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1.
Int J Nanomedicine ; 14: 5073-5085, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31371948

RESUMO

Purpose: To potentiate the anticancer activity of curcumin (CUR) by improving its cell penetration potentials through formulating it into nanostructured lipid carriers (NLCs) and using the prepared NLCs in photodynamic therapy. Methods: A 3×4 factorial design was used to obtain 12 CUR-NLCs using two factors on different levels: (1) the solid lipid type at four levels and (2) the solid to liquid lipid ratio at three levels. Olive oil, Tween 80 and lecithin were chosen as liquid lipid, surfactant and co-surfactant, respectively. CUR-NLCs prepared by high shear hot homogenization method were evaluated by determination of particle size (PS), polydispersity index, zeta potential (ZP), entrapment efficiency percent, drug loading percent and in vitro drug release. Optimization was based on the evaluation results using response surface modeling (RSM). Optimized formulae were tested for their in vitro release pattern and for dark and photo-cytotoxic anticancer activity on breast cancer cell line in comparison to free CUR. Results: Evaluation tests showed the appropriateness of NLCs prepared from glyceryl monooleate and Geleol™ helped choosing two optimized formulae, PE3 and GE3. PE3 (prepared using glyceryl monooleate) showed enhanced release rates compared to GE3 (prepared from Geleol) and superior cytotoxic anticancer activity compared to both GE3 and free CUR under both light and dark conditions. The small mean PS, spherical shape as well as the negative ZP enhanced the internalization of the NLCs within cells. Modulation and inhibition of P-glycoprotein expression by glyceryl monooleate synergized the cytotoxic activity of CUR. Conclusion: CUR loading in NLCs enhanced its cell penetration and cytotoxic anticancer properties both in dark and in light conditions.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Curcumina/uso terapêutico , Portadores de Fármacos/química , Lipídeos/química , Nanoestruturas/química , Ácidos Oleicos/química , Azeite de Oliva/química , Fotoquimioterapia , Sobrevivência Celular/efeitos dos fármacos , Curcumina/farmacologia , Liberação Controlada de Fármacos , Feminino , Humanos , Células MCF-7 , Nanoestruturas/ultraestrutura , Tamanho da Partícula , Eletricidade Estática
2.
Chem Soc Rev ; 48(11): 2891-2912, 2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-31120049

RESUMO

The emergence of novel two-dimensional (2D) monoelemental materials (Xenes) has shown remarkable potential for their applications in different fields of technology, as well as addressing new discoveries in fundamental science. Xenes (e.g., borophene, silicene, germanene, stanene, phosphorene, arsenene, antimonene, bismuthene, and tellurene) are of particular interest because they are the most chemically tractable materials for synthetic exploration. Owing to their excellent physical, chemical, electronic and optical properties, Xenes have been regarded as promising agents for biosensors, bioimaging, therapeutic delivery, and theranostics, as well as in several other new bio-applications. In this tutorial review, we summarize their general properties including the classification of Xenes according to their bulk properties. The synthetic and modification methods of Xenes are also presented. Furthermore, the representative Xene nanoplatforms for various biomedical applications are highlighted. Finally, research progress, challenges, and perspectives for the future development of Xenes in biomedicines are discussed.


Assuntos
Materiais Biocompatíveis/química , Nanoestruturas/química , Animais , Materiais Biocompatíveis/uso terapêutico , Técnicas Biossensoriais/métodos , Humanos , Modelos Moleculares , Nanoestruturas/uso terapêutico , Nanoestruturas/ultraestrutura , Nanotecnologia/métodos , Imagem Óptica/métodos , Nanomedicina Teranóstica/métodos
3.
Nat Protoc ; 14(6): 1772-1802, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31101905

