revealed different dominant microbial communities in Xinhui CRP at different aging time, and unclassified Bacteria were the predominant bacterial genus during 10-15 years of aging. As the aging time increases, the abundance of microbial community decreases and gradually stabilizes. At the fungal genus level, Xeromyces (>99 %) were the dominant genus during the 10-15 years aging time and had a significant correlation with polymethoxyflavones (PMFs), and the concentrations of PMFs increased with the progression of aging years. The GC-IMS results revealed distinctive flavor profiles in Xinhui CRP across different aging years, floral and fruity aromas, such as heptanal, 3-methyl-3-butenol, and 1-butanol, among others, with increasing aging years. A comprehensive correlation analysis further elucidates the close relationship between the core microorganism community and flavor formation in Xinhui CRP (p < 0.05). Notably, Pseudomonas and Escherichia Shigella exhibited significant correlations with beta-pinene and alpha-pinene, whereas Aureobasidium and Sarcopodium were associated with nerol and α-phellandrene (p < 0.05). This study provides new ideas for accelerating the good quality and flavor of Xinhui CRP during the aging process from the perspective of key microorganisms.


Assuntos
Bactérias , Citrus , Microbiota , Citrus/microbiologia , Citrus/química , Bactérias/classificação , Bactérias/metabolismo , Frutas/microbiologia , Frutas/química , Aromatizantes/análise , Paladar , Compostos Orgânicos Voláteis/análise , Flavonoides/análise , Odorantes/análise , Fungos/classificação , Cromatografia Líquida de Alta Pressão , Fatores de Tempo , Monoterpenos Bicíclicos
12.
Int J Biol Macromol ; 267(Pt 2): 131495, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38614180

RESUMO

Konjac glucomannan (KGM) is becoming a very potential food packaging material due to its good film-forming properties and stability. However, KGM film has several shortcomings such as low mechanical strength, strong water absorption, and poor self-antibacterial performance, which limits its application. Therefore, in order to enhance the mechanical and functional properties of KGM film, this study prepared Pickering nanoemulsion loaded with eugenol and added it to the KGM matrix to explore the improvement effect of Pickering nanoemulsion on KGM film properties. Compared to pure KGM film and eugenol directly added film, the mechanical strength of Pickering-KGM film was significantly improved due to the establishment of ample hydrogen bonding interactions between the ß-cyclodextrin inclusion complex system and KGM. Pickering-KGM film had significant antioxidant capacity than pure KGM film and eugenol directly added KGM film (eugenol-KGM film) (~3.21 times better than KGM film, ~0.51 times better than eugenol-KGM film). In terms of antibacterial activity, Pickering-KGM film had good inhibitory effect on Escherichia coli, Staphylococcus aureus, and Candida albicans, and raspberry preservation experiment showed that the shelf life of the Pickering-KGM film could be extended to about 6 days. To sum up, this study developed a novel means to improve the film performance and provide a new insight for the development and application of food packaging film.


Assuntos
Emulsões , Eugenol , Embalagem de Alimentos , Mananas , Eugenol/química , Eugenol/farmacologia , Mananas/química , Emulsões/química , Embalagem de Alimentos/métodos , Antibacterianos/farmacologia , Antibacterianos/química , Antioxidantes/química , Antioxidantes/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Testes de Sensibilidade Microbiana
13.
Food Chem ; 457: 140160, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-38917569

RESUMO

The dynamic combination of aromas and cyclodextrins is an important means to achieve their stability and controllability, and accurately revealing their interaction rules is the key to designing and constructing high-quality aroma nanocarriers. In this study, the inclusion mechanism between alcohol aroma compounds with different structures and ß-cyclodextrin (ß-CD) was studied by combining molecular dynamics simulation and experimental methods. Results showed that the selected alcohol aroma compounds formed inclusion complexes (ICs) with ß-CD in a 1:1 ratio, while alcohol aroma compounds containing cyclic structures were more tightly bound to ß-CD. Van der Waals forces were the primary forces driving the formation and stabilization of the ICs. Cinnamyl alcohol/ß-CD ICs showed the most significant antimicrobial effect and notably prolonged the shelf life of strawberries. This study aimed to provide theoretical support for precisely designing and preparing highly stable flavours and fragrances, as well as expanding their application range.


