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1.
Braz. j. biol ; 84: e257070, 2024. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1360228

RESUMO

Nanoparticles (NPs) are insoluble particles with a diameter of fewer than 100 nanometers. Two main methods have been utilized in orthodontic therapy to avoid microbial adherence or enamel demineralization. Certain NPs are included in orthodontic adhesives or acrylic resins (fluorohydroxyapatite, fluorapatite, hydroxyapatite, SiO2, TiO2, silver, nanofillers), and NPs (i.e., a thin layer of nitrogen-doped TiO2 on the bracket surfaces) are coated on the surfaces of orthodontic equipment. Although using NPs in orthodontics may open up modern facilities, prior research looked at antibacterial or physical characteristics for a limited period of time, ranging from one day to several weeks, and the limits of in vitro studies must be understood. The long-term effectiveness of nanotechnology-based orthodontic materials has not yet been conclusively confirmed and needs further study, as well as potential safety concerns (toxic effects) associated with NP size.


Nanopartículas (NPs) são partículas insolúveis com diâmetro inferior a 100 nanômetros. Dois métodos principais têm sido utilizados na terapia ortodôntica para evitar a aderência microbiana ou a desmineralização do esmalte: NPs são incluídas em adesivos ortodônticos ou resinas acrílicas (fluoro-hidroxiapatita, fluorapatita, hidroxiapatita, SiO2, TiO2, prata, nanopreenchimentos) e NPs são revestidas nas superfícies de equipamentos ortodônticos, ou seja, uma camada fina de TiO2 dopado com nitrogênio nas superfícies do braquete. Embora o uso de NPs em ortodontia possa tornar acessível modernos recursos, pesquisas anteriores analisaram as características antibacterianas ou físicas por um período limitado de tempo, variando de 24 horas a várias semanas, por isso devem ser compreendidos os limites dos estudos in vitro. A eficácia de longo prazo de materiais ortodônticos com base em nanotecnologia ainda não foi confirmada de forma conclusiva, o que exige mais estudos, bem como potenciais preocupações de segurança (efeitos tóxicos) associadas ao tamanho da NP.


Assuntos
Ortodontia , Desmineralização , Esmalte Dentário , Nanopartículas , Anti-Infecciosos
2.
Braz. j. biol ; 84: e253555, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1355900

RESUMO

Abstract The aim of the present study is to assess the effects of selenium nanoparticles on the growth, hematology and nutrients digestibility of Labeorohita fingerlings. Fingerlings were fed with seven isocaloric sunflower meal-based diet supplemented with different concentrations of nanoparticles naming T1 to T7 (0, 0.5, 1, 1.5, 2, 2.5, and 3 mg/kg), with 5% wet body weight while chromic oxide was used as an indigestible marker. After experimentation for 90 days T3 treated group (1mg/kg -1Se-nano level) showed the best result in hematological parameters (WBC's 7.97 ×103mm-3, RBC's 2.98 ×106 mm-3 and Platelet count 67), nutrient digestibility (crude protein: 74%, ether extract: 76%, gross energy: 70%) and growth performance (weight gain 13.24 g, weight gain% 198, feed conversion ratio 1.5, survival rate 100%) as compared to the other treatment groups. Specific growth rates were found significantly higher in T5 than in other groups. The present study indicated positive effect of 1 mg/kg Se-nanoparticles on growth advancement, hematological parameters, and nutrients digestibility of L. rohita fingerlings.


