An FET-type charge sensor for highly sensitive detection of DNA sequence.
Biosens Bioelectron
; 20(1): 69-74, 2004 Jul 30.
Article
em En
| MEDLINE
| ID: mdl-15142578
ABSTRACT
We have fabricated an field effect transistor (FET)-type DNA charge sensor based on 0.5 microm standard complementary metal oxide semiconductor (CMOS) technology which can detect the deoxyribonucleic acid (DNA) probe's immobilization and information on hybridization by sensing the variation of drain current due to DNA charge and investigated its electrical characteristics. FET-type charge sensor for detecting DNA sequence is a semiconductor sensor measuring the change of electric charge caused by DNA probe's immobilization on the gate metal, based on the field effect mechanism of MOSFET. It was fabricated in p-channel (P) MOSFET-type because the phosphate groups present in DNA have a negative charge and this charge determines the effective gate potential of PMOSFET. Gold (Au) which has a chemical affinity with thiol was used as the gate metal in order to immobilize DNA. The gate potential is determined by the electric charge which DNA possesses. Variation of the drain current versus time was measured. The drain current increased when thiol DNA and target DNA were injected into the solution, because of the field effect due to the electrical charge of DNA molecules. The experimental validity was verified by the results of mass changes detected using quartz crystal microbalance (QCM) under the same measurement condition. Therefore it is confirmed that DNA sequence can be detected by measuring the variation of the drain current due to the variation of DNA charge and the proposed FET-type DNA charge sensor might be useful in the development for DNA chips.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
DNA
/
Técnicas Biossensoriais
/
Análise de Sequência de DNA
/
Hibridização In Situ
/
Análise de Sequência com Séries de Oligonucleotídeos
/
Técnicas Analíticas Microfluídicas
/
Eletroquímica
Tipo de estudo:
Diagnostic_studies
/
Evaluation_studies
Idioma:
En
Revista:
Biosens Bioelectron
Ano de publicação:
2004
Tipo de documento:
Article