Assuntos
Fragaria , Odorantes , beta-Ciclodextrinas , Fragaria/química , beta-Ciclodextrinas/química , Odorantes/análise , Conservação de Alimentos/métodos , Álcoois/química , Simulação de Dinâmica Molecular , Aromatizantes/química , Bactérias/efeitos dos fármacos , Bactérias/química
14.
Foods ; 13(5)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38472834

RESUMO

The daylily (Hemerocallis citrina Baroni) flower is a traditional raw food material that is rich in a variety of nutrients. In particular, the content of polysaccharides in daylily is abundant and has been widely used as a functional component in food, cosmetics, medicine, and other industries. However, studies on the structure-effective relationship of daylily flower polysaccharides are still lacking. In view of this, daylily flower polysaccharides were isolated and purified, and their physical and chemical properties, structure, antioxidant activity, and adhesion-promoting effect on probiotics were evaluated. The results showed that a novel water-soluble polysaccharide (DPW) with an average molecular weight (Mw) of 2.224 kDa could be successfully isolated using column chromatography. Monosaccharide composition analysis showed that DPW only comprised glucose and fructose, with a molar ratio of 0.242:0.758. Through methylation and nuclear magnetic resonance (NMR) analysis, it was inferred that DPW belonged to the fructans group with a structure of α-D-Glcp-1→2-ß-D-Fruf-1→(2-ß-D-Fruf-1)n→. Antioxidant analysis showed that DPW showed strong 2-Phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-Oxide (PTIO-scavenging activity with IC50 of 1.54 mg/mL. DPW of 1.25 to 5 mg/mL could significantly increase the adhesion rate of Lactobacillus acidophilu, Lactobacillus casei, Bifidobacterium adolescentis, and Lactobacillus plantarum on Caco-2 cells. Considering the above results, the present study provides a theoretical basis and practical support for the development and application of daylily polysaccharides as a functional active ingredient.

15.
Food Chem ; 444: 138751, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38412567

RESUMO

Previous lipase inhibitors studies mainly focus on the binding between inhibitors and lipase, ignoring the impact of inhibitors on the oil-water interface of lipid droplets. This study aimed to investigate the effect of nobiletin (NBT) from Citri Reticulatae Pericarpium on the oil-water interface properties and lipid digestion. Here, we found that NBT could destroy bile salt (BS)-stabilized lipid droplets and thus inhibited free fatty acid release, owing to the interaction between NBT and BS at the oil-water interface, and reducing the stability of the oil-water interface (the stability index decreased from 91.15 ± 2.6 % to 66.5 ± 3.6 %). Further, the molecular dynamics simulation and isothermal titration calorimetry revealed that NBT could combine with BS at oil-water interface through intermolecular interactions, including hydrogen bonds, Van der Waals force, and steric hindrance. These results suggest that the interfacial instability of NBT mediated BS emulsified oil droplets may be another pathway to inhibit lipid digestion.


Assuntos
Ácidos e Sais Biliares , Flavonas , Lipase , Emulsões/química , Lipase/metabolismo , Ácidos Graxos não Esterificados , Digestão , Água/química
16.
Adv Healthc Mater ; : e2401345, 2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38973206

RESUMO

The limited and unstable absorption of excess exudate is a major challenge during the healing of infected wounds. In this study, a highly stable, multifunctional Janus dressing with unidirectional exudate transfer capacity is fabricated based on a single poly(lactide caprolactone) (PLCL). The success of this method relies on an acid hydrolysis reaction that transforms PLCL fibers from hydrophobic to hydrophilic in situ. The resulting interfacial affinity between the hydrophilic/phobic PLCL fibers endows the Janus structure with excellent unidirectional liquid transfer and high structural stability against repeated stretching, bending, and twisting. Various other functions, including wound status detection, antibacterial, antioxidant, and anti-inflammatory properties, are also integrated into the dressing by incorporating phenol red and epigallocatechin gallate. An in vivo methicillin-resistant Staphylococcus aureus-infected wound model confirms that the Janus dressing, with the capability to remove exudate from the infected site, not only facilitates epithelialization and collagen deposition, but also ensures low inflammation and high angiogenesis, thus reaching an ideal closure rate up to 98.4% on day 14. The simple structure, multiple functions, and easy fabrication of the dressing may offer a promising strategy for treating chronic wounds, rooted in the challenges of bacterial infection, excessive exudate, and persistent inflammation.

17.
Front Nutr ; 10: 1161232, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37032777

RESUMO

ß-Cyclodextrin (ß-CD) can combine with oil and other guest molecules to form amphiphilic inclusion complexes (ICs), which can be adsorbed on the oil-water interface to reduce the interfacial tension and stabilize Pickering emulsions. However, the subtle change of ß-CD in the process of emulsion preparation is easily ignored. In this study, ß-CD and ginger oil (GO) were used to prepare the Pickering emulsion by high-speed shearing homogenization without an exogenous emulsifier. The stability of the emulsion was characterized by microscopic observation, staining analysis, and creaming index (CI). Results showed that the flocculation of the obtained Pickering emulsion was serious, and the surface of the droplets was rough with lamellar particles. In order to elucidate the formation process of the layered particles, the GO/ß-CD ICs were further prepared by ball milling method, and the X-ray diffraction (XRD), scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), and interfacial tension analyses found that ß-CD and GO first formed amphiphilic nanoscale small particles (ICs) through the host-guest interaction, and the formed small particles were further self-assembled into lamellar micron-scale amphiphilic ICs microcrystals. These amphiphilic ICs and microcrystals aggregated at the oil-water interface and finally formed the Pickering emulsion. In this study, by exploring the formation process and evolution of GO/ß-CD self-assembly, the formation process and stabilization mechanism of the ß-CD-stabilized GO Pickering emulsion were clarified preliminarily, with the aim of providing a theoretical basis for the development of high-performance CD-stabilized Pickering emulsions.

