Tracking chemical interactions of folic acid on gold surface by SERS spectroscopy.
Spectrochim Acta A Mol Biomol Spectrosc
; 223: 117305, 2019 Dec 05.
Article
em En
| MEDLINE
| ID: mdl-31255863
ABSTRACT
Surface-enhanced Raman scattering (SERS) spectroscopy was used in the investigation of the adsorption of folic acid (FA) on the surface of gold nanoparticles (AuNPs) in the absence and presence of surface modifiers hydrochloride acid (HCl) and 1-mercaptoethanol (ME). The proposal for the chemical interactions of FA with the metallic surface was based on vibrational assignment supported by Density Functional Theory (DFT) calculations. In the absence of surface modifiers, FA interacts with the gold surface through the pteridine moiety in a tilted geometry. In the presence of ME, the molecule of FA is anchored through hydrogen bonds with the surface modifier. The presence of HCl induced ion-pair interactions involving chloride ions, adsorbed on gold surfaces, and both the nitrogen N1 of the pteridine ring and the γ-carboxylic acid of the glutamic acid moiety. In this condition, keto-enol equilibrium can be evidenced by a remarkable enhancement of marker bands in the SERS spectra.
Texto completo:
1
Base de dados:
MEDLINE
Idioma:
En
Revista:
Spectrochim Acta A Mol Biomol Spectrosc
Assunto da revista:
BIOLOGIA MOLECULAR
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Brasil