RESUMO

Membrane curvatures are involved in essential cellular processes, such as endocytosis and exocytosis, in which they are believed to act as microdomains for protein interactions and intracellular signaling. These membrane curvatures appear and disappear dynamically, and their locations are difficult or impossible to predict. In addition, the size of these curvatures is usually below the diffraction limit of visible light, making it impossible to resolve their values using live-cell imaging. Therefore, precise manipulation of membrane curvature is important to understanding how membrane curvature is involved in intracellular processes. Recent studies show that membrane curvatures can be induced by surface topography when cells are in direct contact with engineered substrates. Here, we present detailed procedures for using nanoscale structures to manipulate membrane curvatures and probe curvature-induced phenomena in live cells. We first describe detailed procedures for the design of nanoscale structures and their fabrication using electron-beam (E-beam) lithography. The fabrication process takes 2 d, but the resultant chips can be cleaned and reused repeatedly over the course of 2 years. Then we describe how to use these nanostructures to manipulate local membrane curvatures and probe intracellular protein responses, discussing surface coating, cell plating, and fluorescence imaging in detail. Finally, we describe a procedure to characterize the nanostructure-cell membrane interface using focused ion beam and scanning electron microscopy (FIB-SEM). Nanotopography-based methods can induce stable membrane curvatures with well-defined curvature values and locations in live cells, which enables the generation of a library of curvatures for probing curvature-related intracellular processes.


Assuntos
Técnicas de Cultura de Células/instrumentação , Membrana Celular/metabolismo , Micromanipulação/instrumentação , Nanoestruturas , Animais , Células COS , Comunicação Celular , Linhagem Celular , Membrana Celular/ultraestrutura , Cercopithecus aethiops , Endocitose , Desenho de Equipamento , Humanos , Camundongos , Microscopia Eletrônica de Varredura , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Imagem Óptica , Proteínas/metabolismo , Propriedades de Superfície
4.
Bioelectrochemistry ; 129: 79-89, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31125924

RESUMO

When implantable recording devices for brain or neural electrical activity are designed, the number of available materials for electrodes is quite limited. The material must be biocompatible with respect to ISO10993, its electrochemical properties must remain stable and the response of cells or tissues can be mitigated, especially on the glial scar. This involves electrode characterization pre- implantation and impedance spectroscopy during chronic implantation, in order to evaluate both electrode properties and performance. This study was aimed at a comparison of the long-term behavior of a nanostructured boron-doped diamond (BDD) with a nanostructured Platinum Iridium (PtIr) electrode. Firstly, a batch of cortical grids with bare and modified contacts (2 mm in diameter) was engineered for implantation. Secondly a miniature swine model was developed. This study highlighted the predominant role of electrode surface roughness on the quality of recordings. Rough PtIr contacts and BDD coated ones showed comparable behavior after three-month implantation with a slight increase of the modulus of the impedance and a tissue capsule. Nevertheless, immunohistochemistry analysis did not exhibit either a toxic or irritation reaction. With regard to biocompatibility, promising long term results are shown for both materials.


Assuntos
Materiais Biocompatíveis/química , Boro/química , Diamante/química , Eletrodos Implantados , Nanoestruturas/química , Animais , Materiais Biocompatíveis/efeitos adversos , Boro/efeitos adversos , Encéfalo/ultraestrutura , Diamante/efeitos adversos , Espectroscopia Dielétrica , Técnicas Eletroquímicas , Eletrodos Implantados/efeitos adversos , Proteína Glial Fibrilar Ácida/análise , Nanoestruturas/efeitos adversos , Nanoestruturas/ultraestrutura , Suínos , Porco Miniatura
5.
Int J Nanomedicine ; 14: 2301-2325, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31114188

RESUMO

Antimicrobial agents have been widely investigated for protecting against microbial infections in modern health. Drug-related limitations, poor bioavailability, toxicity to mammalian cells, and frequent bacteria drug resistance are major challenges faced when exploited in nanomedicine forms. Specific attention has been paid to control nanomaterial-based infection against numerous challenging pathogens in addition to improved drug delivery, targeting, and pharmacokinetic (PK) profiles, and thus, efficient antimicrobials have been fabricated using diverse components (metals, metal oxides, synthetic and semisynthetic polymers, natural or biodegradable polymers, etc). The present review covers several nanocarriers delivered through various routes of administration, highlighting major findings to control microbial infection as compared to using the free drug. Results over the past decade support the consistent development of various nanomedicines capable of improving biological significance and therapeutic benefits against an array of microbial strains. Depending on the intended application of nanomedicine, infection control will be challenged by various factors such as weighing the risk-benefits in healthcare settings, nanomaterial-induced (eco)toxicological hazards, frequent development of antibiotic resistance, scarcity of in vivo toxicity data, and a poor understanding of microbial interactions with nanomedicine at the molecular level. This review summarizes well-established informative data for nanomaterials used for infection control and safety concerns of nanomedicines to healthcare sectors followed by the significance of a unique "safe-by-design" approach.


