The effect of the pH on the interaction of L-arginine with colloidal silver nanoparticles. A Raman and SERS study
Author
dc.contributor.author
Garrido, C.
Author
dc.contributor.author
Aguayo, T.
es_CL
Author
dc.contributor.author
Clavijo Campos, Ernesto
es_CL
Author
dc.contributor.author
Gómez Jeria, Juan
es_CL
Author
dc.contributor.author
Campos Vallette, Marcelo
es_CL
Admission date
dc.date.accessioned
2014-01-28T18:56:11Z
Available date
dc.date.available
2014-01-28T18:56:11Z
Publication date
dc.date.issued
2013
Cita de ítem
dc.identifier.citation
J. Raman Spectrosc. 2013, 44, 1105 – 1110
en_US
Identifier
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DOI 10.1002/jrs.4331
Identifier
dc.identifier.uri
https://repositorio.uchile.cl/handle/2250/119724
General note
dc.description
Artículo de publicación ISI
en_US
Abstract
dc.description.abstract
Raman and surface enhanced Raman scattering (SERS) spectroscopies were used to study the pH effect (7 to 9) on the
interaction of arginine (Arg) with colloidal Ag nanoparticles (AgNps). A new methodology was implemented in order to obtain
reproducible SERS spectra in solution. The dependence of the Arg concentration on the stability of the AgNps is discussed. A
pH increasing of the colloidal solution to the limits of the Arg pKa2 value induces a preferential and stable Arg–metal
interaction. j potential measurements of the Arg–AgNps system at different pH conditions studied provide information about
the Arg–AgNps interaction; the pH increasing favors the interaction. SERS spectra at pH 7 indicate that the molecule interacts
with the Ag surface only through the guanidinium fragment. By increasing the pH to 9, the molecule adopts a new
conformation on the surface; the metal–analyte interaction is verified through the guanidinium, carboxylate and the aliphatic
moieties. In addition, theoretical calculations performed by using the extended Hückel method for a model of Arg interacting
with an Ag surface support the observed SERS results.