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1.
Small ; 18(15): e2107778, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35257482

RESUMO

Electrochemical (EC) actuators have garnered significant attention in recent years, yet there are still some critical challenges to limit their application range, such as responsive time, multifunctionality, and actuating direction. Herein, an EC actuator with a back-to-back structure is fabricated by stacking two membranes with bilayer V2 O5 nanowires/single-walled carbon nanotubes (V2 O5 NWs/SWCNTs) networks, and shows a synchronous high actuation amplitude (about ±9.7 mm, ±28.4°) and multiple color changes. In this back-to-back structure, the inactive SWCNTs layer is used as a conductive current collector, and the bilayer network is attached to a porous polymer membrane. The dual-responsive processes of V2 O5 nanowires (V2 O5 NWs) actuation films and actuators are also deeply investigated through in situ EC X-ray diffraction and Raman spectroscopy. The results show that the EC actuation of the V2 O5 NWs/SWCNTs film is highly related to the redox behavior of the pseudocapacitive V2 O5 NWs layer. At last, both V2 O5 NWs and W18 O49 nanowires (W18 O49 NWs)-based EC actuators are constructed to demonstrate the multicolor changes and multidirectional actuation induced by the opposite lattice changes of V2 O5 NWs and W18 O49 NWs during ionic de-/intercalation, guiding the design of multifunctional EC actuators in the future.


Assuntos
Nanotubos de Carbono , Nanofios , Íons , Nanotubos de Carbono/química , Nanofios/química , Polímeros/química , Porosidade
2.
Nanomedicine ; 45: 102590, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35905841

RESUMO

The positive single-stranded nature of COVID-19 mRNA led to the low proof-reading efficacy for its genome authentication. Thus mutant covid-19 strains have been rapidly evolving. Besides Alpha, Beta, Gamma, Delta, and Omicron variants, currently, subvariants of omicron are circulating, including BA.4, BA.5, and BA.2.12.1. Therefore, the speedy development of a rapid, simple, and easier diagnosis method to deal with new mutant covid viral infection is critically important. Many diagnosis methods have been developed for COVID-19 detection such as RT-PCR and antibodies detection. However, the former is time-consuming, laborious, and expensive, and the latter relies on the production of antibodies making it not suitable for the early diagnosis of viral infection. Many lateral-flow methods are available but might not be suitable for detecting the mutants, Here we proved the concept for the speedy development of a simple, rapid, and cost-effective early at-home diagnosis method for mutant Covid-19 infection by combining a new aptamer. The idea is to use the current lateral flow Covid-19 diagnosis system available in the market or to use one existing antibody for the Lateral Flow Nitrocellulose filter. To prove the concept, the DNA aptamer specific to spike proteins (S-proteins) was conjugated to gold nanoparticles and served as a detection probe. An antibody that is specific to spike proteins overexpressed on COVID viral particles was used as a second probe immobilized to the nitrocellulose membrane. The aptamer conjugated nanoparticles were incubated with spike proteins for half an hour and tested for their ability to bind to antibodies anchored on the nitrocellulose membrane. The gold nanoparticles were visualized on the nitrocellulose membrane due to interaction between the antigen (S-protein) with both the aptamer and the antibody. Thus, the detection of viral antigen can be obtained within 2 h, with a cost of less than $5 for the diagnosis reagent. In the future, as long as the mutant of the newly emerged viral surface protein is reported, a peptide or protein corresponding to the mutation can be produced by peptide synthesis or gene cloning within several days. An RNA or DNA aptamer can be generated quickly via SELEX. A gold-labeled aptamer specific to spike proteins (S-proteins) will serve as a detection probe. Any available lateral-flow diagnosis kits with an immobilized antibody that has been available on the market, or simply an antibody that binds COVID-19 virus might be used as a second probe immobilized on the nitrocellulose. The diagnosis method can be carried out by patients at home if a clinical trial verifies the feasibility and specificity of this method.


