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1.
Nat Commun ; 11(1): 4530, 2020 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-32913195

RESUMO

Various cancer cells have been demonstrated to have the capacity to form plasmonic gold nanoparticles when chloroauric acid is introduced to their cellular microenvironment. But their biomedical applications are limited, particularly considering the millimolar concentrations and longer incubation period of ionic gold. Here, we describe a simplistic method of intracellular biomineralization to produce plasmonic gold nanoparticles at micromolar concentrations within 30 min of application utilizing polyethylene glycol as delivery vector for ionic gold. We have characterized this process for intracellular gold nanoparticle formation, which progressively accumulates proteins as the ionic gold clusters migrate to the nucleus. This nano-vectorized application of ionic gold emphasizes its potential biomedical opportunities while reducing the quantity of ionic gold and required incubation time. To demonstrate its biomedical potential, we further induce in-situ biosynthesis of gold nanoparticles within MCF7 tumor mouse xenografts which is followed by its photothermal remediation.


Assuntos
Cloretos/administração & dosagem , Portadores de Fármacos/química , Compostos de Ouro/administração & dosagem , Ouro/química , Nanopartículas Metálicas/química , Neoplasias/tratamento farmacológico , Nanomedicina Teranóstica/métodos , Animais , Biomineralização/efeitos da radiação , Feminino , Ouro/efeitos da radiação , Humanos , Hipertermia Induzida/métodos , Íons , Células MCF-7 , Nanopartículas Metálicas/efeitos da radiação , Camundongos , Fotoquimioterapia/métodos , Polietilenoglicóis/química , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Proc Natl Acad Sci U S A ; 117(27): 15473-15481, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32571948

RESUMO

The development of sustainable methods for the degradation of pollutants in water is an ongoing critical challenge. Anthropogenic organic micropollutants such as pharmaceuticals, present in our water supplies in trace quantities, are currently not remediated by conventional treatment processes. Here, we report an initial demonstration of the oxidative degradation of organic micropollutants using specially designed nanoparticles and visible-wavelength sunlight. Gold "Janus" nanorods (Au JNRs), partially coated with silica to enhance their colloidal stability in aqueous solutions while also maintaining a partially uncoated Au surface to facilitate photocatalysis, were synthesized. Au JNRs were dispersed in an aqueous solution containing peroxydisulfate (PDS), where oxidative degradation of both simulant and actual organic micropollutants was observed. Photothermal heating, light-induced hot electron-driven charge transfer, and direct electron shuttling under dark conditions all contribute to the observed oxidation chemistry. This work not only provides an ideal platform for studying plasmonic photochemistry in aqueous medium but also opens the door for nanoengineered, solar-based methods to remediate recalcitrant micropollutants in water supplies.


Assuntos
Nanopartículas Metálicas/efeitos da radiação , Fotólise/efeitos da radiação , Luz Solar , Poluentes Químicos da Água/química , Poluição Química da Água/prevenção & controle , Ouro/química , Ouro/efeitos da radiação , Nanopartículas Metálicas/química , Nanotecnologia/métodos , Nanotubos/química , Nanotubos/efeitos da radiação , Compostos Orgânicos/química , Compostos Orgânicos/toxicidade , Oxirredução/efeitos da radiação , Dióxido de Silício/química , Dióxido de Silício/efeitos da radiação , Água/química , Poluentes Químicos da Água/toxicidade
3.
J Chem Phys ; 152(12): 124712, 2020 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-32241129

RESUMO

Laser illuminated gold nanoparticles (AuNPs) efficiently absorb light and heat up the surrounding medium, leading to versatile applications ranging from plasmonic catalysis to cancer photothermal therapy. Therefore, an in-depth understanding of the thermal, optical, and electron induced reaction pathways is required. Here, the electrophilic DNA nucleobase analog 5-Bromouracil (BrU) has been used as a model compound to study its decomposition in the vicinity of AuNPs illuminated with intense ns laser pulses under various conditions. The plasmonic response of the AuNPs and the concentration of BrU and resulting photoproducts have been tracked by ultraviolet and visible (UV-Vis) spectroscopy as a function of the irradiation time. A kinetic model has been developed to determine the reaction rates of two parallel fragmentation pathways of BrU, and their dependency on laser fluence and adsorption on the AuNP have been evaluated. In addition, the size and the electric field enhancement of the decomposed AuNPs have been determined by atomic force microscopy and finite domain time difference calculations, respectively. A minor influence of the direct photoreaction and a strong effect of the heating of the AuNPs have been revealed. However, due to the size reduction of the irradiated AuNPs, a trade-off between laser fluence and plasmonic response of the AuNPs has been observed. Hence, the decomposition of the AuNPs might be limiting the achievable temperatures under irradiation with several laser pulses. These findings need to be considered for an efficient design of catalytic plasmonic systems.


