Direct optical detection of aptamer conformational changes induced by target molecules.
Anal Chem
; 81(24): 10002-6, 2009 Dec 15.
Article
em En
| MEDLINE
| ID: mdl-19928834
ABSTRACT
Aptamers are single-stranded DNA/RNA oligomers that fold into three-dimensional conformations in the presence of specific molecular targets. Surface-enhanced Raman spectroscopy (SERS) of thiol-bound DNA aptamer self-assembled monolayers on Au nanoshell surfaces provides a direct, label-free detection method for the interaction of DNA aptamers with target molecules. A spectral cross-correlation function, Gamma, is shown to be a useful metric to quantify complex changes in the SERS spectra resulting from conformational changes in the aptamer induced by target analytes. While the pristine, unexposed anti-PDGF (PDGF = platelet-derived growth factor) aptamer yields highly reproducible spectra with Gamma = 0.91 +/- 0.01, following incubation with PDGF, the reproducibility of the SERS spectra is dramatically reduced, yielding Gamma = 0.67 +/- 0.02. This approach also allows us to discriminate the response of a cocaine aptamer to its target from its weaker response to nonspecific analyte molecules.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Fator de Crescimento Derivado de Plaquetas
/
Cocaína
/
Aptâmeros de Nucleotídeos
Tipo de estudo:
Diagnostic_studies
Idioma:
En
Ano de publicação:
2009
Tipo de documento:
Article