Resumo O objetivo do presente estudo é avaliar os efeitos das nanopartículas de selênio no crescimento, hematologia e digestibilidade dos nutrientes de alevinos de Labeo rohita. Os alevinos foram alimentados com sete dietas isocalóricas à base de farinha de girassol suplementada com diferentes concentrações de nanopartículas, nomeando T1 a T7 (0, 0,5, 1, 1,5, 2, 2,5 e 3 mg / kg), com 5% do peso corporal úmido enquanto o óxido crômico foi usado como um marcador indigesto. Após a experimentação por 90 dias, o grupo tratado com T3 (nível 1mg / kg -1Se-nano) mostrou o melhor resultado em parâmetros hematológicos (WBC's 7,97 × 103mm-3, RBC's 2,98 × 106mm-3 e contagem de plaquetas 67), digestibilidade dos nutrientes (proteína bruta: 74%, extrato de éter: 76%, energia bruta: 70%) e desempenho de crescimento (ganho de peso 13,24 g, ganho de peso % 198, taxa de conversão alimentar 1,5, taxa de sobrevivência 100%) em comparação com os outros grupos de tratamento. As taxas de crescimento específicas foram encontradas significativamente mais altas em T5 do que em outros grupos. O presente estudo indicou efeito positivo de 1 mg / kg de nanopartículas de Se no avanço do crescimento, parâmetros hematológicos e digestibilidade de nutrientes de alevinos de L. rohita.


Assuntos
Animais , Nanopartículas , Helianthus , Nutrientes , Suplementos Nutricionais , Dieta , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal
3.
Food Chem ; 399: 134008, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36037693

RESUMO

The Tyndall Effect assay (TEA) has been applied into colorimetric metal ion detection since 2019. However, the TEA-based sensor for pesticide detection has never been reported till now. Herein, a facile fluorescent organic nanoparticle (FON)-based sensor is firstly developed for fluorine-containing pesticide detection through ratiometric fluorescence assay (FLA) and TEA. For FLA, the intensity of the second-order Tyndall scattering peak (STS590nm) and the fluorescence peak of the FON-based sensor would increase and remain unchanged respectively when adding bifenthrin, flufenoxuron, and diflubenzuron. The detection limits were respectively 9.34, 6.91, and 3.60 µg/kg. For TEA, the increased STS590nm intensity displayed a bright and visible light beam. An economical, simple, and portable device was then constructed to visually monitor the analytes. The sensor was successfully used to detect the analytes in teas through FLA and TEA with the recoveries and RSD ranging from 86.27-100.00 %, and 0.00-5.68 %, respectively.


Assuntos
Diflubenzuron , Nanopartículas , Praguicidas , Corantes Fluorescentes , Fluoretos , Flúor , Compostos de Fenilureia , Piretrinas , Chá
4.
Food Chem ; 399: 133955, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36041336

RESUMO

Herbicides atrazine and acetochlor are used in crop production. Because of environmental and health hazards with respective maximum contamination levels of 3 and 20 ng/mL, quantifying these herbicides is important when considering presence in foods and vegetables. We utilized two Pd@Pt nanoparticle-amplified immunoassays, a colorimetric Pd@Pt nanoparticle-linked immunosorbent assay (NLISA) and differential pulse voltammetry (DPV) dependent on catalytic activity of Pd@Pt in a dual-lateral flow immunoassay (dual-LFIA-DPV). We achieved overall recoveries of 88.5-114 % in juice, fruit, and vegetable samples for both immunoassays. The NLISA yielded limits of detection (LODs) of 0.59 and 0.31 µg/kg and the dual-LFIA-DPV 0.27 and 0.51 µg/kg for the two respective species. Results for both immunoassays were validated by high-performance liquid chromatography (HPLC), for all food and drink samples though LODs are compromised when configuring the HPLC for both species with the same chromatogram. We expect Pd@Pt-based immunoassays to prove useful in various fields.


Assuntos
Herbicidas , Nanopartículas , Frutas/química , Herbicidas/análise , Imunoensaio/métodos , Imunoadsorventes/análise , Limite de Detecção , Verduras/química
5.
Food Chem ; 398: 133851, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35963217

RESUMO

Modulating the size and surface charge of nanocarriers provides an efficacious strategy to enhance bioavailability of encapsulated cargos through increased mucus penetration. In this study, mucus-permHeable soy protein nanoparticles (SPNPs) were successfully fabricated via gastrointestinal proteolysis coupled with heating and pH-shifting treatment. Results showed that treatment at 65 °C and 75 °C after proteolysis induced the assembly of α, ά, and ß subunits, forming a relatively loose structure. This facilitated further assembly upon pH-shifting, forming smaller-sized and less electronegative nanoparticles, which showed enhanced mucus permeability. However, treatment at 85 °C and 95 °C promoted stronger hydrophobic interactions and induced disulfide bond cross-linking between B and ß subunits, forming compact macro-aggregates with high ß-sheet structure. These larger-sized aggregates were less influenced by pH-shifting treatment, demonstrating limited mucus diffusion. This study provides a potential alternative to fabricate mucus-permeable nanoparticles, and established a relationship between protein subunit assembly behavior and its mucus permeability.