Assuntos
Bromouracila/química , Nanopartículas Metálicas/química , Ouro/química , Ouro/efeitos da radiação , Cinética , Lasers , Luz , Nanopartículas Metálicas/efeitos da radiação
4.
J Chem Phys ; 151(14): 144712, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31615232

RESUMO

Electrogenerated chemiluminescence (ECL) is a promising technique for low concentration molecular detection. To improve the detection limit, plasmonic nanoparticles have been proposed as signal boosting antennas to amplify ECL. Previous ensemble studies have hinted that spectral overlap between the nanoparticle antenna and the ECL emitter may play a role in signal enhancement. Ensemble spectroscopy, however, cannot resolve heterogeneities arising from colloidal nanoparticle size and shape distributions, leading to an incomplete picture of the impact of spectral overlap. Here, we isolate the effect of nanoparticle-emitter spectral overlap for a model ECL system, coreaction of tris(2,2'-bipyridyl)dichlororuthenium(ii) hexahydrate and tripropylamine, at the single-particle level while minimizing other factors influencing ECL intensities. We found a 10-fold enhancement of ECL among 952 gold nanoparticles. This signal enhancement is attributed exclusively to spectral overlap between the nanoparticle and the emitter. Our study provides new mechanistic insight into plasmonic enhancement of ECL, creating opportunities for low concentration ECL sensing.


Assuntos
Nanopartículas Metálicas/química , Compostos Organometálicos/química , Propilaminas/química , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Eletrodos , Ouro/química , Ouro/efeitos da radiação , Luz , Luminescência , Medições Luminescentes/métodos , Nanopartículas Metálicas/efeitos da radiação , Compostos Organometálicos/efeitos da radiação
5.
Anal Chim Acta ; 1090: 64-71, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31655647

RESUMO

Using carcinoembryonic antigen (CEA) imprinted polymerized ionic liquid hydrogel as a recognition element and hollow gold nanoballs/MoSe2 nanosheets as a photoactive element, a photoelectrochemical (PEC) sensing platform was successfully fabricated. To accomplish the imprinted process under room temperature to maintain the biological activity and the configuration of CEA, and thus to improve the sensing performances, 3-{[{4-N,N-Bis[(carbamoyl)ethylmethacrylate]butyl}((carbamoyl)amino)ethyl methacrylate] -propyl}-1-ethenyl-1H-imidazol-3-ium bromide (BCCPEimBr) ionic liquid was synthesized. By using BCCPEimBr ionic liquid as the functional monomer, CEA as the template, a molecularly imprinted hydrogel film was prepared on a hollow gold nanoballs/MoSe2 nanosheets modified glassy carbon electrode surface. After removing the template, a CEA imprinted photoelectrochemical sensor was successfully fabricated. The imprinted PEC sensor shows good selectivity, sensitivity and stability towards CEA, produces a linear response in the concentration range from 0.05 to 5.0 ng mL-1 and shows a detection limit of 11.2 pg mL-1 (S/N = 3) under the optimized conditions. The imprinted PEC sensor was used to determine CEA in clinical human serum samples accurately. The procedure for the imprinted PEC sensing platform can be used for other biomolecules just by substituting the template.


Assuntos
Antígeno Carcinoembrionário/sangue , Hidrogéis/química , Líquidos Iônicos/química , Nanopartículas Metálicas/química , Nanocompostos/química , Polímeros/química , Técnicas Biossensoriais/métodos , Dissulfetos/química , Técnicas Eletroquímicas/métodos , Ouro/química , Ouro/efeitos da radiação , Humanos , Limite de Detecção , Nanopartículas Metálicas/efeitos da radiação , Impressão Molecular , Molibdênio/química , Fotoquímica/métodos , Reprodutibilidade dos Testes
6.
Analyst ; 144(21): 6193-6196, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31577279

RESUMO

We here describe a photocurrent generation system exploiting gold nanoparticles (AuNPs) that cover perylenediimide-DNA complexes on electrode surfaces. Enhanced photocurrents were generated by the irradiation of the AuNPs, attributed to the efficient excitation of the perylenediimides by a local electric field on the surface of the AuNPs.


Assuntos
DNA/química , Técnicas Eletroquímicas/métodos , Nanopartículas Metálicas/química , Fotoquímica/métodos , Técnicas Eletroquímicas/instrumentação , Eletrodos , Ouro/química , Ouro/efeitos da radiação , Imidas/química , Imidas/efeitos da radiação , Luz , Nanopartículas Metálicas/efeitos da radiação , Perileno/análogos & derivados , Perileno/química , Perileno/efeitos da radiação
7.
Analyst ; 144(19): 5717-5723, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31482883

