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1.
An Acad Bras Cienc ; 91(3): e20180237, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31365648

RESUMO

The aim of this study was to develop polyurethane (PU) wound dressing incorporated with cobalt nitrate using electrospinning technique. The morphology analysis revealed that the developed composites exhibited reduced fiber and pore diameter than the pristine PU. The electrospun membranes exhibited average porosity in the range of 67% - 71%. Energy-dispersive X-ray spectra (EDS) showed the presence of cobalt in the PU matrix. The interaction of cobalt nitrate with PU matrix was evident in Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). The contact angle results indicated the improved wettability of the prepared PU/cobalt nitrate composites (82° ± 2) than the pure PU (100° ± 1). The incorporation of cobalt nitrate into the PU matrix enhanced the surface roughness and mechanical strength as evident in the atomic force microscopy (AFM) and tensile test analysis. The blood compatibility assays revealed the anticoagulant nature of the prepared composites by displaying prolonged blood clotting time than the PU control. Further, the developed composite exhibited less toxicity nature as revealed in the hemolysis and cytotoxicity studies. It was observed that the PU wound dressing added with cobalt nitrate fibers exhibited enhanced physicochemical, better blood compatibility parameters and enhanced fibroblast proliferation rates which may serve as a potential candidate for wound dressings.


Assuntos
Materiais Biocompatíveis/administração & dosagem , Cobalto/administração & dosagem , Teste de Materiais , Engenharia Tecidual , Cicatrização , Materiais Biocompatíveis/química , Cobalto/química , Humanos , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier
2.
J Photochem Photobiol B ; 197: 111541, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31272033

RESUMO

Here, we report the novel fabrication of ZnO nanoparticles using the Costus igneus leaf extract. Gas chromatography-mass spectrometry (GC-MS) and proton nuclear magnetic resonance (1H NMR) spectroscopy to determine the bioactive components present in the plant extract. The synthesis of Ci-ZnO NPs (C. igneus- coated zinc oxide nanoparticles) was accomplished using a cost-effective and simple technique. Ci-ZnO NPs were specified using UV-visible spectroscopy, FTIR, XRD, and TEM. Ci-ZnO NPs was authenticated by UV-Vis and exhibited a peak at 365 nm. The XRD spectra proved the crystalline character of the Ci-ZnO NPs synthesized as hexagonal wurtzite. The FTIR spectrum illustrated the presence of possible functional groups present in Ci-ZnO NPs. The TEM micrograph showed evidence of the presence of a hexagonal organization with a size of 26.55 nm typical of Ci-ZnO NPs. The α-amylase and α-glucosidase inhibition assays demonstrated antidiabetic activity of Ci-ZnO NPs (74 % and 82 %, respectively), and the DPPH [2,2-diphenyl-1-picrylhydrazyl hydrate] assay demonstrated the antioxidant activity of the nanoparticles (75%) at a concentration of 100 µg/ml. The Ci-ZnO NPs exhibited promising antibacterial and biofilm inhibition activity against the pathogenic bacteria Streptococcus mutans, Lysinibacillus fusiformis, Proteus vulgaris, and Vibrio parahaemolyticus. Additionally, the Ci-ZnO NPs showed biocompatibility with mammalian RBCs with minimum hemolytic activity (0.633 % ±â€¯0.005 %) at a concentration of 200 µg/ml.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/química , Biofilmes/efeitos dos fármacos , Nanopartículas Metálicas/química , Extratos Vegetais/química , Óxido de Zinco/química , Antibacterianos/síntese química , Antibacterianos/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Costus/química , Costus/metabolismo , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/fisiologia , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/fisiologia , Química Verde , Hemólise/efeitos dos fármacos , Humanos , Insulina/química , Nanopartículas Metálicas/toxicidade , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Extratos Vegetais/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo
3.
J Nanobiotechnology ; 17(1): 82, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31291960

