English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/161467
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar a otros formatos:


Large size citrate-reduced gold colloids appear as optimal SERS substrates for cationic peptides

AuthorsLópez-Tobar, Eduardo ; Hernández, Belén; Chenal, Alexandre; Coic, Y. M.; Gómez Santos, J.; Mejía-Ospino, E.; García-Ramos, José Vicente ; Ghomi, Mahmoud; Sánchez-Cortés, Santiago
KeywordsSurface-enhance Raman spectroscopy plasmonic nanoparticles
Transmission electron microscopy
UV-visible absorption
Citrate-reduced gold colloids
Issue Date5-Jul-2016
PublisherJohn Wiley & Sons
CitationJournal of Raman Spectroscopy 48: 30-37 (2017)
AbstractSurface-enhanced Raman spectra of two cyclic cationic peptides with therapeutic interest, somatostatin-14 and its synthetic analog octreotide, were simultaneously analyzed as a function of concentration and colloidal size. It appeared that the large size (~95 nm) citrate-reduced gold nanoparticles are the most adequate substrates for providing an optimal Raman signal enhancement within the 10–10 m peptide concentration range. It could also be evidenced that these large size particles can give rise to such a remarkable result within the first month following their elaboration. In fact, the recorded Raman spectra after this period mainly originate from the molecular species in the coverage of gold particles and not from the adsorbed peptides. To bring clarification to the temporal evolution of gold colloids, a systematic analysis was performed during 3 months on different particle sizes in the 15–150 nm range. The data obtained by a combined use of different techniques (Ultraviolet-visible absorption, z-potential, transmission electron microscopy, and Raman scattering) are consistent with a permanent evolution of the colloidal coverage, assignable to the gradual transformation of citrate anions and their substitution by oxidized products. It can be concluded that only small and medium size nanoparticles (≤ 40 nm) are able to regenerate their initial features after the first month, while large size colloids are subjected to a continuous degradation of their plasmonic and electrostatic properties. Copyright © 2016 John Wiley & Sons, Ltd.
Description8 pags., 5 figs., 2 tabs.
Publisher version (URL)http://doi.org/10.1002/jrs.4976
Identifiersdoi: 10.1002/jrs.4976
issn: 1097-4555
Appears in Collections:(CFMAC-IEM) Artículos
Files in This Item:
File Description SizeFormat 
accesoRestringido.pdf15,38 kBAdobe PDFThumbnail
Show full item record
Review this work

Related articles:

WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.