Assuntos
Aptâmeros de Nucleotídeos , COVID-19 , Nanopartículas Metálicas , Anticorpos , Antígenos Virais , COVID-19/diagnóstico , Teste para COVID-19 , Colódio , Ouro , Humanos , RNA , RNA Mensageiro , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética
3.
BMC Plant Biol ; 21(1): 54, 2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33478390

RESUMO

BACKGROUND: Forest trees have important economic and ecological value. As a model tree, poplar has played a significant role in elucidating the molecular mechanisms underlying tree biology. However, a lack of mutant libraries and time-consuming stable genetic transformation processes severely limit progress into the functional characterization of poplar genes. A convenient and fast transient transformation method is therefore needed to enhance progress on functional genomics in poplar. METHODS: A total of 11 poplar clones were screened for amenability to syringe infiltration. Syringe infiltration was performed on the lower side of the leaves of young soil-grown plants. Transient expression was evaluated by visualizing the reporters ß-glucuronidase (GUS) and green fluorescent protein (GFP). The experimental parameters of the syringe agroinfiltration were optimized based on the expression levels of the reporter luciferase (LUC). Stably transformed plants were regenerated from transiently transformed leaf explants through callus-induced organogenesis. The functions of Populus genes in secondary cell wall-thickening were characterized by visualizing lignin deposition therein after staining with basic fuchsin. RESULTS: We greatly improved the transient transformation efficiency of syringe Agrobacterium infiltration in poplar through screening for a suitable poplar clone from a variety of clones and optimizing the syringe infiltration procedure. The selected poplar clone, Populus davidiana × P. bolleana, is amenable to Agrobacterium syringe infiltration, as indicated by the easy diffusion of the bacterial suspension inside the leaf tissues. Using this technique, we localized a variety of poplar proteins in specific intracellular organelles and illustrated the protein-protein and protein-DNA interactions. The transiently transformed leaves could be used to generate stably transformed plants with high efficiency through callus induction and differentiation processes. Furthermore, transdifferentiation of the protoxylem-like vessel element and ectopic secondary wall thickening were induced in the agroinfiltrated leaves via the transient overexpression of genes associated with secondary wall formation. CONCLUSIONS: The application of P. davidiana × P. bolleana in Agrobacterium syringe infiltration provides a foundation for the rapid and high-throughput functional characterization of Populus genes in intact poplar plants, including those involved in wood formation, and provides an effective alternative to Populus stable genetic transformation.


Assuntos
Agrobacterium/fisiologia , Populus/genética , Transformação Genética , Agrobacterium/genética , Parede Celular/genética , Parede Celular/fisiologia , Genes Reporter , Lignina/metabolismo , Folhas de Planta/genética , Folhas de Planta/fisiologia , Plantas Geneticamente Modificadas , Populus/fisiologia , Seringas
4.
BMC Plant Biol ; 19(1): 97, 2019 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-30866808

RESUMO

BACKGROUND: Regulation of lignin biosynthesis is known to occur at the level of transcription factors (TFs), of which R2R3-MYB family members have been proposed to play a central role via the AC cis-elements. Despite the important roles of TFs in lignin biosynthesis, the post-translational regulation of these TFs, particularly their ubiquitination regulation, has not been thoroughly explored. RESULTS: We describe the discovery of a Populus tomentosa E2 ubiquitin-conjugating enzyme 34 (PtoUBC34), which is involved in the post-translational regulation of transactivation activity of lignin-associated transcriptional repressors PtoMYB221 and PtoMYB156. PtoUBC34 is localized at the endoplasmic reticulum (ER) membrane where it interacts with transcriptional repressors PtoMYB221 and PtoMYB156. This specific interaction allows for the translocation of TFs PtoMYB221 and PtoMYB156 to the ER and reduces their repression activity in a PtoUBC34 abundance-dependent manner. By taking a molecular biology approach with quantitative real-time polymerase chain reaction (qRT-PCR) analysis, we found that PtoUBC34 is expressed in all aboveground tissues of trees in P. tomentosa, and in particular, it is ubiquitous in all distinct differentiation stages across wood formation, including phloem differentiation, cambium maintaining, early and developing xylem differentiation, secondary cell wall thickening, and programmed cell death. Additionally, we discovered that PtoUBC34 is induced by treatment with sodium chloride and heat shock. CONCLUSIONS: Our data suggest a possible mechanism by which lignin biosynthesis is regulated by ER-localized PtoUBC34 in poplar, probably through the ER-associated degradation (ERAD) of lignin-associated repressors PtoMYB221 and PtoMYB156.


