Self-assembled gold nanoparticles and amphiphile peptides: a colorimetric probe for copper(ii) ion detection

Autor(es)

Pelin, Juliane N. B. D. ^{[1, 2]} ; Edwards-Gayle, Charlotte J. C. ^[2] ; Martinho, Herculano ^[1] ; Gerbelli, Barbara B. ^[1] ; Castelletto, Valeria ^[2] ; Hamley, Ian W. ^[2] ; Alves, Wendel A. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Fed ABC, Ctr Ciencias Nat & Humanas, BR-09210580 Santo Andre, SP - Brazil

^[2] Univ Reading, Dept Chem, Reading RG6 6AD, Berks - England

• Tipo de documento: Artigo Científico
• Fonte: DALTON TRANSACTIONS; v. 49, n. 45, p. 16226-16237, DEC 7 2020.
• Citações Web of Science: 1

Resumo

Morphological, spectroscopic and scattering studies of the self-assembly and aggregation process of hybrids containing gold nanoparticles (AuNPs) and the amyloid peptides {[}RF](4) and P{[}RF](4) (where R = arginine; F = phenylalanine; P = proline) in aqueous solution were performed. Two methodologies were tested for the AuNP nucleation, using sodium borohydride (NaBH4) or epigallocatechin gallate (EGCG) as a reducing agent. This led to remarkable distinct modes of assembly, AuNP decorated fibrils with NaBH4 reduction or isolated AuNPs with EGCG reduction. For both methodologies, the presence of spherical AuNPs was observed by plasmonic resonance bands in absorption spectra at similar to 520 nm. Zeta potential measurements confirmed stable systems, with a similar aggregation state. Circular dichroism spectra revealed an antiparallel beta-sheet conformation of the peptides. The transmission electron microscopy (TEM) images showed the coexistence of nanometer fibers and globular nanoparticles with 20 nm size. The small-angle X-ray scattering (SAXS) results show that the NaBH4 systems presented large cylindrical structures, while with increasing P{[}RF](4) content, a decrease in radius was observed. However, the EGCG-AuNPs were characterized by spherical particles, with a radius of 10-20 nm. Also, the colorimetric efficiency of the hybrids in the capture of Cu2+ ions in solution was monitored. Raman spectroscopy data confirmed the conformation/structure of self-assembled samples. Moreover, there are indications for a surface-enhanced Raman spectroscopy (SERS) effect for Cu2+ sites. The set of results indicates that these systems could act as a promising sensitive metal concentration probes. (AU)

• Processo FAPESP: 18/05888-3 - Biossensores baseados em peptídeos anfifílicos para detecção e diagnóstico de doenças
• Beneficiário: Barbara Bianca Gerbelli
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 15/20446-9 - Estudo da auto-organização de estruturas hierárquicas de peptídeos em solução em presença de nanopartículas metálicas
• Beneficiário: Juliane Nogueira Batista Dias Pelin
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto
• Processo FAPESP: 18/12535-0 - Estudo da auto-organização de estruturas hierárquicas de peptídeos em solução em presença de nanopartículas metálicas
• Beneficiário: Juliane Nogueira Batista Dias Pelin
• Modalidade de apoio: Bolsas no Exterior - Estágio de Pesquisa - Doutorado Direto
• Processo FAPESP: 17/02317-2 - Interfaces em materiais: propriedades eletrônicas, magnéticas, estruturais e de transporte
• Beneficiário: Adalberto Fazzio
• Modalidade de apoio: Auxílio à Pesquisa - Temático