RESUMO

An innovative visible light-driven photoelectrochemical (PEC) immunosensing system was reasonably established for the sensitive detection of prostate-specific antigen (PSA) by using perovskite metal oxide@gold nanoparticle heterostructures (BaTiO3/Au) as the photoactive materials. When plasmonic Au nanoparticles were directly decorated on BaTiO3, a several times surface plasmon resonance (SPR) enhancement of photocurrent density was induced via the injection of hot electrons from visible light-excited Au nanoparticles into the conduction band of BaTiO3, and the combination of BaTiO3 and Au nanoparticles was employed as a promising platform for developing a photoelectrochemical bioanalysis. As a proof of concept, PSA had been detected by the BaTiO3/Au nanocomposite-based PEC sensor. To design such an immunoassay protocol, a monoclonal anti-PSA capture antibody (cAb)-coated microplate and glucose oxidase/polyclonal anti-PSA detection antibody-modified gold nanoparticles (GOx-Au NP-dAb) were used as the immunoreaction platform and signal probe, respectively. Upon the addition of target PSA, a sandwiched immunocomplex was formed accompanying the immuno-recognition between the antigen and antibody, and then the carried GOx could oxidize glucose to produce H2O2. The photocurrent of the BaTiO3/Au nanocomposite-functionalized electrode amplified with increasing H2O2 concentration since H2O2 is considered as a good hole scavenger. On the basis of the above-mentioned mechanisms and the optimized conditions, the assembled PEC immunosensor was linear with the logarithm of the PSA concentration in the range of 0.01-40 ng mL-1 with a detection limit of 4.2 pg mL-1. It afforded rapid response, good precision, and high stability and specificity, implying its great promise in photoelectrochemical immunoassays. More generally, this system sets up an ideal PEC immunosensing system based on the BaTiO3/Au nanocomposites and represents an innovative and low-cost "signal-on" assay scheme for the practical quantitative screening of low-abundance proteins.


Assuntos
Compostos de Bário/química , Ouro/química , Calicreínas/sangue , Nanopartículas Metálicas/química , Antígeno Prostático Específico/sangue , Titânio/química , Anticorpos Monoclonais/imunologia , Compostos de Bário/efeitos da radiação , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Eletrodos , Glucose/análise , Glucose Oxidase/química , Ouro/efeitos da radiação , Humanos , Peróxido de Hidrogênio/química , Imunoensaio/métodos , Calicreínas/imunologia , Luz , Limite de Detecção , Nanopartículas Metálicas/efeitos da radiação , Nanocompostos/química , Nanocompostos/efeitos da radiação , Processos Fotoquímicos , Estudo de Prova de Conceito , Antígeno Prostático Específico/imunologia , Ressonância de Plasmônio de Superfície/métodos , Titânio/efeitos da radiação
8.
Analyst ; 144(21): 6352-6364, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31560361

RESUMO

The inclusion of nanoparticles (NP) in radiotherapy has been shown to increase the damaging effect on tumor cells. However, the mechanisms of action of NP combined with radiotherapy, and the influence of NP parameters and cell type on their radiosensitization capability at molecular and cellular levels still remain unclear. Gold NP (AuNP) have become particularly popular due to their multiple advantages. Within this context, our research work aimed to study the biochemical radiosensitization capacity of F98 and U87-MG glioma cell lines to 1.9 nm AuNP combined with X-ray irradiation. For this purpose, synchrotron-based infrared microspectroscopy (SR-FTIRM) was used as a powerful tool for biochemical composition and treatment response assessment of cells at a single-cell level. SR-FTIRM data, supported by multivariate analysis, revealed clear AuNP-induced changes in the DNA, protein and lipid spectral regions. The AuNP-related biochemical alterations appear prior to the irradiation, which gave us a first indication on the AuNP radiosensitization action. Biochemical modifications induced by the AuNP in the presence of radiotherapy irradiations include enhanced conformational changes in the protein secondary structures, variations in the intensity and position in the phosphodiester bands, and changes in the CH2 and CH3 stretching modes. These changes are better manifested at 24 hours post-irradiation time. SR-FTIRM results showed a clear heterogeneity in the biochemical cell response, probably due to the distinct cell-NP interactions and thus, to different DNA damage and cell death processes.


Assuntos
Glioma/metabolismo , Nanopartículas Metálicas/química , Radiossensibilizantes/farmacologia , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , DNA/metabolismo , Dano ao DNA/efeitos dos fármacos , Ouro/química , Ouro/efeitos da radiação , Humanos , Nanopartículas Metálicas/efeitos da radiação , Análise de Componente Principal , Proteínas/metabolismo , Radiossensibilizantes/química , Radiossensibilizantes/efeitos da radiação , Ratos , Espectrofotometria Infravermelho , Síncrotrons , Raios X
9.
Proc Natl Acad Sci U S A ; 116(37): 18590-18596, 2019 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-31451630