Assuntos
Controle de Infecções , Nanomedicina/métodos , Animais , Anti-Infecciosos/farmacologia , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Humanos , Nanoestruturas/química , Nanoestruturas/ultraestrutura
6.
Chem Commun (Camb) ; 55(41): 5817-5820, 2019 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-31041939

RESUMO

A novel Au-Se nanoprobe with remarkable anti-interference ability for glutathione was developed for real-time in situ monitoring of the upstream and downstream regulatory relationship between uPA and MMP-9 proteins in the pathway.


Assuntos
Ouro/química , Metaloproteinase 9 da Matriz/análise , Nanoestruturas/química , Neoplasias/diagnóstico por imagem , Imagem Óptica/métodos , Selênio/química , Ativador de Plasminogênio Tipo Uroquinase/análise , Glutationa/química , Humanos , Células MCF-7 , Nanoestruturas/ultraestrutura , Neoplasias/enzimologia
7.
Chem Asian J ; 14(13): 2193-2202, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31125182

RESUMO

DNA nanotechnology has been employed in the construction of self-assembled nano-biomaterials with uniform size and shape for various biological applications, such as bioimaging, diagnosis, or therapeutics. Herein, recent successful efforts to utilize multifunctional DNA origami nanoplatforms as drug-delivery vehicles are reviewed. Diagnostic and therapeutic strategies based on gold nanorods, chemotherapeutic drugs, cytosine-phosphate-guanine, functional proteins, gene drugs, and their combinations for optoacoustic imaging, photothermal therapy, chemotherapy, immunological therapy, gene therapy, and coagulation-based therapy are summarized. The challenges and opportunities for DNA-based nanocarriers for biological applications are also discussed.


Assuntos
DNA/química , Portadores de Fármacos/química , Nanoestruturas/química , Nanotecnologia/métodos , Animais , Sistemas de Liberação de Medicamentos/métodos , Humanos , Nanoestruturas/ultraestrutura , Oligodesoxirribonucleotídeos/administração & dosagem , Preparações Farmacêuticas/administração & dosagem , Proteínas/administração & dosagem
8.
Int J Nanomedicine ; 14: 2267-2280, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31015758

RESUMO

Background: Gypenosides (GPS) have been used as traditional medicine for centuries with various pharmacological effects. However, its therapeutic effects were restricted owing to the poor lipid and water solubility and low absorption. This study aimed to develop nanostructured lipid carriers (NLCs) containing a bile salt formulation (sodium glycocholate, SGC) for GPS, and to evaluate the potential of the GPS-SGC-NLCs as an oral delivery system. Methods: The preparation of GPS-SGC-NLCs was investigated using a single-factor test and a central composite design of response surface methodology. In vitro release and pharmacokinetics studies were used to evaluate the dissolution and bioavailability of GPS. Furthermore, In vivo imaging and in situ intestinal perfusion studies were performed to investigate the absorption of the preparations in the gastrointestinal tract. Results: The optimised formulation yielded nanoparticles with an approximate diameter of 146.7 nm, polydispersity of 0.137, zeta potential of -56.0 mV, entrapment efficiency of 74.22% and drug loading of 4.89%. An in vitro dissolution analysis revealed the sustained release of contents from GPS-SGC-NLCs over 48 h with 56.4% of the drug released. A pharmacokinetic analysis revealed an 8.5-fold increase of bioavailability of the GPS-SGC-NLCs compared with GPS powder. In vivo imaging and in situ intestinal perfusion studies showed that SGC-NLCs could significantly increase the absorption of GPS in intestinal tract. In vitro cytotoxicity evaluated using Caco-2 cells demonstrated that GPS-SGC-NLCs decrease the cytotoxicity of the drug. Conclusion: The SGC-NLC formulation can significantly improve the absorption of GPS, which provides an effective approach for enhancing the oral absorption of drugs.