RESUMO

Skin damages are defined as one of most common lesions people suffer from, some of wounds are notoriously difficult to eradicate such as chronic wounds and deep burns. Existing wound therapies have been proved to be inadequate and far from satisfactory. The cutting-edge nanotechnology offers an unprecedented opportunity to revolutionize and invent new therapies or boost the effectiveness of current medical treatments. In particular, the nano-drug delivery systems anchor bioactive molecules to applied area, sustain the drug release and explicitly enhance the therapeutic efficacies of drugs, thus making a fine figure in field relevant to skin regeneration. This review summarized and discussed the current nano-drug delivery systems holding pivotal potential for wound healing and skin regeneration, with a special emphasis on liposomes, polymeric nanoparticles, inorganic nanoparticles, lipid nanoparticles, nanofibrous structures and nanohydrogel.


Assuntos
Materiais Biocompatíveis/química , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/química , Fenômenos Fisiológicos da Pele , Cicatrização/efeitos dos fármacos , Animais , Liberação Controlada de Fármacos , Humanos , Hidrogéis/química , Lipídeos/química , Lipossomos/química , Polímeros/química , Regeneração
4.
J Photochem Photobiol B ; 197: 111545, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31326847

RESUMO

Proper waste utilization in order to promote value added product is a promising scientific practice in recent era. Inspiring from the recurring trend, we propose a single step oxidative pyrolysis derived fluorescent carbon dots (C-dots) from Allium sativum peel, which is a natural, nontoxic, and waste raw material. Because of its excellent optical properties, and photostability this C-dots have been used in versatile area of applications. Due to its immediate water dispersing character, C-dots reinforced Poly(acrylic acid) (PAA) films revealed improvement in uniaxial stretching behavior and can be used as transparent sunlight conversion film. The nanocomposite film has been tested against rigorous simulated sunlight which proved almost identical sunlight conversion behavior with no photo-bleachable character which is definitely added an extra quality of transparent polymer films. Moreover, the C-dots dispersion has been used as in vitro biomarker for living cells owing to its ease in solubility, biocompatibility, non-cytotoxicity and bright fluorescence even in subcutaneous environment. For this case, adipose derived mesenchymal stem cells (ADMSCs) have been chosen and injected to rabbit ear skin to perform two-photon imaging experiment. The present work opens a new avenue towards the large-scale synthesis of bio-waste based fluorescent C-dots, paving the way for their versatile applications.


Assuntos
Allium/química , Nitrogênio/química , Fotodegradação/efeitos da radiação , Pontos Quânticos/química , Enxofre/química , Luz Solar , Resinas Acrílicas/química , Tecido Adiposo/citologia , Allium/metabolismo , Animais , Materiais Biocompatíveis/química , Carbono/química , Sobrevivência Celular/efeitos dos fármacos , Frutas/química , Frutas/metabolismo , Química Verde , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Microscopia de Fluorescência , Pontos Quânticos/toxicidade , Coelhos , Pele/efeitos dos fármacos , Pele/patologia , Solubilidade
5.
J Photochem Photobiol B ; 196: 111508, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31152936

RESUMO

Cardiovascular malady (CVM) isn't just the essential driver of death in created western nations, yet additionally, its sickness load is expanding in China. Oxidative pressure initiated free radicals assume a basic job in cell forms involved in atherosclerosis and numerous other heart illnesses. Quercetin (QC) is cancer prevention agents medicate which is demonstrated that successfully secures against CVMs. Encapsulations of medications in polymeric materials are generally utilized in creating continued and controllable medication discharge, or to keep away from the debasement of non-discharged medications. In this present work, a novel arrangement of polymeric superparamagnetic nano-silica (SiN)@poly(lactic-co-glycolic acid) (PLGA) (SiN@PLGA) stacked with QC was created by means of lyophilization method so as to improve poor watery solvency and steadiness of the medication with the point of preventing atherosclerosis. The aftereffects of SEM investigation and the checking, TEM affirmed the manufacture of the circular nanocomposite, smooth surface, and thin size dispersion. The discharge profile of QC from the particles was explored by deciding the medication sum discharged at explicit interims for by iridescence. The data got from this investigation encourages the structure and manufacture of nanocomposite as conceivable conveyance frameworks for epitome, assurance and controlled arrival of the flavonoid QC which is expecting to secure against CVMs.


