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1.
ACS Nano ; 14(1): 28-117, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31478375

RESUMO

The discovery of the enhancement of Raman scattering by molecules adsorbed on nanostructured metal surfaces is a landmark in the history of spectroscopic and analytical techniques. Significant experimental and theoretical effort has been directed toward understanding the surface-enhanced Raman scattering (SERS) effect and demonstrating its potential in various types of ultrasensitive sensing applications in a wide variety of fields. In the 45 years since its discovery, SERS has blossomed into a rich area of research and technology, but additional efforts are still needed before it can be routinely used analytically and in commercial products. In this Review, prominent authors from around the world joined together to summarize the state of the art in understanding and using SERS and to predict what can be expected in the near future in terms of research, applications, and technological development. This Review is dedicated to SERS pioneer and our coauthor, the late Prof. Richard Van Duyne, whom we lost during the preparation of this article.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 196: 222-228, 2018 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-29453097

RESUMO

Self-assembled multi-layered vertically aligned gold nanorod (AuNR) arrays have been fabricated by a simple preparation process that requires a balance between the particle concentration and the ionic strength of the solvent. An experimentally determined critical AuNR concentration of 2.0nM and 50mM NaCl produces well-ordered vertically aligned hexagonally close-packed AuNR arrays. We demonstrate surface treatment via UV Ozone cleaning of such samples to allow introduction of analyte molecules (benzenethiol and cannabinol) for effective surface enhanced Raman scattering detection. This is the first demonstration of the SERS analysis of cannabinol. This approach demonstrates a cost-effective, high-yield and simple fabrication route to SERS sensors with application in the screening for the cannabinoids.


Assuntos
Canabinol/análise , Ouro/química , Nanotubos/química , Análise Espectral Raman/métodos , Fenóis/análise , Cloreto de Sódio/química , Compostos de Sulfidrila/análise
3.
Chem Commun (Camb) ; 48(7): 1024-6, 2012 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-22158658

RESUMO

Silica-encapsulated Raman-reporter embedded SERS nanoprobes, named nanoaggregate embedded beads (NAEBs), were conjugated to the Salmonella specific tailspike protein (TSP) isolated from the P22 bacteriophage to enable a highly specific and ultrasensitive optical transduction platform. We demonstrate three successful surface conjugation strategies and highlight the detection of a single bacterium using SERS.


Assuntos
Bacteriófago P22/química , Técnicas Biossensoriais/métodos , Salmonella/isolamento & purificação , Dióxido de Silício/química , Análise Espectral Raman/métodos , Proteínas da Cauda Viral/química , Humanos , Nanoestruturas/química , Infecções por Salmonella/diagnóstico , Sensibilidade e Especificidade
4.
Chem Commun (Camb) ; 48(4): 561-3, 2012 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-22068209

RESUMO

The synthesis of magnetic and fluorescent particles is described. The particles are biofunctionalized by binding pathogen-specific proteins to the particles via interactions between His-tags of proteins and zinc of the quantum dots. Detection of Salmonella and Staphylococcus aureus (S. aureus) by these particles is demonstrated.


Assuntos
Corantes Fluorescentes/química , Imãs/química , Pontos Quânticos , Salmonella/isolamento & purificação , Staphylococcus aureus/isolamento & purificação , Corantes Fluorescentes/síntese química , Microscopia de Força Atômica
5.
Analyst ; 136(8): 1620-6, 2011 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-21369597

RESUMO

Brain injury can lead to irreversible tissue loss and functional deficit along with significant health care costs. Raman spectroscopy can be used as a non-invasive technique to provide detailed information on the molecular composition of diseased and damaged tissues. This technique was used to examine acute mouse brain injury, focusing on the motor cortex, a region directly involved in controlling execution of movement. The spectral profile obtained from the injured brain tissue revealed a markedly different signature, particularly in the amide I and amide III vibrational region when compared to that of healthy brain tissue. Most noticeably, there was a significant reduction of the amide I vibration at the acute injury site and the appearance of two distinct features at 1586 and 1618 cm(-1). Complementary immunohistochemical analysis of the injured brain tissue showed an abundant expression of Caspase 3 (a cysteine protease marker used for apoptosis), suggesting that the injury-induced specific Raman shifts may be correlated with cell death. Taken together, this study demonstrates that Raman spectroscopy can play an important role in detecting the changes that occur in the injured brain and provide a possible technology for monitoring the recovery process.