Assuntos
Degradação Associada com o Retículo Endoplasmático , Lignina/biossíntese , Populus/genética , Fatores de Transcrição/metabolismo , Enzimas de Conjugação de Ubiquitina/metabolismo , Parede Celular/metabolismo , Retículo Endoplasmático/metabolismo , Regulação da Expressão Gênica de Plantas , Floema/genética , Floema/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Populus/metabolismo , Fatores de Transcrição/genética , Enzimas de Conjugação de Ubiquitina/genética , Madeira/genética , Madeira/metabolismo , Xilema/genética , Xilema/metabolismo
5.
Analyst ; 140(2): 551-9, 2015 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-25412211

RESUMO

A novel electrochemical immunosensor assay (EIA) for highly sensitive and specific detection of Escherichia coli O157:H7 has been developed. This immunosensor is constructed by the assembly of capture antibody on SG-PEDOT-AuNPs composites modified glass carbon electrode. In the presence of target E. coli O157:H7, horseradish peroxidase (HRP)-labeled antibody is captured on the electrode surface to form a sandwich-type system via the specific identification. As a result, E. coli O157:H7 detection is realized by outputting a redox current from electro-reduction of hydrogen peroxide reaction catalyzed by HRP. In our assay, the combination of the unique properties of sulfonated graphene (SG) and gold nanoparticles (AuNPs) can not only accelerate electron transfer on electrode interface, but also provide an excellent scaffold for the conjugation of capture antibody that significantly improves the target capture efficiency and enhances the sensitivity of the biosensor. The results reveal the calibration plot obtained for E. coli O157:H7 is approximately linear from 7.8 × 10-7.8 × 10(6) colony-forming unit (cfu) mL(-1) with the limit of detection of 3.4 × 10 cfu mL(-1). In addition, the biosensor has been successfully applied to the quantitative assay of E. coli O157:H7 in synthetic samples (spring water and milk). Hence, the developed electrochemical-based immunosensor might provide a useful and practical tool for E. coli O157:H7 determination and related food safety analysis and clinical diagnosis.


Assuntos
Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Infecções por Escherichia coli/prevenção & controle , Escherichia coli O157/imunologia , Microbiologia de Alimentos , Animais , Anticorpos Antibacterianos/imunologia , Anticorpos Imobilizados , Compostos Bicíclicos Heterocíclicos com Pontes/química , Contaminação de Alimentos/análise , Doenças Transmitidas por Alimentos/microbiologia , Doenças Transmitidas por Alimentos/prevenção & controle , Ouro/química , Grafite/química , Peroxidase do Rábano Silvestre/química , Peróxido de Hidrogênio/química , Imunoensaio/métodos , Nanopartículas Metálicas/química , Leite/microbiologia , Polímeros/química , Pontos Quânticos/química , Coloração e Rotulagem , Água/análise , Microbiologia da Água
6.
ACS Nano ; 16(8): 12635-12644, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35930746

RESUMO

Electronic textiles, inherited with the wearability of conventional clothes, are deemed fundamental for emerging wearable electronics, particularly in the Internet of Things era. However, the electronic waste produced by electronic textiles will further exacerbate the severe pollution in traditional textiles. Here, we develop a large-scale green electronic textile using renewable bio-based polylactic acid and sustainable eutectic gallium-indium alloys. The green electronic textile is extremely abrasion resistant and can degrade naturally in the environment even if abrasion produces infinitesimal amounts of microplastics. The mass loss and performance change rates of the reconstituted green electronic textiles are all below 5.4% after going through the full-cycle recycling procedure. This green electronic textile delivers high physiological comfort (including electronic comfort and thermal-moisture comfort), enables wireless power supply (without constraints by, e.g., wires and ports), has 2 orders of magnitude better air and moisture permeability than the body requires, and can lower skin temperature by 5.2 °C.


Assuntos
Plásticos , Têxteis , Eletrônica
7.
J Nanosci Nanotechnol ; 11(12): 10760-4, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22408990

RESUMO

Targeted delivery carriers are receiving considerable attention, the development of a more precise targeted delivery carrier is critical for the advancement of cancer chemotherapy. In this study, we evaluated the effects of RGD-conjugated poly (lactic acid-co-lysine)-(Arginine-Glycine-Aspartic) nanoparticles (PLA-PLL-RGD NPs) on targeted delivery to Bacp-37 breast cancer bearing mice. PLA-PLL-RGD NPs were prepared by using the emulsion-solvent evaporation method. A subsequent MTT assay indicated that the NPs were non-toxic and had good biocompatibility. In vitro, the results of Confocal Laser Scanning Microscope (CLSM) and FAC Scan flow cytometry (FACS) indicated that the PLA-PLL-RGD NPs can bind more significantly to human umbilical vein endothelial cells, compared to PLA-PLL NPs. In vivo, the results of target imaging and biodistribution showed that PLA-PLL-RGD can significantly target to tumor of Bacp-37 breast cancer bearing mice. These results demonstrated that PLA-PLL-RGD NPs can effectively enhance targeted efficiency in vivo, and have the potential to be used as targeted delivery carrier.