Assuntos
Nanocompostos/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Quercetina/química , Dióxido de Silício/química , Animais , Aterosclerose/patologia , Aterosclerose/prevenção & controle , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Liberação Controlada de Fármacos , Camundongos , Miocárdio/metabolismo , Miocárdio/patologia , Nanocompostos/toxicidade , Quercetina/metabolismo , Quercetina/uso terapêutico
6.
Chem Soc Rev ; 48(13): 3513-3536, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31157810

RESUMO

Bioconjugates are multifunctional constructs in which biomolecules like peptides, proteins, vitamins and nucleic acids are endowed with the properties of specific payloads. These constructs recently emerged as a new generation of high-precision therapeutics, with several representatives reaching the market. This success stimulated an intense search for new biocompatible synthetic methodologies to connect both components and to control the bioconjugate's function. Despite the remarkable advances made in this field, most of the technologies developed for the construction of bioconjugates were engineered to yield stable constructs that can endure complex physiological conditions. Because of this, the use of reversible covalent bonds in the synthesis of bioconjugates has been rather overlooked, notwithstanding the potential of this strategy to generate stimuli responsive constructs that may operate in areas like the selective delivery of drugs, live-cell imaging and new theranostic approaches. Boronic acids are a well-known class of reagents that have been widely used in modern synthesis for the formation of C-C and C-heteroatom bonds. Apart from this, boronic acids exhibit an exquisite reversible coordination profile that can be explored as a molecular construction tool featuring specific mechanisms to control the structure and biological properties of bioconjugates. In this review, the use of boronic acids in the construction of therapeutically useful bioconjugates will be discussed, focusing on the molecular mechanisms that allow the use of these reagents as bioconjugation warheads, as central pieces of linker structures and as functional payloads.


Assuntos
Materiais Biocompatíveis/química , Ácidos Borônicos/química , Animais , Materiais Biocompatíveis/uso terapêutico , Ácidos Borônicos/uso terapêutico , Sistemas de Liberação de Medicamentos , Desenho de Drogas , Humanos , Nanomedicina Teranóstica
7.
Chem Soc Rev ; 48(14): 3740-3770, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31206104

RESUMO

Among the wide range of materials used for remediating environmental contaminants, modified and functionalised nanoclays show particular promise as advanced sorbents, improved dispersants, or biodegradation enhancers. However, many chemically modified nanoclay materials are incompatible with living organisms when they are used in natural systems with detrimental implications for ecosystem recovery. Here we critically review the pros and cons of functionalised nanoclays and provide new perspectives on the synthesis of environmentally friendly varieties. Particular focus is given to finding alternatives to conventional surfactants used in modified nanoclay products, and to exploring strategies in synthesising nanoclay-supported metal and metal oxide nanoparticles. A large number of promising nanoclay-based sorbents are yet to satisfy environmental biocompatibility in situ but opportunities are there to tailor them to produce "biocompatible" or regenerative/reusable materials.


Assuntos
Materiais Biocompatíveis/química , Recuperação e Remediação Ambiental , Nanocompostos/química , Humanos , Tamanho da Partícula , Propriedades de Superfície
8.
An Acad Bras Cienc ; 91(2): e20190018, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31241710