Assuntos
Lesões Encefálicas/patologia , Análise Espectral Raman/métodos , Amidas/química , Animais , Lesões Encefálicas/enzimologia , Caspase 3/metabolismo , Análise Discriminante , Camundongos , Análise de Componente Principal
6.
Chem Commun (Camb) ; 47(11): 3156-8, 2011 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-21279194

RESUMO

Silver nanoparticles bonded to terminal alkynes form stable particles in aqueous solution, produce strong SERS signals for molecular imaging that arise from the carbon-metal bond, and expand the scope of molecules that can be used to stably functionalize plasmonic particles for mammalian cell imaging applications. ß-Lactams represent a class of biologically important molecules that can be adapted to SERS studies in this manner.


Assuntos
Alquinos/química , Carbono/química , Nanopartículas Metálicas/química , Prata/química , Linhagem Celular Tumoral , Humanos , Ligantes , Proteínas de Membrana/análise , Ocludina , Análise Espectral Raman , beta-Lactamas/química
7.
Nanoscale ; 2(8): 1413-6, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20820725

RESUMO

Multiplexed SERS imaging of receptor proteins on the surface of mammalian cells has been carried out using functionalized silver nanoparticles. Deconvolution of four differently functionalized nanoparticles is readily achieved, and using this approach, receptor co-localization can be probed and protein-protein interactions can be elucidated at the surface of cells.


Assuntos
Proteínas de Membrana/química , Nanopartículas Metálicas/química , Animais , Caveolina 3/química , Ligantes , Nanopartículas Metálicas/ultraestrutura , Microscopia Confocal , Miócitos Cardíacos/citologia , Ratos , Receptores Adrenérgicos beta 2/química , Prata/química , Análise Espectral Raman
8.
Chem Commun (Camb) ; (44): 6750-2, 2009 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-19885467

RESUMO

Water-soluble carborane functionalized nanoparticles also co-functionalized with targeting antibodies have been prepared. We demonstrate tumour cell targeting with anti-EGFR antibodies and delivery of a high concentration of boron using SERS imaging. This suggests these materials have a therapeutic potential in addition to multimodal imaging capabilities.


Assuntos
Anticorpos Antineoplásicos/uso terapêutico , Boro/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Receptores ErbB/imunologia , Linhagem Celular Tumoral , Humanos , Nanopartículas/administração & dosagem , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico , Análise Espectral Raman
9.
Bioconjug Chem ; 20(10): 1966-74, 2009 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-19751063

RESUMO

Because antibodies are highly target-specific and nanoparticles possess diverse, material-dependent properties that can be exploited in order to label and potentially identify biomolecules, the development of antibody-nanoparticle conjugates (nanoconjugates) has huge potential in biodiagnostics. Here, we describe a novel superparamagnetic nanoconjugate, one whose recognition component is a single-domain antibody. It is highly active toward its target Staphylococcus aureus, displays long shelf life, lacks cross-reactivity inherent to traditional homologue whole antibodies, and captures a few dozen S. aureus cells in a mixed cell population with ~100% efficiency and specificity. We ascribe the excellent performance of our nanoconjugate to its single-domain antibody component and recommend it as a general purpose recognition element.


Assuntos
Anticorpos Antibacterianos/química , Técnicas Bacteriológicas/métodos , Compostos Férricos/química , Nanopartículas de Magnetita , Dióxido de Silício/química , Staphylococcus aureus/isolamento & purificação , Anticorpos Antibacterianos/imunologia , Nanopartículas de Magnetita/química , Nanoconjugados , Estrutura Terciária de Proteína , Salmonella , Sensibilidade e Especificidade , Infecções Estafilocócicas/diagnóstico , Staphylococcus aureus/imunologia
10.
ACS Nano ; 3(8): 2329-39, 2009 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-19702324

RESUMO

Adrenergic signaling that controls the contraction of cardiac myocyte cells and the beating of the mammalian heart is initiated by ligand binding to adrenergic receptors contained in nanoscale multiprotein complexes at the cellular membrane. Here we demonstrate that the surface-enhanced Raman scattering (SERS) of functionalized silver nanoparticles can be used to report on the receptor aggregation state of specifically label beta(2)-adrenergic receptors on mouse cardiac myocyte cells. Furthermore, multimodal imaging including Raman, Rayleigh scattering, scanning electron microscopy, and luminescence imaging was combined to fully characterize the beta(2)-adrenergic receptor-mediated aggregation of silver nanoparticles on the membrane of cardiac myocytes. Scanning electron microscopy analysis reveals distinct SERS active clusters of between 10 and 70 nanoparticles per signaling domain from ultra-high-resolution images of beta(2)-adrenergic receptor clusters on the cellular membrane. These techniques can be generally applied to study the aggregation of other cell surface receptors and explore their distribution on cell surfaces.