Assuntos
Neoplasias da Mama/patologia , Ácido Láctico/química , Lisina/química , Nanopartículas , Oligopeptídeos/química , Polímeros/química , Ensaios Antitumorais Modelo de Xenoenxerto , Materiais Biocompatíveis , Feminino , Citometria de Fluxo , Humanos , Microscopia Confocal , Oligopeptídeos/farmacocinética , Poliésteres , Distribuição Tecidual
8.
Adv Mater ; 33(45): e2104681, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34558123

RESUMO

Fiber electronics with mechanosensory functionality are highly desirable in healthcare, human-machine interfaces, and robotics. Most efforts are committed to optimize the electronically readable interface of fiber mechanoreceptor, while the user interface based on naked-eye readable output is rarely explored. Here, a scalable fiber electronics that can simultaneously visualize and digitize the mechanical stimulus without external power supply, named self-powered optoelectronic synergistic fiber sensors (SOEFSs), are reported. By coupling of space and surface charge polarization, a new mechanoluminescent (ML)-triboelectric synergistic effect is realized. It contributes to remarkable enhancement of both electrical (by 100%) and optical output (by 30%), as well as novel temporal-spatial resolution mode for motion capturing. Based on entirely new thermoplastic ML material system and spinning process, industrial-level continuously manufacture and recycling processes of SOEFS are realized. Furthermore, SOEFSs' application in human-machine interface, virtual reality, and underwater sensing, rescue, and information interaction is demonstrated.


Assuntos
Eletrônica/métodos , Fibras Ópticas , Fontes de Energia Elétrica , Eletrodos , Eletrônica/instrumentação , Desenho de Equipamento , Polímeros de Fluorcarboneto/química , Medições Luminescentes , Nanofibras/química , Polivinil/química , Dispositivos Eletrônicos Vestíveis
9.
J Mech Behav Biomed Mater ; 121: 104593, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34090118

RESUMO

To overcome the interfacial problem between X-ray radiopaque ZrO2 fillers and polymer resin in dental composites, monodispersed SiO2@ZrO2@SiO2 (SZS) microspheres with narrow size distribution were prepared by a controlled sol-gel method. In the presence of SiO2 coating layer over SiO2@ZrO2 (SZ) microspheres, they were easily silanized same as SiO2 microspheres. Ethoxylated bisphenol A dimethacrylate (EBPADMA) with a higher molecular weight and a lower viscosity was used as base resin monomer mixed with a low amount of diluent triethylene glycol dimethacrylate (TEGDMA). Additionally, the addition of a small amount of pore agent acetone dicarboxylic acid (ADCA) produced some voids, thereby effectively reducing the polymerization shrinkage of the resin. The prepared dental composites combining 52 wt% monodispersed silica microsphere, 20 wt% SZS microspheres, exhibited significantly enhanced capacity in radiopacity (higher than tooth enamel) and very low shrinkage (<0.1%). It also has better mechanical properties than resin composites filled with SiO2 microspheres, and its strength can meet practical applications. The properties of the radiopaque dental composite were to be further tuned by varying the amount of SZS microspheres contents, and the radiopaque resin has an advantage over the commercial one in that it is clinically nondestructive.


Assuntos
Metacrilatos , Dióxido de Silício , Bis-Fenol A-Glicidil Metacrilato , Resinas Compostas , Teste de Materiais , Polietilenoglicóis , Polimerização , Ácidos Polimetacrílicos , Viscosidade
10.
J Control Release ; 330: 173-184, 2021 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-33316298