RESUMO

Tissue engineering holds as a prominent technique to repair or replace the damaged human parts to recreate its native function. In this research, a novel scaffold based on polyurethane (PU) comprising megni oil was electrospun for tissue engineering applications. The obtained polyurethane blended with megni oil nanofibers were characterized by scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), contact angle measurement and atomic force microscopy (AFM). Furthermore, the blood compatibility of the fabricated nanocomposites evaluated through activated prothrombin time (APTT), partial thromboplastin time (PT) and hemolysis assay to determine the anticoagulant nature. The morphological results showed that the fabricated nanocomposites showed reduced fiber size (789 ± 143.106 nm) than the pristine control (890 ± 116.91 nm). The interaction between PU and megni oil was identified by the hydrogen bond formation evident in the FTIR. The incorporation of megni oil in the PU decreased the wettability behavior (113.3° ± 1.528) and improved the surface roughness (646 nm). Preliminary evaluation of blood compatibility assessments was carried out using APTT, PT and hemolysis assay revealed the enhanced antithrombogenicity nature of the fabricated nanocomposites than the PU. Hence, we conclude that the fabricated new nanocomposite membrane with desirable characteristics which might find potential application in the tissue engineering applications.


Assuntos
Materiais Biocompatíveis/química , Nanocompostos/química , Óleos/química , Poliuretanos/química , Engenharia Tecidual/métodos , Teste de Materiais , Espectroscopia de Infravermelho com Transformada de Fourier
9.
Int J Nanomedicine ; 14: 3471-3490, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31190805

RESUMO

Background: Zinc-doped hydroxyapatite has been proposed as a graft biomaterial for bone regeneration. However, the effect of zinc on osteoconductivity is still controversial, since the release and resorption of calcium, phosphorus, and zinc in graft-implanted defects have rarely been studied. Methods: Microspheres containing alginate and either non-doped carbonated hydroxyapatite (cHA) or nanocrystalline 3.2 wt% zinc-doped cHA (Zn-cHA) were implanted in critical-sized calvarial defects in Wistar rats for 1, 3, and 6 months. Histological and histomorphometric analyses were performed to evaluate the volume density of newly formed bone, residual biomaterial, and connective tissue formation. Biomaterial degradation was characterized by transmission electron microscopy (TEM) and synchrotron radiation-based X-ray microfluorescence (SR-µXRF), which enabled the elemental mapping of calcium, phosphorus, and zinc on the microsphere-implanted defects at 6 months post-implantation. Results: The bone repair was limited to regions close to the preexistent bone, whereas connective tissue occupied the major part of the defect. Moreover, no significant difference in the amount of new bone formed was found between the two microsphere groups. TEM analysis revealed the degradation of the outer microsphere surface with detachment of the nanoparticle aggregates. According to SR-µXRF, both types of microspheres released high amounts of calcium, phosphorus, and zinc, distributed throughout the defective region. The cHA microsphere surface strongly adsorbed the zinc from organic constituents of the biological fluid, and phosphorus was resorbed more quickly than calcium. In the Zn-cHA group, zinc and calcium had similar release profiles, indicating a stoichiometric dissolution of these elements and non-preferential zinc resorption. Conclusions: The nanometric size of cHA and Zn-cHA was a decisive factor in accelerating the in vivo availability of calcium and zinc. The high calcium and zinc accumulation in the defect, which was not cleared by the biological medium, played a critical role in inhibiting osteoconduction and thus impairing bone repair.


Assuntos
Alginatos/química , Regeneração Óssea , Cálcio/metabolismo , Durapatita/química , Microesferas , Nanopartículas/química , Zinco/química , Zinco/metabolismo , Animais , Materiais Biocompatíveis/química , Disponibilidade Biológica , Regeneração Óssea/efeitos dos fármacos , Carbonatos/química , Morte Celular , Linhagem Celular , Sobrevivência Celular , Feminino , Camundongos , Nanopartículas/ultraestrutura , Ratos Wistar , Crânio/fisiologia , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
10.
Int J Nanomedicine ; 14: 3615-3627, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31190815