Assuntos
Ácidos e Sais Biliares/química , Portadores de Fármacos/química , Composição de Medicamentos , Sistemas de Liberação de Medicamentos/métodos , Lipídeos/química , Nanoestruturas/química , Administração Oral , Animais , Células CACO-2 , Varredura Diferencial de Calorimetria , Morte Celular/efeitos dos fármacos , Gynostemma , Humanos , Intestinos/diagnóstico por imagem , Lipídeos/administração & dosagem , Masculino , Nanoestruturas/administração & dosagem , Nanoestruturas/ultraestrutura , Imagem Óptica , Tamanho da Partícula , Perfusão , Extratos Vegetais/administração & dosagem , Extratos Vegetais/sangue , Extratos Vegetais/farmacocinética , Ratos Sprague-Dawley , Ratos Wistar , Eletricidade Estática , Fatores de Tempo , Difração de Raios X
9.
Biosens Bioelectron ; 134: 83-89, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30959392

RESUMO

Biosensors that incorporate nanomaterials and nanofabrication techniques enable molecular detection of chemical and biological macromolecules with a high degree of specificity and ultrasensitivity. Here, we present a novel fabrication process that yields a nanostructure capable of detecting biological macromolecules. The extended core nanocoax (ECC) structure builds on a previously reported nanocoaxial-based sensor. The fabrication of the device incorporates an extended inner pillar, with controllable extension above the annulus and into the surrounding solution. This new design eliminates structural constraints inherent in the original nanocoax architecture. We also provide results demonstrating improvement in biosensing capability. Specifically, we show the capability of the new architecture to detect the B subunit of the Vibrio cholerae toxin at improved sensitivity (100 pg/ml) in comparison to optical enzyme-linked immunosorbant assay (1 ng/ml) and previously reported coaxial nanostructures (2 ng/ml).


Assuntos
Técnicas Biossensoriais/instrumentação , Toxina da Cólera/análise , Técnicas Eletroquímicas/instrumentação , Ensaio de Imunoadsorção Enzimática/instrumentação , Dispositivos Lab-On-A-Chip , Nanoestruturas/ultraestrutura , Proteínas de Bactérias/química , Cólera/microbiologia , Eletrodos , Desenho de Equipamento , Proteínas Imobilizadas/química , Nanoestruturas/química , Compostos de Sulfidrila/química , Vibrio cholerae/isolamento & purificação
10.
BMC Evol Biol ; 19(1): 91, 2019 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-30991958

RESUMO

BACKGROUND: Many species of snakes exhibit epidermal surface nanostructures that form complex motifs conferring self-cleaning properties, and sometimes structural iridescence, to their skin. RESULTS: Using confocal microscopy, we show that these specialised cells can be greatly elongated along their left-right axis and that different types of nanostructures are generated by cell borders and cell surface. To characterise the complexity and diversity of these surface gratings, we analysed scanning electron microscopy images of skin sheds from 353 species spanning 19 of the 26 families of snakes and characterised the observed nanostructures with four characters. The full character matrix, as well as one representative SEM image of each of the corresponding species, is available as a MySQL relational database at https://snake-nanogratings.lanevol.org . We then performed continuous-time Markov phylogenetic mapping on the snake phylogeny, providing an evolutionary dynamical estimate for the different types of nanostructures. These analyses suggest that the presence of cell border digitations is the ancestral state for snake skin nanostructures which was subsequently and independently lost in multiple lineages. Our analyses also indicate that cell shape and cell border shape are co-dependent characters whereas we did not find correlation between a simple life habit classification and any specific nanomorphological character. CONCLUSIONS: These results, compatible with the fact that multiple types of nanostructures can generate hydrophobicity, suggest that the diversity and complexity of snake skin surface nano-morphology are dominated by phylogenetic rather than habitat-specific functional constraints. The present descriptive study opens the perspective of investigating the cellular self-organisational cytoskeletal processes controlling the patterning of different skin surface nanostructures in snakes and lizards.


Assuntos
Biodiversidade , Nanoestruturas/química , Filogenia , Serpentes/classificação , Animais , Ecossistema , Nanoestruturas/ultraestrutura , Processos Estocásticos
11.
Molecules ; 24(7)2019 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-30934764