Assuntos
Nanopartículas , Proteínas de Soja , Portadores de Fármacos/química , Concentração de Íons de Hidrogênio , Hidrólise , Muco/metabolismo , Nanopartículas/química , Proteínas de Soja/química
6.
Food Chem ; 398: 133862, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35963220

RESUMO

In this study, co-assembled protein-polysaccharide complexes (ZCs) were prepared by fixing zein nanoparticles at the fibrillar carboxymethyl cellulose (CMC) by pH-driven anti-solvent precipitation. The complexation boosted the dispersity of zein from 17.3% to 88.6%. Scanning electron microscopy and atomic force microscopy confirmed the formation of network structures where the fibrous polysaccharides inserted into the interval of granular proteins. Circular dichroism spectrum, fluorescence spectrum, and X-ray diffraction verified the electrostatic interaction pattern between zein and CMC. Besides, the ZCs presented favorable amphiphilic properties, and the electrostatic interaction between zein and CMC can be fine-tuned by the substitution degree (DS) of carboxymethyl in CMC. Therefore, the Pickering emulsions stabilized by ZCs had controllable size and long-term stability using DS as a stimulus. Our study offers a novel strategy developing bio-based materials as novel stabilizers of Pickering emulsions.


Assuntos
Nanopartículas , Zeína , Carboximetilcelulose Sódica/química , Emulsões/química , Nanopartículas/química , Tamanho da Partícula , Zeína/química
7.
Food Chem ; 398: 133878, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35964559

RESUMO

In this study, novel bioavailable selenium nanoparticles with controllable particle size and low toxicity were developed. With selenium modified zein nanoparticles (zein NPs) in-situ, dispersed nano-selenium particles with different structure were formed simultaneously. The particle size, zeta potential, morphology and binding mechanism of synthesized zein-selenium nanoparticles (zein-Se NPs) were systematically discussed. Selenium was considered to be combined with OH and -CO-NH- groups of zein. The selenium in the complex particles presented an amorphous structure with zero valence. The cytotoxicity of zein-Se NPs was significantly lower than that of sodium selenite, even exhibited a growth-promoting effect on normal liver cells (L-02), and were proven to be orally absorbed by organisms in vivo experiments. The difference in particle structure had certain effects on cytotoxicity and oral targeting. The complex particles obtained by this method were anticipated be further used as food fortifiers or medicines.


Assuntos
Nanopartículas , Selênio , Zeína , Disponibilidade Biológica , Tamanho Celular , Nanopartículas/química , Tamanho da Partícula , Selênio/química , Zeína/química
8.
Food Chem ; 399: 133952, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35998492

RESUMO

Although excessive pharmaceutical activities of curcumin have been reported, the poor solubility, low stability and low bioavailability greatly limited its application. In this study, the interaction between protein Z (PZ) and curcumin, and the effects of PZ on the stability and bioavailability of curcumin were investigated. Fluorescence quenching results indicated that curcumin molecule binds PZ with a stoichiometry of 4:1, and the binding affinity is stronger than other reported protein carriers. Molecular dynamics simulation results suggested that curcumin binds in the hydrophobic region of PZ, and the interaction was maintained mainly by hydrogen-bond (Pro-287, Asn-340 and Tyr-234). PZ-curcumin complex possessed better encapsulation efficiency (64.10 %) and loading capacity (5.49 µg/mg) for curcumin. In addition, binding with PZ not only improved the thermal, light and digestive stability of curcumin significantly, but lowered its toxic effect on Caco-2 cells and improved relative bioavailability (305 %) compared with that of curcumin only.


