Evaluation of the redox properties and anti/pro-oxidant effects of selected flavonoids by means of a DNA-based electrochemical biosensor.
Anal Bioanal Chem
; 376(2): 168-73, 2003 May.
Article
en En
| MEDLINE
| ID: mdl-12712310
ABSTRACT
Quercetin and rutin as well as catechin and epigallocatechin gallate were investigated, as widely distributed representatives of flavonols and flavanols, respectively, regarding their anti/pro-oxidant properties. The flavonoids are irreversibly oxidized at a dsDNA-modified screen-printed electrode within 0.368 to 0.449 V vs. SHE without binding to DNA. Using the DNA biosensor the detection scheme of a DNA prevention/degradation exploits the [Co(phen)(3)](3+) complex as an electrochemical DNA marker. Antioxidant activity of flavonoids was tested in a model cleavage mixture composed of 5 x 10(-7) mol L(-1) [Cu(phen)(2)](2+) as the catalyst, 1 x 10(-3) mol L(-1) ascorbic acid as the chemical reductant and atmospheric oxygen as the natural oxidant where reactive oxygen radicals are generated. The antioxidant activity increases with the concentration of flavonoids reaching a maximum where pro-oxidative behaviour becomes of importance. The pro-oxidant potency of flavonoids depends on the presence of atmospheric oxygen and follows the order quercetin>rutin>epigallocatechin gallate>catechin.
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Banco de datos:
MEDLINE
Asunto principal:
Flavonoides
/
ADN
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Técnicas Biosensibles
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Catequina
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Oxidantes
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Electroquímica
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Antioxidantes
Idioma:
En
Año:
2003
Tipo del documento:
Article