RESUMO

Biocompatible gold nanoparticles designed to absorb light at wavelengths of high tissue transparency have been of particular interest for biomedical applications. The ability of such nanoparticles to convert absorbed near-infrared light to heat and induce highly localized hyperthermia has been shown to be highly effective for photothermal cancer therapy, resulting in cell death and tumor remission in a multitude of preclinical animal models. Here we report the initial results of a clinical trial in which laser-excited gold-silica nanoshells (GSNs) were used in combination with magnetic resonance-ultrasound fusion imaging to focally ablate low-intermediate-grade tumors within the prostate. The overall goal is to provide highly localized regional control of prostate cancer that also results in greatly reduced patient morbidity and improved functional outcomes. This pilot device study reports feasibility and safety data from 16 cases of patients diagnosed with low- or intermediate-risk localized prostate cancer. After GSN infusion and high-precision laser ablation, patients underwent multiparametric MRI of the prostate at 48 to 72 h, followed by postprocedure mpMRI/ultrasound targeted fusion biopsies at 3 and 12 mo, as well as a standard 12-core systematic biopsy at 12 mo. GSN-mediated focal laser ablation was successfully achieved in 94% (15/16) of patients, with no significant difference in International Prostate Symptom Score or Sexual Health Inventory for Men observed after treatment. This treatment protocol appears to be feasible and safe in men with low- or intermediate-risk localized prostate cancer without serious complications or deleterious changes in genitourinary function.


Assuntos
Terapia a Laser/instrumentação , Nanopartículas Metálicas/administração & dosagem , Neoplasias da Próstata/cirurgia , Idoso , Estudos de Viabilidade , Seguimentos , Ouro/administração & dosagem , Ouro/efeitos da radiação , Humanos , Biópsia Guiada por Imagem/métodos , Raios Infravermelhos , Terapia a Laser/efeitos adversos , Terapia a Laser/métodos , Imagem por Ressonância Magnética Intervencionista/efeitos adversos , Imagem por Ressonância Magnética Intervencionista/instrumentação , Imagem por Ressonância Magnética Intervencionista/métodos , Masculino , Nanopartículas Metálicas/efeitos da radiação , Pessoa de Meia-Idade , Imagem Multimodal/efeitos adversos , Imagem Multimodal/instrumentação , Imagem Multimodal/métodos , Nanoconchas/administração & dosagem , Nanoconchas/efeitos da radiação , Oligopeptídeos , Órgãos em Risco/efeitos da radiação , Ereção Peniana/efeitos da radiação , Projetos Piloto , Próstata/diagnóstico por imagem , Próstata/patologia , Próstata/cirurgia , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Saúde Sexual , Ultrassonografia de Intervenção/efeitos adversos , Ultrassonografia de Intervenção/instrumentação , Ultrassonografia de Intervenção/métodos , Sistema Urogenital/efeitos da radiação
10.
Talanta ; 204: 548-554, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31357332

RESUMO

In this paper, a new strategy was presented for fluorescence labeling and imaging Al3+ in live cells with excess aluminum ions using thiolated fluorescence gold nanoclusters (Au NCs). The glutathione (GSH)-capped Au NCs were prepared via a green, facile one-pot method in aqueous solution and displayed excellent stability, ultrasmall size, monodispersity, and larger Stokes shift, which exhibits a relatively weak fluorescence at 650 nm Al3+-induced fluorescence enhancement of the GSH-Au NCs can be observed due to Al3+-triggered aggregation-induced emission (AIE) effect, which allows the role of GSH-Au NCs as a fluorescence light-up probe for detection of Al3+. Moreover, it was demonstrated that the fluorescence probe for Al3+ showed a wide detection range from 100 to 600 µM and good selectivity against other metal ions and common biomolecule. Furthermore, due to the advantages of excellent biocompatibility, low toxicity, red emission and high specificity, the proposed GSH-Au NCs fluorescence probes are suitable for the imaging of high concentrations of aluminum ions in cells, which can be applied to the diagnosis of cellular aluminum poisoning.


Assuntos
Alumínio/análise , Técnicas Biossensoriais/métodos , Corantes Fluorescentes/química , Glutationa/química , Ouro/química , Nanopartículas Metálicas/química , Linhagem Celular , Fluorescência , Corantes Fluorescentes/efeitos da radiação , Corantes Fluorescentes/toxicidade , Glutationa/toxicidade , Ouro/efeitos da radiação , Ouro/toxicidade , Humanos , Nanopartículas Metálicas/efeitos da radiação , Nanopartículas Metálicas/toxicidade , Raios Ultravioleta
11.
Analyst ; 144(8): 2820-2826, 2019 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-30882805

RESUMO

Developing a sensitive and selective detection platform of disease-related biomarkers is important for the diagnosis and treatment of diseases at an early stage. Among clinically meaningful biomarkers, proteins are the most commonly used indicators, and they are generally detected via immunoassays. However, the use of conventional immunoassays in early diagnosis is hindered by the time required, complex steps, high-cost, and insufficient sensitivity and selectivity. Herein, we developed a novel on-chip immunoassay with degassing-driven microfluidic devices and gold nanoplasmonic particles (GNPs). To recognize target proteins, antibody-conjugated GNPs as probes were used in the assay owing to their excellent scattering properties. Using the proposed nonenzymatic immunoassay, we detected amyloid ß (Aß) and Tau proteins, representative biomarkers of Alzheimer's disease, in femtomolar levels. Selective and quantitative detection of Aß spiked in blood plasma was also achieved for further clinical application of the proposed immunoassay. The proposed plasmonic immunoassay integrated with degassing-driven microfluidic chips provides a new platform for biological assays and diagnosis.