Assuntos
Curcumina , Hordeum , Nanopartículas , Disponibilidade Biológica , Proteínas Sanguíneas , Células CACO-2 , Curcumina/química , Portadores de Fármacos/química , Hordeum/metabolismo , Humanos , Nanopartículas/química , Solubilidade
9.
Food Chem ; 399: 133970, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35998499

RESUMO

Lateral flow immunoassays (LFIAs) are routine methods for rapid foodborne pollutants screening, with detection limits that are closely associated with the label probes used. The exploitation of high performance and robust probe is highly desirable, and remains a great challenge. Herein, we reported an emerging fluorescent nanobeads i.e. carbon-dots (CD) covalently incorporated mesoporous silicon nanoparticles (CD-MSNs) for LFIAs. CD-MSNs revealed brighter fluorescence, larger particle size and more modification sites in comparison with those of single CD. After bio-functionalisation, CD-MSNs probes were introduced to construct LFIA test strips, and designed for ultrasensitive detection of aflatoxin B1 (AFB1) and Staphylococcus aureus (S. aureus), two representative foodborne pollutants, based on the competitive and sandwich models, respectively. Very competitive quantitative detection limits i.e. 0.05 ng/mL and 102 cfu/mL were correspondingly obtained. Additionally, the test strips were successfully applied to rapidly and accurately screen AFB1 and S. aureus in food samples, highlighting their practicality.


Assuntos
Poluentes Ambientais , Nanopartículas , Aflatoxina B1/análise , Carbono , Corantes Fluorescentes , Imunoensaio/métodos , Limite de Detecção , Silício , Staphylococcus aureus
10.
Methods Mol Biol ; 2566: 313-320, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36152262

RESUMO

Investigating at transmission electron microscopy the intracellular trafficking of hyaluronic acid-based nanoparticles remains a challenge due to their intrinsic weak electron density. Here we describe a simple protocol to stain hyaluronic acid that allows visualization of hyaluronic acid-based nanoparticles inside cells at both light and electron microscopy. By applying the critical-electrolyte-concentration Alcian blue method, these nanoparticles were observed as blue dots at bright-field microscopy or filled with fine electron dense precipitates at transmission electron microscopy.


Assuntos
Ácido Hialurônico , Nanopartículas , Azul Alciano , Corantes , Coloração e Rotulagem
11.
Methods Mol Biol ; 2566: 321-332, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36152263

RESUMO

Iron deposits in cells and tissues can be detected by ex vivo histological examination through the Prussian blue (PB) staining. This practical, inexpensive, and highly sensitive technique involves the treatment of fixed tissue sections and cells with acid solutions of ferrocyanides that combine with ferric ion forming a bright blue pigment (i.e., ferric ferrocyanide). The staining can be applied to visualize iron oxide nanoparticles (IONPs), versatile magnetic nanosystems that are used in various biomedical applications and whose localization is usually required at a higher resolution than that enabled by in vivo tracking techniques.


Assuntos
Nanopartículas de Magnetita , Nanopartículas , Compostos Férricos , Ferrocianetos , Ferro , Nanopartículas Magnéticas de Óxido de Ferro , Imageamento por Ressonância Magnética , Coloração e Rotulagem
12.
Methods Mol Biol ; 2566: 333-343, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36152264

RESUMO

Visualizing nanoparticles made of organic material (e.g., polysaccharides, proteins, non-osmiophilic lipids) inside cells and tissues at transmission electron microscopy is a difficult task due to the intrinsic weak electron density of these nanoconstructs, which makes them hardly distinguishable in the biological environment. We describe here a simple protocol to apply photooxidation to fluorescently labeled nanoparticles administered to cultured cells in vitro. The conversion of the fluorescent signal into a granular electron-dense reaction product through light irradiation in the presence of diaminobenzidine makes the nanoparticles clearly visible at the ultrastructural level. Our procedure proved to be reliable with various fluorophores and may be applied to any cell type.