RESUMO

Orthopaedic surgery comes with an inherent risk of bacterial infection, prolonged antibiotic therapy and revision surgery. Recent research has focused on nanostructured surfaces to improve the bactericidal and osseointegrational properties of implants. However, an understanding of the mechanical properties of bactericidal materials is lacking. In this work, the surface properties of hydrothermal TiO2 nanostructured surfaces are investigated for their effect on bactericidal efficiency and cellular metabolic activity of human osteoblast cells. TiO2 nanostructures, approximately 307 nm in height and 14 GPa stiffness, were the most effective structures against both gram-positive (Staphylococcus aureus) and gram-negative (Pseudomonas aeruginosa) bacteria. Statistical analysis significantly correlated structure height to the death of both bacteria strains. In addition, the surface contact angle and Young's modulus were correlated to osteoblast metabolic activity. Hydrophilic surfaces with a contact angle between 35 and 50° produced the highest cellular metabolic activity rates after 24 hours of incubation. The mechanical tests showed that nanostructures retain their mechanical stability and integrity over a long time-period, reaffirming the surfaces' applicability for implants. This work provides a thorough examination of the surface, mechanical and wettability properties of multifunctional hydrothermally synthesised nanostructured materials, capable of killing bacteria whilst improving osteoblast metabolic rates, leading to improved osseointegration and antibacterial properties of orthopaedic implants.


Assuntos
Fenômenos Fisiológicos Bacterianos , Metabolismo Energético , Nanoestruturas/química , Osteoblastos/metabolismo , Titânio/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Nanoestruturas/ultraestrutura , Análise Espectral , Propriedades de Superfície
12.
Molecules ; 24(7)2019 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-30959919

RESUMO

The present study aims to investigate the impact of thermal energy storage aggregate (TESA) and nano-titanium (NT) on properties of structural concrete. TESA was made of scoria encapsulated with phase change materials (PCMs). Coarse aggregates were replaced by TESA at 100% by volume of aggregate and NT was added at 5% by weight of cement. Compressive strength, probability of corrosion, thermal performance, and microstructure properties were studied. The results indicated that the presence of TESA reduced the compressive strength of concrete, although the strength was still high enough to be used as structural concrete. The use of TESA significantly improved the thermal performance of concrete, and slightly improved the resistance of corrosion in concrete. The thermal test results showed that TESA concrete reduces the peak temperature by 2 °C compared to the control. The addition of NT changed the microstructure of concrete, which resulted in higher compressive strength. Additionally, the use of NT further enhanced the thermal performance of TESA concrete by reducing the probability of corrosion remarkably. These results confirmed the crucial role of NT in improving the permeability and the thermal conductivity of mixtures containing PCM. In other words, the charging and discharging of TESA was enhanced with the presence of NT in the mixture.


Assuntos
Materiais de Construção/análise , Nanoestruturas/química , Condutividade Térmica , Titânio/química , Força Compressiva , Corrosão , Nanoestruturas/ultraestrutura
13.
Mater Sci Eng C Mater Biol Appl ; 100: 598-607, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30948096

RESUMO

In the present study carbon xerogels are used for the first time to study the fibroblast cell growth. For that, carbon xerogel microspheres are synthesized and thereafter functionalized with carbon nanofibers followed by the 1,3-dipolar cycloaddition of azomethine ylides (the so called "Prato reaction") or the addition of aryl diazonium salts (the so called "Tour reaction") to improve its wettability. The presence of nanofibers produces a huge improvement of the functionalization degree (59 versus 372 µmol/g for pristine carbon spheres and carbon spheres with 30% of carbon nanofibers, respectively) in spite of the blockage of the carbon spheres porosity caused after the nanofibers growth. This improvement was explained on the base of the increase of the number of probable active sites for the addition reactions (CC bonds) and the accessibility to these active sites (accessible surface area) by the presence of nanofibers. These high functionalization degrees reflect a promising potential of these materials in biomedical applications. Toxicity results obtained using a fibroblast cell line showed that samples are biocompatible for this kind of cells and that the presence of carbon fibers on the surface of the spheres increases the cells proliferation in a high extend reaching in some case values around 150% regarding the control. This study evidences that carbon aerogels could be interesting materials in biological applications, an unexplored field for this type of materials, being biocompatible, favouring the proliferation of cells and achieving high functionalization degrees.