RESUMO

Purpose: Modified top-down procedure was successfully employed in the synthesis of aragonite nanoparticles (NPs) from cheaply available natural seawater cockle shells. This was with the aim of developing a pH-sensitive nano-carrier for effective delivery of doxorubicin (DOX) on MCF-7 breast cancer cell line. Methods: The shells were cleaned with banana pelts, ground using a mortar and pestle, and stirred vigorously on a rotary pulverizing blending machine in dodecyl dimethyl betane solution. This simple procedure avoids the use of stringent temperatures and unsafe chemicals associated with NP production. The synthesized NPs were loaded with DOX to form DOX-NPs. The free and DOX-loaded NPs were characterized for physicochemical properties using field emission scanning electron microscopy, transmission electron microscopy, zeta potential analysis, Fourier transform infrared spectroscopy, and X-ray diffraction. The release profile, cytotoxicity, and cell uptake were evaluated. Results: NPs had an average diameter of 35.50 nm, 19.3% loading content, 97% encapsulation efficiency, and a surface potential and intensity of 19.1±3.9 mV and 100%, respectively. A slow and sustained pH-specific controlled discharge profile of DOX from DOX-NPs was observed, clearly showing apoptosis/necrosis induced by DOX-NPs through endocytosis. The DOX-NPs had IC50 values 1.829, 0.902, and 1.0377 µg/mL at 24, 48, and 72 hrs, while those of DOX alone were 0.475, 0.2483, and 0.0723 µg/mL, respectively. However, even at higher concentration, no apparent toxicity was observed with the NPs, revealing their compatibility with MCF-7 cells with a viability of 92%. Conclusions: The modified method of NPs synthesis suggests the tremendous potential of the NPs as pH-sensitive nano-carriers in cancer management because of their pH targeting ability toward cancerous cells.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Doxorrubicina/administração & dosagem , Doxorrubicina/uso terapêutico , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Materiais Biocompatíveis/química , Neoplasias da Mama/patologia , Carbonato de Cálcio/química , Doxorrubicina/farmacologia , Liberação Controlada de Fármacos , Feminino , Humanos , Concentração de Íons de Hidrogênio , Células MCF-7 , Musa/química , Nanopartículas/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Difração de Raios X
11.
Chemistry ; 25(47): 10995-11006, 2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31206798

RESUMO

Low-dimensional nanomaterials (LDNs) are receiving increasing attention in cancer therapy owing to their unique properties, especially the large surface area-to-volume ratio. LDNs such as metallic nanoparticles (NPs), hydroxyapatite NPs, graphene derivatives, and black phosphorus (BP) nanosheets have been proposed for drug delivery, photothermal/photodynamic therapies, and multimodal theranostic treatments. The therapeutic effectiveness is mainly based on the physical characteristics of LDNs, but their inherent bioactivity has not been fully capitalized. In this Minireview, recent advances in the anti-cancer effects of various types of LDNs with inherent chemotherapeutic bioactivity are described and the bioactivity mechanisms are discussed on the cellular and molecular levels. BP, one of the newest and exciting members of the LDN family, is highlighted owing to the excellent inherent bioactivity, selectivity, and biocompatibility in cancer therapy. LDNs and related derivatives possess inherent bioactivity and selective chemotherapeutic effects suggesting large potential as nanostructured anti-cancer agents in cancer therapy.


Assuntos
Nanoestruturas/química , Neoplasias/tratamento farmacológico , Nanomedicina Teranóstica , Materiais Biocompatíveis/química , Materiais Biocompatíveis/uso terapêutico , Fosfatos de Cálcio/química , Fosfatos de Cálcio/uso terapêutico , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Nanoestruturas/uso terapêutico , Fósforo/química , Fósforo/uso terapêutico
12.
Nat Commun ; 10(1): 2705, 2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-31221969

RESUMO

Folded single chain polymeric nano-objects are the molecular level soft material with ultra-small size. Here, we report an easy and scalable method for preparing single-chain nanogels (SCNGs) with improved efficiency. We further investigate the impact of the dynamic molecular conformational change of SCNGs on cellular interactions from molecular to bulk scale. First, the supramolecular unfoldable SCNGs efficiently deliver siRNAs into stem cells as a molecular drug carrier in a conformation-dependent manner. Furthermore, the conformation changes of SCNGs enable dynamic and precise manipulation of ligand tether structure on 2D biomaterial interfaces to regulate the ligand-receptor ligation and mechanosensing of cells. Lastly, the dynamic SCNGs as the building blocks provide effective energy dissipation to bulk biomaterials such as hydrogels, thereby protecting the encapsulated stem cells from deleterious mechanical shocks in 3D matrix. Such a bottom-up molecular tailoring strategy will inspire further applications of single-chain nano-objects in the biomedical area.