RESUMO

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death worldwide. Analogous to the border customs, liver mainly functions as a filter to detoxify chemicals and metabolite administered orally or intravenously. Besides, the liver cancer cells overexpress the drug exporters which cause high drug effluxion from liver cancer cells, leading to chemoresistance and a diminished chemotherapeutic effect on liver cancer. Recently, we found that RNA nanoparticles display rubber-like property that can rapidly deliver therapeutics to tumor site efficiently and the rest of the RNA nanoparticle were cleared by renal excretion within half hour after systemic injection. Therefore, we designed a new multivalent RNA nanoparticle harboring three copies of hepatocyte targeting-ligands, one copy of miR122, and 24 copies of Paclitaxel to overcome the drug effluxion and chemoresistance thus, synergistically treating HCC. The hepatocyte targeting ligands introduce tumor specificity to the RNA nanoparticles as they selectively bind and internalize into liver cancer cells. The rubber-like RNA nanoparticles allow for enhanced targeting ability to the HCC tumors. The RNA nanoparticles carrying miR122 and PTX were delivered to the liver cancer cells efficiently due to their rubber-like property to enhance their EPR as well as the receptor-mediated endocytosis by hepatocyte targeting-ligands. The miR122 efficiently silenced the drug exporters and the oncogenic proteins. The synergistic effect between miR122 and PTX was confirmed by HSA (Highest Single Agent) synergy model. IC50 was determined to be 460 nM. In vivo studies on mice xenografts revealed that the RNA nanoparticle predominantly accumulated in HCC tumor sites and efficiently inhibited the tumor growth after multiple IV injection. This demonstrates the potential of the rubber-like multivalent RNA nanoparticles to conquest the liver cancer, a currently incurable lethal disease.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , Nanopartículas , Preparações Farmacêuticas , Animais , Carcinoma Hepatocelular/tratamento farmacológico , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Resistencia a Medicamentos Antineoplásicos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Camundongos , MicroRNAs/genética , MicroRNAs/uso terapêutico , Paclitaxel/uso terapêutico , Borracha/uso terapêutico
11.
Biomed Microdevices ; 12(1): 169-77, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19924539

RESUMO

We report a novel and facile method for fabricating coaxial microfluidic devices processing various dimensions at low cost, in which polypropylene hollow fibers or glass capillaries are used as the tip of the dispersed phase injection tube. With this coaxial microfluidic device,monodisperse biocompatible microspheres ranging from 300 to 800 µm were obtained by collecting oil-in-water or water-in-oil emulsions and solidifying the suspended microspheres. Microsphere size could be controlled by changing the tips or tuning the concentrations of the dispersed and continuous phases. By adding functional nanoparticles into the dispersed phase, it was demonstrated that fluorescent and magnetic microspheres can be fabricated easily using these microfluidic devices.


Assuntos
Materiais Biocompatíveis/síntese química , Técnicas Analíticas Microfluídicas/instrumentação , Microesferas , Polímeros/síntese química , Ação Capilar , Desenho de Equipamento , Análise de Falha de Equipamento , Teste de Materiais , Miniaturização , Tamanho da Partícula
12.
ACS Appl Mater Interfaces ; 12(46): 51225-51235, 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33164509

RESUMO

In vitro drug release systems have recently received tremendous attention because they allow noninvasive, convenient, and prolonged administration of pharmacological agents. On-demand epidermal drug release systems can improve treatment efficiency, prevent multidrug resistance, and minimize drug toxicity to healthy cells. In addition, real-time monitoring of drug content is also essential for guiding the determination of drug dosage and replacing drug carriers in time. Therefore, it is important to integrate the above properties in one ideal epidermal patch. Herein, photonic crystals (PCs) based on Fe3O4@C nanoparticles were introduced into drug-loaded poly(N-isopropylacrylamide-co-acrylic acid) (P(NIPAM-AAc)) hydrogel-functionalized textiles. Drug loading and release depended on the expansion and contraction of the hydrogels. The lower critical solution temperature (LCST) of the hydrogels was adjusted to 40 °C, which is higher than the skin temperature, by varying the content of hydrophilic comonomer acrylic acid (AAc) to store the drug at room temperature, and on-demand release was achieved by mild thermal stimulation. Moreover, the lattice spacing (d) of PCs varied with the expansion and contraction of the hydrogels, which can cause the color of P(NIPAM-AAc) hydrogel-functionalized textiles to change. These synchronous thermoresponsive chromic drug uptake and release behaviors provided an effective method for visual and real-time monitoring of drug content. Furthermore, in view of the poor mechanical properties of hydrogel wound dressings, textile matrices were composited to prevent holistic breaking during the stretching process. Biological experiments proved that the drug-loaded P(NIPAM-AAc) hydrogel-functionalized textiles had good antibacterial properties and wound-healing effects.