Assuntos
Carbono/química , Géis/química , Animais , Proliferação de Células , Sobrevivência Celular , Camundongos , Microesferas , Células NIH 3T3 , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Espectroscopia Fotoeletrônica , Porosidade
14.
Nat Commun ; 10(1): 966, 2019 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-30814497

RESUMO

Current chemical-fuel-driven nanomotors are driven by gas (e.g. H2, O2, NH3) which only provides motion ability, and can produce waste (e.g. Mg(OH)2, Pt). Here, inspired by endogenous biochemical reactions in the human body involving conversion of amino acid L-arginine to nitric oxide (NO) by NO synthase (NOS) or reactive oxygen species (ROS), we report on a nanomotor made of hyperbranched polyamide/L-arginine (HLA). The nanomotor utilizes L-arginine as fuel for the production of NO both as driving force and to provide beneficial effects, including promoting endothelialisation and anticancer effects, along with other beneficial by-products. In addition, the HLA nanomotors are fluorescent and can be used to monitor the movement of nanomotors in vivo in the future. This work presents a zero-waste, self-destroyed and self-imaging nanomotor with potential biological application for the treatment of various diseases in different tissues including blood vessels and tumours.


Assuntos
Nanoestruturas/química , Óxido Nítrico/metabolismo , Arginina/metabolismo , Fontes de Energia Bioelétrica , Bioengenharia , Fluorescência , Células Endoteliais da Veia Umbilical Humana , Humanos , Células MCF-7 , Movimento (Física) , Nanoestruturas/ultraestrutura , Nanotecnologia , Nylons/metabolismo , Espécies Reativas de Oxigênio/metabolismo
15.
Int J Nanomedicine ; 14: 1575-1585, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30880966

RESUMO

Background: Polymeric delivery systems have been elucidated over the last few years as an approach of achieving high therapeutic effect to the local site of malignant disease patients who have cancer. Polypyrrole (Ppy) is a potential organic conducting polymer which has long been recognized as a versatile material due to its excellent stability, conductive properties, and great absorbance in the range of near-infrared (NIR). It is tremendously versatile for use in various biomedical fields such as cancer therapy. NIR irradiation-activated treatment platform technologies are now being considered to be novel and exciting options in potential nanomedicine. However, the realistic photothermal use of Ppy-applied nanomaterials is yet in its early phase, and there are a few disadvantages of Ppy, such as its water insolubility. In the clinic, the common approach for treatment of lung cancer is the delivery of therapeutic active substances through intratumoral administration. Nevertheless, the tumor uptake, regional retention, mechanism of treatment, and tissue organ penetration regarding the developed strategy of this nanomaterial with photothermal hyperthermia are important issues for exerting effective cancer therapy. Materials and methods: In this study, we developed a cationic Ppy-polyethylenimine nanocomplex (NC) with photothermal hyperthermia to study its physicochemical characteristics, including size distribution, zeta potential, and transmission electron microscopy, scanning electron microscopy, and Fourier transform infrared morphology. We also examined the cellular uptake effect on lung cancer cells, the photothermal properties, intracellularly generated reactive oxygen species (ROS), and cytotoxicity. Results: The results suggested that this nanocarrier system was able to effectively attach onto lung cancer cells for subsequent endocytosis. The NCs taken up were able to absorb NIR and then converted the NIR light into local hyperthermia with its intracellular photothermal performance to provide local hyperthermic treatment. This regionally generated hyperthermia also induced ROS formation and improved the killing of lung cancer cells as a promising local photothermal therapy. Conclusion: This development of a nanocarrier would bring a novel therapeutic strategy for lung cancer in the future.


Assuntos
Hipertermia Induzida , Neoplasias Pulmonares/terapia , Nanoestruturas/química , Fototerapia , Polietilenoimina/química , Polímeros/química , Pirróis/química , Espécies Reativas de Oxigênio/metabolismo , Comunicação Celular , Linhagem Celular Tumoral , Sobrevivência Celular , Fluorescência , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/ultraestrutura , Nanoestruturas/ultraestrutura , Propriedades de Superfície
16.
Int J Nanomedicine ; 14: 1725-1736, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30880976