Assuntos
Engenharia Celular/métodos , Portadores de Fármacos/química , Hidrogéis/química , Nanopartículas/química , Polímeros/química , Materiais Biocompatíveis/química , Diferenciação Celular/genética , Linhagem Celular , Humanos , Células-Tronco Mesenquimais/fisiologia , Conformação Molecular , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/metabolismo
13.
Nat Commun ; 10(1): 2566, 2019 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-31189915

RESUMO

There is clinical and scientific interest in developing local anesthetics with prolonged durations of effect from single injections. The need for such is highlighted by the current opioid epidemic. Site 1 sodium channel blockers such as tetrodotoxin (TTX) are extremely potent, and can provide very long nerve blocks but the duration is limited by the associated systemic toxicity. Here we report a system where slow release of TTX conjugated to a biocompatible and biodegradable polymer, poly(triol dicarboxylic acid)-co-poly(ethylene glycol) (TDP), is achieved by hydrolysis of ester linkages. Nerve block by the released TTX is enhanced by administration in a carrier with chemical permeation enhancer (CPE) properties. TTX release can be adjusted by tuning the hydrophilicity of the TDP polymer backbone. In vivo, 1.0-80.0 µg of TTX released from these polymers produced a range of durations of nerve block, from several hours to 3 days, with minimal systemic or local toxicity.


Assuntos
Anestésicos Locais/administração & dosagem , Portadores de Fármacos/química , Bloqueio Nervoso/métodos , Bloqueadores dos Canais de Sódio/administração & dosagem , Tetrodotoxina/administração & dosagem , Anestesia Local/métodos , Anestésicos Locais/farmacocinética , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/toxicidade , Plásticos Biodegradáveis/química , Plásticos Biodegradáveis/toxicidade , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Preparações de Ação Retardada/administração & dosagem , Portadores de Fármacos/toxicidade , Composição de Medicamentos/métodos , Avaliação Pré-Clínica de Medicamentos , Liberação Controlada de Fármacos , Masculino , Camundongos , Permeabilidade , Ratos , Ratos Sprague-Dawley , Nervo Isquiático/efeitos dos fármacos , Bloqueadores dos Canais de Sódio/farmacocinética , Tetrodotoxina/farmacocinética , Fatores de Tempo , Resultado do Tratamento
14.
Bioelectrochemistry ; 129: 106-115, 2019 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-31153125

RESUMO

Due to their desirable elastic modulus and density that are similar to natural bone, non-toxic element containing magnesium alloys are regarded as promising bio-degradable materials. A biodegradable HA-particle-reinforced magnesium-matrix composite Mg-3Zn-0.2Ca-1HA (wt%) was fabricated for biomedical application by a combination of high shear solidification (HSS) and hot extrusion technology. The microstructure, mechanical properties, corrosion resistance and cell biocompatibility of the composite were subsequently investigated. In comparison with the matrix alloy, the as-cast Mg-3Zn-0.2Ca-1HA composite obtained by HSS technology exhibited a uniform and fine grained structure, further refined after a hot extrusion ratio of 36:1. The yield strength (0.2%YS), ultimate tensile strength and elongation of the extruded composite were 322 MPa, 341 MPa and 7.6%, respectively. The corrosion rate of the as-extruded Mg-3Zn-0.2Ca-1HA composite was measured to be 1.52 mm/y. Electrochemical and immersion tests showed that the corrosion resistance of the composite is slightly improved comparing to that of the matrix alloy.