Assuntos
Nanopartículas , 3,3'-Diaminobenzidina/química , Células Cultivadas , Corantes Fluorescentes/química , Lipídeos , Microscopia Eletrônica de Transmissão , Nanopartículas/química
13.
Food Chem ; 399: 133964, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36029675

RESUMO

We employed dithiothreitol (DTT) to reassemble soy lipophilic protein (LP) and increased its solubility for encapsulating resveratrol (Res); we subsequently added hydroxypropyl methylcellulose (HPMC) to further stabilize Res. Physicochemical characterization, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and spectral analysis revealed that DTT triggered the breakage and reassembly of the disulfide bond. Consequently, the solubility of LP increased from 38.64 % to 71.49 %, and the number of free sulfhydryl groups increased to 7.84 mol·g-1. Furthermore, the encapsulation efficiency and structure of reassembled LP nanoparticles loaded with Res were found to be closely related to the DTT concentration used for induction. When HPMC was added, the LP-Res complex demonstrated spontaneous self-assembly, and the pH and temperature stability of the Res in the nanoparticles improved. An in vitro digestion simulation revealed that the reassembled LP was an efficient carrier for Res delivery. Particularly, HPMC improved the bioavailability and sustained release of Res.


Assuntos
Ditiotreitol , Derivados da Hipromelose , Nanopartículas , Resveratrol , Proteínas de Soja , Excipientes , Derivados da Hipromelose/química , Nanopartículas/química , Solubilidade , Proteínas de Soja/química , Soja
14.
Food Chem ; 400: 133873, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36087477

RESUMO

To overcome the low production efficiency of Pickering emulsion stabilizers prepared from starch, alcohol precipitation and surface modification were applied in this study. Spherical starch nanoparticles (StNPs) (247.90 ± 1.96 nm) were prepared through nanoprecipitation. The StNPs were surface-esterified to produce starch nanoparticle acetate (StNPAc), and the physicochemical changes of the products were investigated. The contact angle (>89.56° ± 0.56°) of StNPAc (degree of substitution, 0.53) was maintained for over 30 min. The results showed that the hydrophobicity of the StNPs was improved by shielding the surface hydroxyl groups via acetylation. StNPAc was also used to produce emulsions for further evaluation of their feasibility as Pickering emulsifiers. Oil-in-water (3:7, v/v) emulsions containing 1.5 wt% StNPAc were stabilized for over 35 days without creaming. Thus, StNPAc exhibited better emulsifying capacity and storage stability than StNPs. Therefore, hydrophobic starch nanoparticles obtained by acetylation are promising stabilizers for surfactant-free Pickering emulsions.


Assuntos
Nanopartículas , Amido , Acetatos , Emulsões/química , Excipientes , Nanopartículas/química , Tamanho da Partícula , Amido/química , Água/química
15.
Med Res Rev ; 42(2): 800-849, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34693555

RESUMO

Nontoxic materials with natural origin are promising materials in the designing and preparation of the new drug delivery systems (DDSs). Today's, citric acid (CA) has attracted a great deal of attention because of its special features; green nature, biocompatibility, low price, biodegradability, and commercially available property. So, CA has been employed in the preparation of the various platforms to induce a suitable property on their structure. Recently, several research groups investigated the CA-based platforms in different forms like tablets, dendrimers, hyperbranched polymers, (co)polymer, hydrogels, and nanoparticles as efficient DDSs. By considering an increasing amount of published articles in this field, for the first time, in this review, an overview of the published works regarding CA applications in the design of various DDSs is presented with a detailed and insightful discussion.


Assuntos
Ácido Cítrico , Nanopartículas , Sistemas de Liberação de Medicamentos , Humanos , Hidrogéis , Polímeros
16.
Small ; 18(10): e2105880, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34989480