RESUMO

Background: Nanophase surface properties of titanium alloys must be obtained for a suitable biological performance, particularly to facilitate cell adhesion and bone tissue formation. Obtaining a bulk nanostructured material using severe plastic deformation is an ideal processing route to improve the mechanical performance of titanium alloys. By decreasing the grain size of a metallic material, a superior strength improvement can be obtained, while surface modification of a nanostructured surface can produce an attractive topography able to induce biological responses in osteoblastic cells. Methods: Aiming to achieve such an excellent synergetic performance, a processing route, which included equal channel angular pressing (ECAP), hot and cold extrusion, and heat treatments, was used to produce a nanometric and ultrafine-grained (UFG) microstructure in the Ti-6Al-7Nb alloy (around of 200 nm). Additionally, UFG samples were surface-modified with acid etching (UFG-A) to produce a uniform micron and submicron porosity on the surface. Subsequently, alkaline treatment (UFG-AA) produced a sponge-like nanotopographic substrate able to modulate cellular interactions. Results: After several kinds of biological tests for both treatment conditions (UFG-A and UFG-AA), the main results have shown that there was no cytotoxicity, expressed alkaline phosphatase activity and total protein amounts without statistical differences compared to control. However, the UFG-AA samples presented an attractive effect on the cell membranes, and cell adhesions were preferentially induced as compared with UFG-A. Both conditions demonstrated cell projections, but for UFG-AA, cells were more widely dispersed, and more quantities of filopodia formation could be observed. Conclusion: Herein, the reasons for such behaviors are discussed, and further results are presented in addition to those mentioned above.


Assuntos
Tecnologia Biomédica/métodos , Tamanho da Partícula , Titânio/farmacologia , Líquidos Corporais/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Teste de Materiais , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Molhabilidade
17.
J Cancer Res Clin Oncol ; 145(5): 1213-1219, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30847551

RESUMO

Recent efforts in the area of photothermal therapy (PTT) follow two important aims: (i) selective targeting of plasmonic nanoparticles to the tumor and (ii) real-time guidance of PTT operation through employing multimodal imaging modalities. In the present study, we utilized a multifunctional theranostic nanoplatform constructed from iron (III) oxide-gold (Fe2O3@Au) core-shell nanoparticles to fulfill these aims. The Au shell exhibits surface plasmon resonance, a property that is exploited to realize PTT. The magnetic core enables Fe2O3@Au to be employed as a magnetic resonance imaging (MRI) contrast agent. Furthermore, the magnetic core has the potential to establish a magnetic drug targeting strategy through which Fe2O3@Au can be directed to the tumor site by means of magnetic field. To test these potentials, Balb/c mice bearing CT26 colorectal tumor model were intravenously injected with Fe2O3@Au. Immediately after injection, a magnet was placed on the tumor site for 3 h to concentrate nanoparticles, followed by the near infrared (NIR) laser irradiation. MRI study confirmed the accumulation of nanoparticles within the tumor due to T2 enhancement capability of Fe2O3@Au. The in vivo thermometry results demonstrated that the tumors in magnetic targeting group had a significantly higher temperature elevation rate upon NIR irradiation than non-targeted group (~ 12 °C vs. 8.5 °C). The in vivo antitumor assessment revealed that systemic injection of Fe2O3@Au in combination with magnetic targeting and NIR irradiation resulted in complete remission of tumor growth. Therefore, Fe2O3@Au can establish a targeted PTT strategy for efficient eradication of tumor cells under the guidance of MRI.


Assuntos
Compostos Férricos , Ouro , Hipertermia Induzida , Imagem por Ressonância Magnética , Nanoestruturas , Fototerapia , Nanomedicina Teranóstica , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Compostos Férricos/química , Ouro/química , Humanos , Hipertermia Induzida/métodos , Raios Infravermelhos , Imagem por Ressonância Magnética/métodos , Camundongos , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Neoplasias/patologia , Neoplasias/terapia , Fototerapia/métodos , Análise Espectral , Nanomedicina Teranóstica/métodos , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Chemosphere ; 224: 237-246, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30822730

RESUMO

Among nanomaterials, zinc oxide (ZnO) is notable for its excellent biocidal properties. In particular, it can be incorporated in mortars to prevent biofouling. However, the morphology of these nanomaterials (NMs) and their impact on the action against biofouling are still unknown. This study aimed to assess how the morphology and surface modification can affect the ecotoxicology of ZnO NMs. The morphologies evaluated were nanoparticles (NPs) and nanorods (NRs), and the ZnO NMs were tested pure and with surface modification through amine functionalization (@AF). The toxic effects of these NMs were evaluated by acute and chronic ecotoxicity tests with the well-established model microcrustacean Daphnia magna. The ZnO NMs were characterized by transmission electron microscopy, X-ray diffraction and infrared spectroscopy. The EC5048h to D. magna indicated higher acute toxicity of ZnO@AF NRs compared to all tested NMs. Regarding the chronic test with D. magna, high toxic effects on reproduction and longevity were observed with ZnO@AF NRs and effects on growth were observed with ZnO NRs. In general, all tested ZnO NMs presented high toxicity when compared to the positive control, and the NRs presented higher toxicity than NPs in all tested parameters, regardless of the form tested (pure or with surface modification). Additionally, the pathways of ecotoxicity of the tested ZnO NMs was found to be related to combined factors of Zn ion release, effective diameter of particles and NM internalization in the organism.