Assuntos
Ligas/química , Materiais Biocompatíveis/química , Durapatita/química , Magnésio/química , Zinco/química , Animais , Linhagem Celular , Corrosão , Fibroblastos/citologia , Teste de Materiais , Camundongos , Resistência à Tração
15.
Bioelectrochemistry ; 129: 144-153, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31158799

RESUMO

A microbial fuel cell (MFC) is a potential bio-electrochemical technology that utilizes microorganisms to convert chemical energy into electrical energy. The low power output of MFCs remain the bottleneck for their practical applications. In this paper, a novel, biocompatible and bioelectrocatalytic composite chitosan-nitrogen doped carbon nanotubes-polyaniline (CS-NCNT-PANI) was prepared in situ on the 3D porous NCNT/sponge and applied to an MFC anode. The PANI was grafted on the CS-NCNT backbone to synthesize the ternary composite. This bioanode not only increased the active surface area and capacity but also facilitated bacterial adhesion and enrichment of microbes. Compared with the NCNT/sponge electrode, the charge transfer impedance of the ternary composite bioanode decreased from 14.07â€¯Ω to 2.25 Ω, and the maximum power density increased from 1.4 W·m-3 to 4.2 W·m-3; meanwhile, during the chronoamperometric experiment with a charge-discharge time of 60-60 min, the cumulative charge of the composite bioanode was 18,865.8 C·m-2, which is much higher than that of the NCNT/S anode (3625.3 C·m-2). High-throughput sequencing technology revealed that the ternary composite bioanode had good biocompatibility and high diversity. Therefore, this synthesized ternary composite is a promising candidate as a capacitive and biocompatible anode material in MFC.


Assuntos
Compostos de Anilina/química , Fontes de Energia Bioelétrica , Quitosana/química , Nanotubos de Carbono/química , Bactérias/genética , Bactérias/isolamento & purificação , Materiais Biocompatíveis/química , Fontes de Energia Bioelétrica/microbiologia , Biomassa , Eletricidade , Eletrodos/microbiologia , Nanotubos de Carbono/ultraestrutura , Filogenia , Porosidade
16.
Chem Soc Rev ; 48(15): 4317-4335, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31225558

RESUMO

Biocompatible ionic liquids (Bio-ILs) are an eco- and bio-friendly family of ionic liquids (ILs) useful in applications ranging from the electrochemical to the biomedical fields. The most promising strategies for their synthesis involve using molecules from bio-renewable sources as a basis for both the anionic and cationic counterparts of the Bio-ILs structure. Several studies have been conducted on Bio-IL properties, including their impact on the environment and health safety. Herein, we review progress and strategies towards the synthesis of Bio-ILs and address their ecotoxicological and biological impact. Furthermore, we discuss the impact of using these compounds in a diverse range of applications, with some insights toward their use in the development of improved technologies.


Assuntos
Materiais Biocompatíveis/farmacologia , Tecnologia Biomédica , Líquidos Iônicos/farmacologia , Animais , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Humanos , Líquidos Iônicos/síntese química , Líquidos Iônicos/química
17.
Chem Soc Rev ; 48(10): 2698-2737, 2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-31080987

RESUMO

Calcium phosphates (CaPs) are ubiquitous in nature and vertebrate bones and teeth, and have high biocompatibility and promising applications in various biomedical fields. Nanostructured calcium phosphates (NCaPs) are recognized as promising nanocarriers for drug/gene/protein delivery owing to their high specific surface area, pH-responsive degradability, high drug/gene/protein loading capacity and sustained release performance. In order to control the structure and surface properties of NCaPs, various biomolecules with high biocompatibility such as nucleic acids, proteins, peptides, liposomes and phosphorus-containing biomolecules are used in the synthesis of NCaPs. Moreover, biomolecules play important roles in the synthesis processes, resulting in the formation of various NCaPs with different sizes and morphologies. At room temperature, biomolecules can play the following roles: (1) acting as a biocompatible organic phase to form biomolecule/CaP hybrid nanostructured materials; (2) serving as a biotemplate for the biomimetic mineralization of NCaPs; (3) acting as a biocompatible modifier to coat the surface of NCaPs, preventing their aggregation and increasing their colloidal stability. Under heating conditions, biomolecules can (1) control the crystallization process of NCaPs by forming biomolecule/CaP nanocomposites before heating; (2) prevent the rapid and disordered growth of NCaPs by chelating with Ca2+ ions to form precursors; (3) provide the phosphorus source for the controlled synthesis of NCaPs by using phosphorus-containing biomolecules. This review focuses on the important roles of biomolecules in the synthesis of NCaPs, which are expected to guide the design and controlled synthesis of NCaPs. Moreover, we will also summarize the biomedical applications of NCaPs in nanomedicine and tissue engineering, and discuss their current research trends and future prospects.