Assuntos
Portadores de Fármacos/química , Hidrogéis/química , Têxteis , Acrilamidas/química , Animais , Antibacterianos/química , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Bandagens , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Óxido Ferroso-Férrico/química , Interações Hidrofóbicas e Hidrofílicas , Camundongos , Moxifloxacina/química , Moxifloxacina/metabolismo , Moxifloxacina/farmacologia , Nanopartículas/química , Polímeros/química , Staphylococcus aureus/efeitos dos fármacos , Temperatura , beta-Ciclodextrinas/química
13.
ACS Nano ; 14(10): 13180-13191, 2020 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-32902260

RESUMO

Rubber is a fascinating material in both industry and daily life. The development of elastomeric material in nanotechnology is imperative due to its economic and technological potential. By virtue of their distinctive physicochemical properties, nucleic acids have been extensively explored in material science. The Phi29 DNA packaging motor contains a 3WJ with three angles of 97°, 125°, and 138°. Here, the rubber-like property of RNA architectures was investigated using optical tweezers and in vivo imaging technologies. The 3WJ 97° interior angle was contracted or stretched to 60°, 90°, and 108° at will to build elegant RNA triangles, squares, pentagons, cubes, tetrahedrons, dendrimers, and prisms. RNA nanoarchitecture was stretchable and shrinkable by optical tweezer with multiple extension and relaxation repeats like a rubber. Comparing to gold and iron nanoparticles with the same size, RNA nanoparticles display stronger cancer-targeting outcomes, while less accumulation in healthy organs. Generally, the upper limit of renal excretion is 5.5 nm; however, the 5, 10, and 20 nm RNA nanoparticles passed the renal filtration and resumed their original structure identified in urine. These findings solve two previous mysteries: (1) Why RNA nanoparticles have an unusually high tumor targeting efficiency since their rubber or amoeba-like deformation property enables them to squeeze out of the leaky vasculature to improve the EPR effect; and (2) why RNA nanoparticles remain non-toxic since they can be rapidly cleared from the body via renal excretion into urine with little accumulation in the body. Considering its controllable shape and size plus its rubber-like property, RNA holds great promises for industrial and biomedical applications especially in cancer therapeutics delivery.


Assuntos
Nanopartículas , Neoplasias , Humanos , Neoplasias/diagnóstico por imagem , RNA , Eliminação Renal , Borracha
14.
ACS Appl Mater Interfaces ; 11(47): 44673-44681, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31690067

RESUMO

Extreme heat events are mainly responsible for weather-related human mortality due to climate change. However, there is a lack of outdoor thermal management for protecting people from extreme heat events. We present a novel infrared-radiation-enhanced nanofiber membrane (NFM) that has good infrared resonance absorption and selectively radiates thermal radiation of the human body through the atmosphere and into the cold outer space. The NFM comprises polyamide 6 (PA6) nanofibers and randomly distributed SiO2 submicron spheres and has sufficient air permeability and thermal-moisture comfortability because of its interconnect nanopores and micropores. We measure the sky radiative cooling performance under a clear sky, and PA6/SiO2 NFM produces temperatures that are about 0.4-1.7 °C lower than those of commercial textiles when covering dry and wet hands and temperatures 1.0-2.5 °C lower than the ambient temperature when thermal conduction and convection are isolated in a closed device. Our processed PA6/SiO2 NFM combines sky radiative cooling with thermal management of the human body very well, which will promote the development of radiative cooling textiles.


Assuntos
Nanofibras/química , Temperatura Cutânea/efeitos da radiação , Têxteis/efeitos da radiação , Caprolactama/análogos & derivados , Caprolactama/química , Corpo Humano , Humanos , Raios Infravermelhos , Nanofibras/efeitos da radiação , Polímeros/química , Dióxido de Silício/química , Têxteis/análise
15.
Science ; 365(6449): 150-155, 2019 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-31296765

RESUMO

Although guest-filled carbon nanotube yarns provide record performance as torsional and tensile artificial muscles, they are expensive, and only part of the muscle effectively contributes to actuation. We describe a muscle type that provides higher performance, in which the guest that drives actuation is a sheath on a twisted or coiled core that can be an inexpensive yarn. This change from guest-filled to sheath-run artificial muscles increases the maximum work capacity by factors of 1.70 to 2.15 for tensile muscles driven electrothermally or by vapor absorption. A sheath-run electrochemical muscle generates 1.98 watts per gram of average contractile power-40 times that for human muscle and 9.0 times that of the highest power alternative electrochemical muscle. Theory predicts the observed performance advantages of sheath-run muscles.