Assuntos
Peptídeos beta-Amiloides/sangue , Imunoensaio/métodos , Dispositivos Lab-On-A-Chip , Técnicas Analíticas Microfluídicas/métodos , Proteínas tau/análise , Peptídeos beta-Amiloides/imunologia , Anticorpos Monoclonais/imunologia , Ouro/química , Ouro/efeitos da radiação , Humanos , Limite de Detecção , Nanopartículas Metálicas/química , Nanopartículas Metálicas/efeitos da radiação , Técnicas Analíticas Microfluídicas/instrumentação , Proteínas tau/imunologia
12.
Carbohydr Polym ; 203: 378-385, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30318226

RESUMO

Although chemotherapy has been widely used in the treatment of many kinds of cancer, drug resistance and side effects are the main obstacles in the cancer chemotherapy that result in an inferior therapeutic outcome. For the design of drug delivery system, extracellular stability and intracellular effective release are also a pair of contradictions. In this research, gold nanorods (AuNRs) loaded hyaluronic acid (HA) nanogels with reduction sensitivity were prepared for the efficient intracellular delivery of doxorubicin (DOX). The aforementioned HA-CysNG@AuNR nanogels with cystamine (Cys) as crosslinker could remain stable in the physiological condition and release DOX rapidly in the mimic intracellular glutathione (GSH) condition. Meanwhile, the cellular uptake efficiency by the human breast carcinoma (MCF-7) cells was enhanced because of the highly expressed HA receptor (CD44) on the cytomembrane. However, further cell experiments verified that it was difficult to achieve desired results for drug-resistant human breast cancer (MCF-7 ADR) cells due to the reduced drug uptake and enhanced drug efflux. Interestingly, this multidrug resistance of MCF-7 ADR cells could be reversed after treated with near-infrared (NIR) light. This might ascribe to the hyperthermia generated by AuNRs under NIR, which suspended drug efflux process and led to excellent hyperthermia-assisted chemotherapy outcome. Overall, our studies suggested that AuNRs loaded reduction-sensitive HA nanogels were excellent candidates of drug carriers to reverse the drug-resistance and induce severe apoptosis of drug-resistant MCF-7 ADR cells.


Assuntos
Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Géis/química , Ácido Hialurônico/química , Antineoplásicos/química , Reagentes para Ligações Cruzadas/química , Cistamina/química , Doxorrubicina/química , Portadores de Fármacos/síntese química , Liberação Controlada de Fármacos , Géis/síntese química , Ouro/química , Ouro/efeitos da radiação , Calefação , Humanos , Ácido Hialurônico/síntese química , Raios Infravermelhos , Células MCF-7 , Nanotubos/química , Nanotubos/efeitos da radiação , Oxirredução
13.
Langmuir ; 34(49): 14891-14898, 2018 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-30407836

RESUMO

Novel RNA-based technologies provide an avenue of possibilities to control the regulation of gene expression in cells. To realize the full potential of small interfering RNA (siRNA)-based therapy, efficient delivery vehicles and novel strategies for triggering release from carrier vehicles have to be developed. Gold nanoparticles (AuNPs) with sizes of ∼50-150 nm have the ability to accumulate in tumor tissue and can be transported across the membrane by endocytosis. Therefore, a laser-controlled oligonucleotide release from such particles is of particular interest. Here, we quantify the loading of specifically attached microRNA oligonucleotides (miRNA) onto single gold nanoparticles with diameters of 80, 100, 150, and 200 nm. We show that AuNPs have a curvature-dependent density of miRNA loading: the higher the curvature, the higher the loading density. Moreover, we demonstrate how one sensing strand of an RNA duplex can be dehybridized and hence released from the AuNP by heating the AuNP by irradiation with a near-infrared (NIR) laser. Laser-induced release is also demonstrated inside living cells. Together, these findings show that plasmonic nanoparticles with high curvatures are ideal carriers of oligonucleotides into cells, and their cargo can be released in a controlled manner by a thermoplasmonic mechanism. Importantly, this remotely controlled release strategy can be applied to any cargo attached to a plasmonic nanocarrier, on either the single particle or ensemble level.