Assuntos
Fosfatos de Cálcio/química , Nanocompostos/química , Materiais Biocompatíveis/química , DNA de Cadeia Simples/química , Portadores de Fármacos/química , Química Verde , Humanos , Nanomedicina , Albumina Sérica/química , Engenharia Tecidual
18.
Nat Commun ; 10(1): 2307, 2019 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-31127114

RESUMO

The development of hemostatic technologies that suit a diverse range of emergency scenarios is a critical initiative, and there is an increasing interest in the development of absorbable dressings that can be left in the injury site and degrade to reduce the duration of interventional procedures. In the current study, ß-cyclodextrin polyester (CDPE) hydrogels serve as sacrificial macroporous carriers, capable of degradation under physiological conditions. The CDPE template enables the assembly of imprinted chitosan honeycomb-like monolithic mats, containing highly entangled nanofibers with diameters of 9.2 ± 3.7 nm, thereby achieving an increase in the surface area of chitosan to improve hemostatic efficiency. In vivo, chitosan-loaded cyclodextrin (CDPE-Cs) hydrogels yield significantly lower amounts of blood loss and shorter times to hemostasis compared with commercially available absorbable hemostatic dressings, and are highly biocompatible. The designed hydrogels demonstrate promising hemostatic efficiency, as a physiologically-benign approach to mitigating blood loss in tissue-injury scenarios.


Assuntos
Bandagens , Hemorragia/terapia , Hemostáticos/química , Hidrogéis/química , Animais , Materiais Biocompatíveis/química , Quitosana/química , Ciclodextrinas/química , Modelos Animais de Doenças , Feminino , Hemorragia/etiologia , Técnicas Hemostáticas , Humanos , Masculino , Nanofibras/química , Coelhos , Ratos , Ratos Sprague-Dawley , Sus scrofa , Resultado do Tratamento
19.
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
20.
Nat Commun ; 10(1): 2062, 2019 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-31048680

RESUMO

The prediction of implant behavior in vivo by the use of easy-to-perform in vitro methods is of great interest in biomaterials research. Simulated body fluids (SBFs) have been proposed and widely used to evaluate the bone-bonding ability of implant materials. In view of its limitations, we report here a rapid in vitro method based on calcium titration for the evaluation of in vivo bioactivity. Using four different titanium surfaces, this method identifies that alkaline treatment is the key process to confer bioactivity to titanium whereas no significant effect from heat treatment is observed. The presence of bioactive titanium surfaces in the solution during calcium titration induces an earlier nucleation of crystalline calcium phosphates and changes the crystallization pathway. The conclusions from this method are also supported by the standard SBF test (ISO 23317), in vitro cell culture tests using osteoblasts and in vivo animal experiments employing a pelvic sheep model.


Assuntos
Materiais Biocompatíveis/química , Teste de Materiais/métodos , Próteses e Implantes , Titânio/química , Animais , Interface Osso-Implante , Cálcio/química , Células Cultivadas , Feminino , Modelos Animais , Osseointegração , Osteoblastos , Implantação de Prótese , Ovinos , Propriedades de Superfície , Fatores de Tempo , Titulometria/métodos
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