Interfacial electrical properties of DNA-modified diamond thin films: intrinsic response and hybridization-induced field effects.
Langmuir
; 20(16): 6778-87, 2004 Aug 03.
Article
em En
| MEDLINE
| ID: mdl-15274585
ABSTRACT
We have investigated the frequency-dependent interfacial electrical properties of nanocrystalline diamond films that were covalently linked to DNA oligonucleotides and how these properties are changed upon exposure to complementary and noncomplementary DNA oligonucleotides. Frequency-dependent electrical measurements at the open-circuit potential show significant changes in impedance at frequencies of >10(4) Hz when DNA-modified diamond films are exposed to complementary DNA, with only minimal changes when exposed to noncomplementary DNA molecules. Measurements as a function of potential show that at 10(5) Hz, the impedance is dominated by the space-charge region of the diamond film. DNA molecules hybridizing at the interface induce a field effect in the diamond space-charge layer, altering the impedance of the diamond film. By identifying a range of impedances where the impedance is dominated by the diamond space-charge layer, we show that it possible to directly observe DNA hybridization, in real time and without additional labels, via simple measurement of the interfacial impedance.
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Base de dados:
MEDLINE
Assunto principal:
Oligonucleotídeos
/
DNA
/
Diamante
/
Nanoestruturas
/
Membranas Artificiais
Tipo de estudo:
Diagnostic_studies
Idioma:
En
Ano de publicação:
2004
Tipo de documento:
Article