Assuntos
Órgãos Artificiais , Fibra de Carbono , Contração Muscular , Fibras Musculares Esqueléticas , Nanotubos de Carbono , Resistência à Tração
16.
ACS Appl Mater Interfaces ; 10(34): 28331-28339, 2018 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-29989788

RESUMO

Cancer diagnostics has been an important research field, and identification of small lesions that are less noticeable plays a vital role in thoroughly removing the tumor, thereby reducing the recurrence rate of cancer. Herein, we synthesized a signal self-amplifiable photoacoustic (PA) liposomal nanoprobe composed by ammonium hydrogen carbonate (AHC) payload and aggregated purpurin-18 (P18) within the bilayer. Under PA laser irradiation, P18 aggregates efficiently generated local heat, leading to the launch of wide-band ultrasonic emission. In parallel, the heat also triggered the decomposition of AHC and production of CO2 bubbles, which consequently dramatically amplified the acoustic signal. For clinical translation, by decorating bladder cancer (BC) specific CD44v6 antibody onto nanoprobe, we were capable of utilizing this high sensitive and specific PA probe for human BC tissue imaging. The results indicated that small tumor lesion (<5 mm) was identified and the tumor-to-normal tissue ratio was ∼18 folds enhancement by using this PA probe, which rendered the tumor boundary distinct. All together, we developed a new strategy for exploring high-performance imaging probes, which might potentially benefit for the imaging-guided surgery in clinics.


Assuntos
Neoplasias da Bexiga Urinária , Humanos , Lipossomos , Técnicas Fotoacústicas , Análise Espectral
17.
J Control Release ; 285: 46-55, 2018 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-30008370

RESUMO

Single instillation (SI) reduces recurrence of non-muscle-invasive bladder cancer by chemoresecting floating tumor cells and residual tumor lesions (RTLs) after transurethral resection of the bladder, but with limited efficacy. Current studies improved this by prolonging retention time and increasing penetration to bladder wall, ignoring that the two separate factors should be treated in different ways. Here, we introduced a smart gel system-based SI to prevent re-implantation of tumor cells (RTCs) and ablate RTLs in a "divide-and-rule" approach. The gel system was synthesized by PEG-PAMAM and dextran aldehyde and composed of gold nanorods and gemcitabine for photothermal therapy and chemotherapy, respectively. It was developed to provide dextran aldehyde-selective adhesion with tissue amines. Since tumor surface expressed high levels of collagen, the exposed amines could act as adhesion points for the gel system. Thus, the gel presented more affinity to tumor tissues. When being instilled, it could form a protective layer on the inner face of the entire bladder wall immediately, preventing RTCs in early time. And it persisted long at the tumor site, ablating RTLs. Our data proved the gel system improved intravesical treatment efficacy in a "divide-and-rule" approach and might be a promising treatment strategy for SI.


Assuntos
Antineoplásicos/administração & dosagem , Dendrímeros/química , Desoxicitidina/análogos & derivados , Doxorrubicina/administração & dosagem , Géis/química , Polietilenoglicóis/química , Neoplasias da Bexiga Urinária/tratamento farmacológico , Administração Intravesical , Animais , Antineoplásicos/uso terapêutico , Desoxicitidina/administração & dosagem , Desoxicitidina/uso terapêutico , Dextranos/química , Doxorrubicina/uso terapêutico , Sistemas de Liberação de Medicamentos/métodos , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Gencitabina
18.
Nanoscale ; 10(37): 17663-17670, 2018 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-30206611

RESUMO

Zinc oxide (ZnO) often serves as protein microarray substrates owing to its outstanding fluorescence enhancement effect. However, the integration of functional substrates with microfluidic technology to detect cancer biomarkers still needs to be optimized and promoted, for example, the optimization of micro/nanostructure and hydrophilic modification strategies for fluorescence immunoassays. Here, ZnO nanorod arrays were constructed on the inner wall of glass capillaries through a microfluidic chemical method, and the electrostatic layer by layer self-assembly was applied to modify the nanorod array with hydrophilic polyelectrolyte-polyacrylic acid (PAA). The effects of the flow rate and the reagent concentration on the morphology of the ZnO nanorod array were investigated. The ZnO nanorod array-based glass capillary, prepared at 25 µL min-1 for 4 min with 50 mM Zn2+ in solution, showed a remarkable enhancement in fluorescence performance. In addition, the introduction of PAA suppressed the interference of nonspecific protein and improved the antibody loading capacity effectively. In the detection of carcinoembryonic antigen, the limit of detection reached 100 fg mL-1, which indicated that the ZnO@PAA nanorod array-based microfluidic device exhibits remarkable fluorescence detection performance towards protein markers and possesses potential to be applied to point-of-care diagnostics and high throughput cancer biomarker detection.