RESUMO

Glyconanoparticles (GNPs) made by self-assembly of carbohydrate-based polystyrene-block-ß-cyclodextrin copolymer are used as a building block for the design of nanostructured biomaterials of electrode. The firm immobilization of GNPs is carried out on electrochemically generated polymer, poly(pyrrole-adamantane), and copolymer, poly(pyrrole-adamantane)/poly(pyrrole-lactobionamide) via host-guest interactions between adamantane and ß-cyclodextrin. The ability of GNPs for the specific anchoring of biological macromolecules is investigated using glucose oxidase enzyme modified by adamantane groups as a protein model (GOx-Ad). The immobilization of GOx-Ad is carried out by incubation of an aqueous enzyme solution on a coating of GNPs adsorbed on a platinum electrode. The presence of immobilized GOx-Ad is evaluated in aqueous glucose solution by potentiostating the underlying platinum electrode at 0.7 V/SCE for the electro-oxidation of H2 O2 generated by the enzyme. The analytical performance of the bioelectrodes for the detection of glucose is compared to control electrodes prepared without GNPs or without electropolymerized films. The better permeability of copolymer compared to polymer and the possibility to elaborate two alternating layers of GNPs and GOx-Ad are clearly observed. The best amperometric response is recorded with a multilayered bioelectrode displaying a wide linear range linear range of the calibration curve: 68 µmol L-1 to 0.1 mol L-1 .


Assuntos
Técnicas Biossensoriais , Nanopartículas , beta-Ciclodextrinas , Eletrodos , Enzimas Imobilizadas/química , Glucose/química , Glucose Oxidase/química , Nanopartículas/química , Pirróis/química , beta-Ciclodextrinas/química
17.
Nanotechnology ; 33(23)2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35193121

RESUMO

We combined phosphoinositol-3-kinin inhibitor IPI-549 and photodynamic Chlorin e6 (Ce6) on carboxymethyl chitosan to develop a novel drug delivery nanoparticle (NP) system (Ce6/CMCS-DSP-IPI549) and evaluate its glutathione (GSH) sensitivity and targeting ability for breast cancer treatment. The NPs were spherical with a uniform size of 218.8 nm, a stable structure over 7 days. The maximum encapsulation efficiency was 64.42%, and NPs drug loading was 8.05%. The NPs released drugs within tumor cells due to their high GSH concentration, while they maintained structural integrity in normal cells, which have low GSH concentration. The cumulative release rates of IPI-549 and Ce6 at 108 h were 70.67% and 40.35% (at GSH 10 mM) and 8.11% and 2.71% (at GSH 2µM), respectively. The NPs showed a strong inhibitory effect on 4T1 cells yet did not affect human umbilical vein endothelial cells (HUVECs). After irradiation by a 660 nm infrared laser for 72 h, the survival rate of 4T1 cells was 15.51%. Cellular uptake studies indicated that the NPs could accurately release drugs into tumor cells. In addition, the NPs had a good photodynamic effect and promoted the release of reactive oxygen species to damage tumor cells. Overall, the combination therapy of IPI-549 and Ce6 is safe and effective, and may provide a new avenue for the treatment of breast cancer.


Assuntos
Neoplasias da Mama , Clorofilídeos , Nanopartículas , Fotoquimioterapia , Porfirinas , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Clorofilídeos/uso terapêutico , Células Endoteliais/patologia , Feminino , Glutationa , Humanos , Isoquinolinas , Nanopartículas/química , Fármacos Fotossensibilizantes , Porfirinas/química , Pirazóis , Pirimidinas
18.
Biomed Res Int ; 2022: 5152911, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36093408

RESUMO

Polyurethane, as a rubber material, can relieve the load on the ground and provide seismic design for the venue, which is of great significance for sports venues. In order to improve the seismic resistance and abrasion resistance of materials for sports fields and reduce accidents in sports, this article has carried out research on the polyurethane elastomer layered nanocomposites for sports fields and their preparation. Today's world is a challenging era of science and technology. The fields of biotechnology, information, medicine, energy, environment, and national defense and security are closely related to the development of high tech, and the requirements for materials are becoming increasingly diversified. Polymer nanocomposite coating has the dual characteristics of organic and inorganic components. It not only retains the advantages of a polymer but also endows it with versatility. It meets the current application needs. It is a hot spot in today's research. Among them, there are two major problems in the composite process of nanomaterials and polymers: dispersion and compatibility. How to improve the dispersion of nanoparticles and enhance the compatibility between nanoparticles and polymers is an urgent problem to be solved. In the method part, this article introduces a small amount of polyurethane and polyurethane elastomers formed after polyurethane modification and introduces layered compounds and nanocomposites and introduces several models involved in nanomaterials in terms of algorithms. In the analysis part, this paper conducts a comprehensive analysis of the hard segment mass fraction, mechanical properties, thermal decomposition behavior, degradation mechanism, and dynamic mechanical properties. With the increase of GO content, the tensile strength increases significantly and the elongation at break becomes smaller and smaller. When the GO content increases from 0% to 2%, the tensile properties of the WPU film increase from 2.6 MPa to 7.9 MPa and the fracture of the elongation decreased from 201.7% to 62.8%. This shows that the increase in GO content will make the composite material harder and brittle. It can be seen from the experimental results that the preparation of the polyurethane elastomer layered nanocomposite material designed in this paper has a good application effect on sports venues.