Assuntos
Portadores de Fármacos/química , Ouro/química , Lasers , Nanopartículas Metálicas/química , MicroRNAs/química , Carbocianinas/química , Portadores de Fármacos/efeitos da radiação , Portadores de Fármacos/toxicidade , Liberação Controlada de Fármacos , Corantes Fluorescentes/química , Ouro/efeitos da radiação , Ouro/toxicidade , Células HEK293 , Calefação , Humanos , Raios Infravermelhos , Nanopartículas Metálicas/efeitos da radiação , Nanopartículas Metálicas/toxicidade , MicroRNAs/genética , Hibridização de Ácido Nucleico/efeitos da radiação , Tamanho da Partícula
14.
J Am Chem Soc ; 140(49): 17226-17233, 2018 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-30452248

RESUMO

In this Article, we show that the surface of the bacteriophage Qß is equipped with natural ligands for the synthesis of small gold nanoparticles (AuNPs). By exploiting disulfides in the protein secondary structure and the geometry formed from the capsid quaternary structure, we find that we can produce regularly arrayed patterns of ∼6 nm AuNPs across the surface of the virus-like particle. Experimental and computational analyses provide insight into the formation and stability of this composite. We further show that the entrapped genetic material can hold upward of 500 molecules of the anticancer drug Doxorubicin without leaking and without interfering with the synthesis of the AuNPs. This direct nucleation of nanoparticles on the capsid allows for exceptional conduction of photothermal energy upon nanosecond laser irradiation. As a proof of principle, we demonstrate that this energy is capable of rapidly releasing the drug from the capsid without heating the bulk solution, allowing for highly targeted cell killing in vitro.


Assuntos
Allolevivirus/química , Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Ouro/química , Nanopartículas Metálicas/química , Células A549 , Animais , Antineoplásicos/química , Capsídeo/química , Proteínas do Capsídeo/química , Doxorrubicina/química , Portadores de Fármacos/efeitos da radiação , Portadores de Fármacos/toxicidade , Liberação Controlada de Fármacos , Ouro/efeitos da radiação , Ouro/toxicidade , Humanos , Hipertermia Induzida/métodos , Luz , Nanopartículas Metálicas/efeitos da radiação , Nanopartículas Metálicas/toxicidade , Camundongos , Tamanho da Partícula , Fototerapia/métodos , Porosidade , Estudo de Prova de Conceito , Células RAW 264.7 , RNA/química , RNA/toxicidade
15.
ACS Sens ; 3(11): 2261-2268, 2018 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-30350587

RESUMO

Loop-mediated isothermal amplification (LAMP) is a powerful gene amplification method, which has many advantages, including high specificity, sensitivity, and simple operation. However, quantitative analysis of the amplified target gene with the LAMP assay is very difficult. To overcome this limitation, we developed a novel biosensing platform for molecular diagnosis by integrating the LAMP method and retroreflective Janus particle (RJP) together. The final amplified products of the LAMP assay are dumbbell-shaped DNA structures, containing a single-stranded loop with two different sequences. Therefore, the concentration of the amplified products can be measured in a manner similar to the sandwich-type immunoassay. To carry out the sandwich-type molecular diagnostics using the LAMP product, two DNA probes, with complementary sequences to the loop-regions, were prepared and immobilized on both the sensing surface and the surface of the RJPs. When the amplified LAMP product was applied to the sensing surface, the surface-immobilized DNA probe hybridized to the loop-region of the LAMP product to form a double-stranded structure. When the DNA probe-conjugated RJPs were injected, the RJPs bound to the unreacted loop-region of the LAMP product. The number of RJPs bound to the loop-region of the LAMP product was proportional to the concentration of the amplified LAMP product, indicating that the concentration of the target gene can be quantitatively analyzed by counting the number of observed RJPs. Using the developed system, a highly sensitive and selective quantification of Salmonella was successfully performed with a detection limit of 102 CFU.


Assuntos
Técnicas de Tipagem Bacteriana/métodos , Técnicas Biossensoriais/métodos , Manufaturas , Imagem Óptica/métodos , Salmonella typhimurium/isolamento & purificação , Alumínio/química , Alumínio/efeitos da radiação , Sequência de Bases , Sondas de DNA/química , Sondas de DNA/genética , DNA Bacteriano/genética , DNA Complementar/genética , Ouro/química , Ouro/efeitos da radiação , Luz , Limite de Detecção , Microtecnologia , Técnicas de Amplificação de Ácido Nucleico , Hibridização de Ácido Nucleico , Fenômenos Ópticos , Dióxido de Silício/química , Dióxido de Silício/efeitos da radiação , Succinimidas/química
16.
Anal Chem ; 90(22): 13356-13364, 2018 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-30234969