Assuntos
Resinas Acrílicas/química , Imunofluorescência , Dispositivos Lab-On-A-Chip , Nanotubos , Óxido de Zinco/química , Antígeno Carcinoembrionário/análise , Nanoestruturas
19.
ACS Appl Mater Interfaces ; 8(7): 4676-83, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26809194

RESUMO

The rapid development of wearable electronics in recent years has brought increasing energy consumption, making it an urgent need to focus on personal energy harvesting, storage and management. Herein, a textile-based personal energy management device with multilayer-coating structure was fabricated by encapsulating commercial nylon cloth coated with silver nanowires into polydimethylsiloxane using continuous and facile dip-coating method. This multilayer-coating structure can not only harvest mechanical energy from human body motion to power wearable electronics but also save energy by keeping people warm without losing heat to surroundings and wasting energy to heat empty space and inanimate objects. Fluoroalkylsilanes (FAS) were grafted onto the surface of the film through one single dip-coating process to improve its energy harvesting performance, which has hardly adverse effect to heat insulation and Joule heating property. In the presence of FAS modification, the prepared film harvested mechanical energy to reach a maximum output power density of 2.8 W/m(2), charged commercial capacitors and lighted LEDs, showing its potential in powering wearable electronics. Furthermore, the film provided 8% more thermal insulation than normal cloth at 37 °C and efficiently heated to 40 °C within 4 min when applied the voltage of only 1.5 V due to Joule heating effect. The high flexibility and stability of the film ensures its wide and promising application in the wearable field.


Assuntos
Fontes de Energia Elétrica , Nanofios/química , Silanos/química , Têxteis , Eletrônica , Humanos , Nylons/química , Silanos/síntese química , Prata/química
20.
Oncotarget ; 7(3): 2855-66, 2016 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-26625203

RESUMO

Calcium phosphate nanoparticles are safe and effective delivery vehicles for small interfering RNA (siRNA), as a result of their excellent biocompatibility. In this work, mPEG-PE (polyethylene glycol-L-α-phosphatidylethanolamine) was synthesized and used to prepare nanoparticles composed of mPEG-PE and calcium phosphate for siRNA delivery. Calcium phosphate and mPEG-PE formed the stable hybrid nanoparticles through self-assembly resulting from electrostatic interaction in water. The average size of the hybrid nanoparticles was approximately 53.2 nm with a negative charge of approximately -16.7 mV, which was confirmed by dynamic light scattering (DLS) measurements. The nanoparticles exhibited excellent stability in serum and could protect siRNA from ribonuclease (RNase) degradation. The cellular internalization of siRNA-loaded nanoparticles was evaluated in SMMC-7721 cells using a laser scanning confocal microscope (CLSM) and flow cytometry. The hybrid nanoparticles could efficiently deliver siRNA to cells compared with free siRNA. Moreover, the in vivo distribution of Cy5-siRNA-loaded hybrid nanoparticles was observed after being injected into tumor-bearing nude mice. The nanoparticles concentrated in the tumor regions through an enhanced permeability and retention (EPR) effect based on the fluorescence intensities of tissue distribution. A safety evaluation of the nanoparticles was performed both in vitro and in vivo demonstrating that the hybrid nanoparticle delivery system had almost no toxicity. These results indicated that the mPEG-PE/CaP hybrid nanoparticles could be a stable, safe and promising siRNA nanocarrier for anticancer therapy.


Assuntos
Materiais Biocompatíveis/efeitos adversos , Fosfatos de Cálcio/efeitos adversos , Portadores de Fármacos/efeitos adversos , Nanopartículas/efeitos adversos , Polietilenoglicóis/efeitos adversos , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/uso terapêutico , Animais , Materiais Biocompatíveis/administração & dosagem , Transporte Biológico , Fosfatos de Cálcio/administração & dosagem , Linhagem Celular Tumoral , Portadores de Fármacos/administração & dosagem , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/administração & dosagem , Polietilenoglicóis/administração & dosagem , Interferência de RNA
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