Assuntos
Nanopartículas Metálicas/análise , Células Musculares/química , Receptores Adrenérgicos beta 2/análise , Prata/química , Análise Espectral Raman/métodos , Animais , Linhagem Celular , Membrana Celular/química , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Camundongos , Microscopia Eletrônica de Varredura , Microscopia de Fluorescência , Modelos Moleculares , Estrutura Molecular , Células Musculares/metabolismo , Receptores Adrenérgicos beta 2/química , Receptores Adrenérgicos beta 2/metabolismo
12.
Org Biomol Chem ; 5(15): 2380-9, 2007 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-17637957

RESUMO

Raman and coherent anti-Stokes Raman scattering (CARS) microscopies have the potential to aid in detailed longitudinal studies of RNA localization. Here, we evaluate the use of carbon-deuterium and benzonitrile functional group labels as contrast agents for vibrational imaging of hepatitis C virus (HCV) replicon RNA. Dynamic light scattering and atomic force microscopy were used to evaluate the structural consequences of altering HCV subgenomic replicon RNA. Modification with benzonitrile labels caused the replicon RNA tertiary structure to partially unfold. Conversely, deuterium-modified replicon RNA was structurally similar to unmodified replicon RNA. Furthermore, the deuterated replicon RNA provided promising vibrational contrast in Raman imaging experiments. The functional effect of modifying subgenomic HCV replicon RNA was evaluated using the luciferase gene as a genetic reporter of translation. Benzonitrile labeling of the replicon RNA prevented translation in cell-based luciferase assays, while the deuterated replicon RNA retained both translation and replication competency. Thus, while the scattering cross-section for benzonitrile labels was higher, only carbon-deuterium labels proved to be non-perturbative to the function of HCV replicon RNA.


Assuntos
Hepacivirus/genética , Sondas Moleculares/química , RNA Viral/análise , RNA Viral/química , Coloração e Rotulagem/métodos , Fenômenos Biofísicos , Biofísica , Linhagem Celular Tumoral , Meios de Contraste , Genoma Viral/genética , Humanos , Microscopia , Nitrilos/química , Replicon/genética , Análise Espectral Raman , Uridina/genética , Vibração
13.
Bioorg Chem ; 35(3): 284-93, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17316745

RESUMO

A recombinant VH single-domain antibody recognizing staphylococcal protein A was functionalized on reactive lysine residues with N-hydroxysuccimidyl-activated 4-cyanobenzoate. Surface plasmon resonance analysis of antibody-antigen binding revealed that modified and unmodified antibodies bound protein A with similar affinities. Raman imaging of the modified antibodies indicated that the benzonitrile group provides vibrational contrast enhancement in a region of the electromagnetic spectrum that is transparent to cellular materials. Thus, the modified single-domain antibody may be amenable to detecting protein A from samples of the human pathogen Staphylococcus aureus using vibronic detection schemes such as Raman and coherent anti-Stokes Raman scattering. The generality of this labeling strategy should make it applicable to modifying an array of proteins with varied structure and function.


Assuntos
Benzoatos/química , Benzoatos/síntese química , Proteína Estafilocócica A/química , Reações Antígeno-Anticorpo , Benzoatos/farmacologia , Estrutura Molecular , Estrutura Terciária de Proteína , Sensibilidade e Especificidade , Soroalbumina Bovina/química , Soroalbumina Bovina/efeitos dos fármacos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Análise Espectral Raman/métodos , Proteína Estafilocócica A/efeitos dos fármacos , Staphylococcus aureus/química , Staphylococcus aureus/efeitos dos fármacos , Relação Estrutura-Atividade , Succinimidas/química , Ressonância de Plasmônio de Superfície/métodos , Vibração
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