Assuntos
Daphnia/efeitos dos fármacos , Ecotoxicologia/métodos , Nanoestruturas/toxicidade , Óxido de Zinco/toxicidade , Animais , Nanopartículas/toxicidade , Nanopartículas/ultraestrutura , Nanoestruturas/ultraestrutura , Nanotubos/toxicidade , Nanotubos/ultraestrutura , Propriedades de Superfície , Testes de Toxicidade , Óxido de Zinco/química
19.
Eur J Pharm Biopharm ; 139: 59-67, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30836179

RESUMO

Nanostructured coatings of dental implants have shown great potential in overcoming many challenges responsible for implant failure. In this study, nano spray drying technology was utilized to produce novel biocompatible nanocoatings with antibacterial activity. The experiments were applied on titanium discs, which were used as a model material for dental implants. The produced nanocoatings consisted of poly(lactic-co-glycolic acid) as a biodegradable polymer and norfloxacin as a model antibiotic. Scanning electron microscopy results revealed an average particle size ranging between 400 and 600 nm. In vitro release studies showed a biphasic drug release profile with a burst release within the first 48 h, followed by a sustained release phase until the end of the experiment. The antibacterial activity of the nanocoatings was evaluated against Escherichia coli where the norfloxacin loaded nanocoatings achieved up to 99.83% reduction in the number of viable bacterial colonies. Finally, in vitro biocompatibility of the nanocoatings was investigated using mouse fibroblasts (L929) as a standard sensitive cell line for cytotoxicity assessment. Cell proliferation on the surface of the titanium discs was studied using fluorescence microscopy followed by cell counting assay. Both methods confirmed the biocompatibility of the examined nanocoatings. In conclusion, nano spray drying is a promising technique for preparing tailor-made nanocoatings, thereby representing an innovative approach for the surface modification of dental implants.


Assuntos
Antibacterianos/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Implantes Dentários , Nanoestruturas/química , Animais , Antibacterianos/química , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Liberação Controlada de Fármacos , Escherichia coli/efeitos dos fármacos , Fibroblastos , Teste de Materiais/métodos , Camundongos , Microscopia Eletrônica de Varredura , Nanoestruturas/ultraestrutura , Norfloxacino/química , Norfloxacino/farmacologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Propriedades de Superfície , Titânio
20.
Int J Biol Macromol ; 130: 564-572, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30831167

RESUMO

In this study, we report the synthesis of graphene oxide nanosheets (GON) by a modified Hummers method. Then, a protease purified from the Penaeus vannamei shrimp was immobilized on the GON activated with glutaraldehyde. Several techniques such as SEM, DLS and FTIR were applied to characterize the different nano-structures at the different levels. The immobilization of the protease on the GON activated with glutaraldehyde did not affect the optimum pH, but significantly improved thermal stability and stability at extreme pH values, as well as activity at 90 °C. After 24 h of incubation at 90 °C, the free enzyme retained less than 10% of the activity, while the immobilized enzyme kept more than 90% of its original activity. The apparent Km and Vmax for Penaeus vannamei protease remained fairly similar after immobilization, a very relevant data considering the large size of the substrate (casein).In the hydrolysis of casein at 70 °C and in the presence of 2 M urea, the immobilized enzyme exhibited a higher activity than the free enzyme. The results indicate that the immobilization of the enzyme Penaeus vannamei protease on GON activated with glutaraldehyde increases its already high stability against environmental stresses and makes it suitable for biotechnological and industrial applications.


Assuntos
Enzimas Imobilizadas , Glutaral/química , Grafite , Nanoestruturas/química , Óxidos , Penaeidae/enzimologia , Peptídeo Hidrolases/química , Animais , Estabilidade Enzimática , Grafite/química , Concentração de Íons de Hidrogênio , Hidrólise , Cinética , Nanoestruturas/ultraestrutura , Termodinâmica
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