18.
J Air Waste Manag Assoc ; 73(11): 853-864, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37751230

RESUMO

Thermal treatment is a mainstream technique to separate plastic components from waste crystalline silicon (c-Si) photovoltaic (PV) modules. In this study, the thermogravimetric analysis (TGA) was conducted for a better understanding of the characteristics of plastic components mainly poly(ethylene-co-vinyl) acetate (EVA) binder and polyfluoroethylene composite membrane (TPT) backsheet in waste c-Si PV panels through thermal treatment at four different heating rates (5-20°C·min-1) under nitrogen and air conditions, respectively. The thermal process of the EVA binder whether in a nitrogen or air atmosphere could be divided into two phases, which were 300-400°C and 400-515°C in nitrogen with the total weight loss reached 99.64%; the two phases in the air were 270-405°C and 405-570°C with the total weight loss was 99.68%. The thermal weight loss of TPT in nitrogen has only one phase occured between 380°C and 520°C, and the weight loss rate is about 83%. There are two weight loss phases in the air atmosphere, which the first phase starts from 265°C to 485°C and the second phase ends at 635°C with a final weight loss reaching 97%. Furthermore, the Kissinger-Akahira-Sunose (KAS) method was chosen to calculate the pyrolysis kinetic parameters. The activation energy for EVA in nitrogen (261.16 kJ·mol-1) was higher than in air (209.04 kJ·mol-1), also the TPT in nitrogen (188.28 kJ·mol-1) higher than in air (172.21 kJ·mol-1). That indicated that the thermal decomposition of EVA binder was accelerated at first phase in nitrogen, but there is little difference in air atmosphere. Moreover, the activation energy of PVF of the TPT backsheet in the first phase was lower than that in the second phase. This study provides the fundamental basis to develop efficient thermal separation for the plastic components EVA and TPT in waste PV panels.Implications: This study mainly aims to explore the thermal separation of plastic components of waste c-Si panels for heating treatment, so that developing an accurate heat treatment approach that is efficient to implement for the separation of secondary raw material i.e., glass and silicon wafer from end-of-life PV panels. Therefore, this research findings have significant implications for providing the basic data support for waste PV panels management recycling standards, specifications, or policy documents.


Assuntos
Nitrogênio , Silício , Humanos , Termogravimetria , Cinética , Redução de Peso
19.
Int J Biol Macromol ; 238: 124066, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-36934822

RESUMO

Feather keratin from waste feather has become an attractive target to replace petroleum-based Poly (vinyl alcohol) sizes due to its easy film-forming ability, excellent adhesive property, biodegradability and low cost. However, poor water-solubility and brittleness of pure keratin films have become the bottlenecks and restricted the application of keratin as sizing agents. Therefore, water-soluble keratin was extracted by the reduction-preservation method and enhanced by saccharides in aqueous system to obtain all-green keratin-based slurry. The results showed that the keratin-based slurry exhibited improved sizing performance in the order of sucrose ≤ glucose ≤ pullulan by the moderate Maillard reaction. Among them, the fabricated pullulan-keratin sizes films had 27.86 %, 2684.08 % and 2911.31 % increment in tensile strength, elongation and work of facture compared with pure keratin sizes films. Besides, the addition of pullulan and subsequently moderate Maillard reaction improved the thermo-tenacity of keratin-based sizes, which was expected to tackle with the brittleness of pure keratin size films. In addition, novel pullulan-keratin sizes had good sizing performance and high desizing efficiency to cotton, cotton/polyester and polyester yarns and fabrics. Successful utilization of pullulan-keratin sizes will bring opportunities for high value utilization of waste feather and promote the green and low-carbon development of textile industry.


Assuntos
Queratinas , Água , Indústria Têxtil , Poliésteres
20.
Carbohydr Polym ; 308: 120661, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36813345

RESUMO

Fragrance finishing of textiles is receiving substantial interest, with aromatherapy being one of the most popular aspects of personal health care. However, the longevity of aroma on textiles and presence after subsequent launderings are major concerns for aromatic textiles directly loaded with essential oils. These drawbacks can be weakened by incorporating essential oil-complexed ß-cyclodextrins (ß-CDs) onto various textiles. This article reviews various preparation methods of aromatic ß-cyclodextrin nano/microcapsules, as well as a wide variety of methods for the preparation of aromatic textiles based on them before and after forming, proposing future trends in preparation processes. The review also covers the complexation of ß-CDs with essential oils, and the application of aromatic textiles based on ß-CD nano/microcapsules. Systematic research on the preparation of aromatic textiles facilitates the realization of green and simple industrialized large-scale production, providing needed application potential in the fields of various functional materials.

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