Busca avançada
Ano de início
Entree
(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

SERS active self-assembled diphenylalanine micro/nanostructures: A combined experimental and theoretical investigation

Texto completo
Autor(es):
Kogikoski, Jr., Sergio ; Khanra, Soma ; Alves, Wendel A. ; Guha, Suchismita
Número total de Autores: 4
Tipo de documento: Artigo Científico
Fonte: Journal of Chemical Physics; v. 147, n. 8 AUG 28 2017.
Citações Web of Science: 4
Resumo

Enhancing Raman signatures of molecules by self-assembled metal nanoparticles, nanolithography patterning, or by designing plasmonic nanostructures is widely used for detection of low abundance biological systems. Self-assembled peptide nanostructures provide a natural template for tethering Au and Ag nanoparticles due to its fractal surface. Here, we show the use of L, L-diphenylalanine micro-nanostructures (FF-MNSs) for the organization of Ag and Au nanoparticles (Nps) and its potential as surface-enhanced Raman scattering (SERS)-active substrates. The FF-MNSs undergo an irreversible phase transition from hexagonally packed (hex) micro-nanotubes to an orthorhombic (ort) structure at similar to 150 degrees C. The metal Nps form chains on hex FF-MNSs as inferred from transmission electron microscopy images and a uniform non-aggregated distribution in the ort phase. The high luminescence from the ort FF-MNS phase precludes SERS measurements with AgNps. The calculated Raman spectra using density-functional theory shows a higher intensity from rhodamine 6G (R6G) molecule in the presence of an Ag atom bound to ort FF compared with hex FF. The SERS spectra obtained from R6G bound to FF-MNSs with AuNps clearly show a higher enhancement for the ort phase compared with hex FF, corroborating our theoretical calculations. Our results indicate that FF-MNSs both in the hex and ort phases can be used as substrates for the SERS analysis with different metal nanoparticles, opening up a novel class of optically active bio-based substrates. Published by AIP Publishing. (AU)

Processo FAPESP: 16/14507-8 - Estudos das propriedades estruturais e eletroquímicas de filmes nanoestruturados baseados em DNA
Beneficiário:Sergio Kogikoski Junior
Linha de fomento: Bolsas no Brasil - Pós-Doutorado
Processo FAPESP: 12/01933-8 - Matrizes biomiméticas obtidas por eletrofiação: possível aplicação na detecção de NO
Beneficiário:Sergio Kogikoski Junior
Linha de fomento: Bolsas no Brasil - Doutorado Direto
Processo FAPESP: 15/24018-1 - Conjugados polímero-peptídeo para formulação de hidrogéis e seu uso em detecção
Beneficiário:Wendel Andrade Alves
Linha de fomento: Auxílio à Pesquisa - Regular