Assuntos
Nanocompostos , Nanopartículas , Elastômeros , Polímeros , Poliuretanos
19.
Int J Nanomedicine ; 17: 3793-3807, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36072958

RESUMO

Purpose: Forming a compact biological seal between the gingiva and the implant interface around the percutaneous parts of an implant is one of the key issues in preventing peri-implantitis. Methods: In this study, since microRNA-21 (miR-21) has been approved to promote fibroblast proliferation and collagen formation in skin fibrosis, we prepared miR-21-loaded chitosan (CS)/tripolyphosphate (TPP)/hyaluronic acid (HA) nanoparticles (CTH NPs) and cross-linked them to smooth Ti surfaces with 0.2% gel solution for reverse transfection, after which isolated human gingival fibroblasts were cultured on the miR-21-functionalized Ti substrates. Results: An optimal CS:TPP:HA ratio (1:0.15:0.1) and N/P ratio (20:1) were chosen to produce appropriate nanoparticles. Finally, the CTH/miR-21 nanoparticle-coated smooth Ti surfaces demonstrated increased fibroblast adhesion, proliferation and expression of extracellular matrix-related genes along with similar cytotoxicity and cell spreading on the miR-21-functionalized Ti surface and the unmodified smooth Ti surface. Conclusion: The chitosan-based nanoparticles might be an efficient nonviral miRNA vector to form a stable biological seal in percutaneous areas of Ti for clinical use.


Assuntos
Quitosana , MicroRNAs , Nanopartículas , Fibroblastos , Gengiva/metabolismo , Humanos , Ácido Hialurônico/farmacologia , MicroRNAs/genética , MicroRNAs/metabolismo , Propriedades de Superfície , Titânio/farmacologia
20.
Int J Nanomedicine ; 17: 3841-3851, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36072960

RESUMO

Introduction: Transdermal drug delivery provides a desirable alternative method of penetrating the skin for psoriasis treatment, by virtue of its ability to dampen the overactivation of immune cells and inflammation, while attenuating the detrimental effects of systemic administration. Lymph nodes (LNs), as a critical organ of the lymphatic and the acquired immune system, are suitable sites for drug homing to suppress the immune cells. Methods: In this context, we developed a microneedle (MN) patch that delivers nanodrugs locally to LNs for improving the antipsoriatic treatment. In this study, human serum albumin nanoparticles carrying methotrexate (HM) were synthesized and loaded into hyaluronic acid (HA)-based microneedles (HM/MN). Results: The patch showed an excellent ability to pierce the skin, which enhanced drug delivery. In a mouse model of psoriasis, the HM/MN patch significantly prevented the erythema with decreased skin thickness, thus inhibiting the progression of psoriasis. Further analysis for immune cells in LNs, the percent of dendritic cells (DC) and T cells reduced after the local treatment with HM/MN. Notably, the feasibility of targeted delivery of methotrexate to LNs using nanoparticles was verified by detecting increased accumulation of methotrexate in LNs. In addition, the HM/MN patch pronouncedly decreased the levels of tumor necrosis factor α and interleukin 6 in the skin. Conclusion: The results suggested the high efficacy of using the HM/MN patch to treat psoriasis, and provided new insight into the mechanism of the transdermal drug delivery system.


Assuntos
Fármacos Dermatológicos , Nanopartículas , Psoríase , Albuminas , Animais , Sistemas de Liberação de Medicamentos , Humanos , Metotrexato/farmacologia , Camundongos , Psoríase/tratamento farmacológico
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