RESUMO

Metallic plasmonic nanoparticles have been intensively exploited as theranostic nanoprobes for plasmonic photothermal therapy (PPT) and surface-enhanced Raman spectroscopy (SERS) applications. But the underlying molecular mechanisms associated with PPT-induced apoptosis between cancerous and normal cells have remained largely unknown or disputed. In this study, we designed an organelle-targeting theranostic plasmonic SERS nanoprobe (CDs-Ag/Au NS) composed of porous Ag/Au nanoshell (p-Ag/Au NSs) and carbon dots (CDs) for nucleus and mitochondria targeted PPT of cells. The differences in molecular stress response in the PPT-induced hyperthermia cell death between cancerous HeLa and normal L929 and H8 cells have been revealed by site-specific single-cell SERS detection. The contents of tryptophan (Trp), phenylalanine (Phe), and tyrosine (Tyr) in HeLa cells were found more evidently increased than L929 and H8 cells during the PPT-induced cell-death process. And from the mitochondria point of view, we found that the PPT-induced cell apoptosis for HeLa cells mainly stems from (or is regulated through) cellular thermal stress-responsive proteins, while for L929 and H8 cells it seems more related to DNA. Understanding molecular stress response difference of the PPT-induced cell apoptosis between cancerous and normal cells is helpful for diagnosis and treatment of cancer, and the method will open an avenue for single-cell studies.


Assuntos
Núcleo Celular/metabolismo , Mitocôndrias/metabolismo , Nanoconchas/química , Pontos Quânticos/química , Análise Espectral Raman/métodos , Nanomedicina Teranóstica/métodos , Apoptose/efeitos dos fármacos , Carbono/química , Carbono/efeitos da radiação , Peptídeos Penetradores de Células/química , Peptídeos Penetradores de Células/metabolismo , DNA/metabolismo , Fragmentação do DNA/efeitos dos fármacos , Ouro/química , Ouro/efeitos da radiação , Células HeLa , Humanos , Hipertermia Induzida/métodos , Raios Infravermelhos , Nanoconchas/efeitos da radiação , Neoplasias/metabolismo , Sinais de Localização Nuclear/química , Sinais de Localização Nuclear/metabolismo , Pontos Quânticos/efeitos da radiação , Prata/química , Prata/efeitos da radiação
17.
Langmuir ; 34(49): 14946-14953, 2018 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-30075633

RESUMO

DNA is a powerful tool to assemble gold nanoparticles into discrete structures with tunable plasmonic properties for photonic or biomedical applications. Because of their photothermal properties or their use in biological media, these nanostructures can experience drastic modifications of the local temperature that can affect their morphology and, therefore, their optical responses. Using single-nanostructure spectroscopy, we demonstrate that, even with a fully stable DNA linker, gold particle dimers can undergo substantial conformational changes at temperatures larger than 50 °C and aggregate irreversibly. Such temperature-dependent resonant optical properties could find applications in imaging and in the design of nonlinear photothermal sources. Inversely, to provide fully stable DNA-templated plasmonic nanostructures at biologically relevant temperatures, we show how passivating the gold nanoparticles using amphiphilic surface chemistries renders the longitudinal plasmon resonance of gold particle dimers nearly independent of the local temperature.


Assuntos
DNA/química , Ouro/química , Nanopartículas Metálicas/química , Sequência de Bases , DNA/genética , Ouro/efeitos da radiação , Interações Hidrofóbicas e Hidrofílicas , Nanopartículas Metálicas/efeitos da radiação , Microscopia/métodos , Hibridização de Ácido Nucleico , Tamanho da Partícula , Polietilenoglicóis/química , Análise Espectral/métodos , Propriedades de Superfície , Tensoativos/química , Temperatura
18.
Environ Sci Pollut Res Int ; 25(25): 25401-25412, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29951757

RESUMO

In this work, natural sunlight successfully induced the deposition of gold (Au), silver (Ag), and palladium (Pd) nanoparticles (NPs) with 17.10, 9.07, and 12.70 wt% onto the surface of graphitic carbon nitride (g-C3N4). The photocatalytic evaluation was carried out by adopting Bisphenol A (BPA) as a pollutant under natural sunlight irradiation. The presence of noble metals was confirmed by EDX, HRTEM, and XPS analysis. The deposition of Ag NPs (7.9 nm) resulted in the degradation rate which was 2.15-fold higher than pure g-C3N4 due to its relatively small particle size, contributing to superior charge separation efficiency. Au/g-C3N4 unveiled inferior photoactivity because the LSPR phenomenon provided two pathways for electron transfer between Au NPs and g-C3N4 further diminished the performance. The improved degradation lies crucially on the particle size and Schottky barrier formation at the interface of M/g-C3N4 (M=Au, Ag, and Pd) but not the visible light harvesting properties. The mechanism insight revealed the holes (h+) and superoxide radical (•O2-) radical actively involved in photocatalytic reaction for all composites.


Assuntos
Compostos Benzidrílicos , Ouro/efeitos da radiação , Nitrilos/química , Paládio/efeitos da radiação , Fenóis , Prata/efeitos da radiação , Luz Solar , Poluentes Químicos da Água/efeitos da radiação , Catálise , Grafite/química , Luz , Nanopartículas , Tamanho da Partícula , Ressonância de Plasmônio de Superfície
19.
Nature ; 556(7701): 360-365, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29670265

RESUMO

Understanding chirality, or handedness, in molecules is important because of the enantioselectivity that is observed in many biochemical reactions 1 , and because of the recent development of chiral metamaterials with exceptional light-manipulating capabilities, such as polarization control2-4, a negative refractive index 5 and chiral sensing 6 . Chiral nanostructures have been produced using nanofabrication techniques such as lithography 7 and molecular self-assembly8-11, but large-scale and simple fabrication methods for three-dimensional chiral structures remain a challenge. In this regard, chirality transfer represents a simpler and more efficient method for controlling chiral morphology12-18. Although a few studies18,19 have described the transfer of molecular chirality into micrometre-sized helical ceramic crystals, this technique has yet to be implemented for metal nanoparticles with sizes of hundreds of nanometres. Here we develop a strategy for synthesizing chiral gold nanoparticles that involves using amino acids and peptides to control the optical activity, handedness and chiral plasmonic resonance of the nanoparticles. The key requirement for achieving such chiral structures is the formation of high-Miller-index surfaces ({hkl}, h ≠ k ≠ l ≠ 0) that are intrinsically chiral, owing to the presence of 'kink' sites20-22 in the nanoparticles during growth. The presence of chiral components at the inorganic surface of the nanoparticles and in the amino acids and peptides results in enantioselective interactions at the interface between these elements; these interactions lead to asymmetric evolution of the nanoparticles and the formation of helicoid morphologies that consist of highly twisted chiral elements. The gold nanoparticles that we grow display strong chiral plasmonic optical activity (a dis-symmetry factor of 0.2), even when dispersed randomly in solution; this observation is supported by theoretical calculations and direct visualizations of macroscopic colour transformations. We anticipate that our strategy will aid in the rational design and fabrication of three-dimensional chiral nanostructures for use in plasmonic metamaterial applications.


Assuntos
Aminoácidos/química , Técnicas de Química Sintética/métodos , Ouro/química , Nanopartículas Metálicas/química , Peptídeos/química , Dicroísmo Circular , Cisteína/química , Ouro/efeitos da radiação , Luz , Nanopartículas Metálicas/efeitos da radiação , Rotação Ocular , Fotometria , Estereoisomerismo
20.
J Hazard Mater ; 347: 378-389, 2018 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-29407847

RESUMO

Sunlight mediated photo-degradation and anti-bacterial activity of hetero junctioned plasmonic binary (Au/ZnO, RGO/ZnO) and ternary (RGO/Au/ZnO) nanocomposites (NC) have been reported. Higher photo-charge carrier generation, increased charge separation, improved active sites for catalysis, enhanced LSPR and larger photo-response regions have been achieved. Decoration with Au nanoparticles (ca. 11 ±â€¯3 and 48 ±â€¯5 nm) and RGO of ZnO (3D/1D) microstructures (aspect ratio 15.18) provides ternary NCs an edge over mono/bi component catalysts. The ternary NC have shown improved dye degradation capacity with 100% efficiency (5 µM MB solution) and average adsorption degradation capacity (Q°) of 83.34 mg/g within 30 min of sunlight exposure (900 ±â€¯30 Wm-2). Elaborated studies by varying reaction parameters like initial dye concentration, contact time, type of NCs and initial loading of NCs reveals pseudo first order degradation kinetics. 100% microbial killing of Gram positive S.aureus strain with 60 µg/ml of NC using sunlight as activator has proven the simultaneous multiple functionality of the NC. Further, facile green one pot hydrothermal synthesis with water as reaction medium, absence of photo-corrosion of NCs, regeneration ability (ca. 90% for 10 µM solution) of NCs, projects a broader potential application of the synthesized NCs and could reduce the continuous requirement of such material, limiting the environmental toxicity.


Assuntos
Ouro , Grafite , Nanocompostos , Óxido de Zinco , Catálise , Corantes/química , Ouro/administração & dosagem , Ouro/química , Ouro/efeitos da radiação , Grafite/administração & dosagem , Grafite/química , Grafite/efeitos da radiação , Azul de Metileno/química , Nanocompostos/administração & dosagem , Nanocompostos/química , Nanocompostos/efeitos da radiação , Nanocompostos/ultraestrutura , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/efeitos da radiação , Luz Solar , Poluentes Químicos da Água/química , Purificação da Água/métodos , Óxido de Zinco/administração & dosagem , Óxido de Zinco/química , Óxido de Zinco/efeitos da radiação
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