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Redmond Red as a redox probe for the DNA-mediated detection of abasic sites.

ABSTRACT: Redmond Red, a fluoropore containing a redox-active phenoxazine core, has been explored as a new electrochemical probe for the detection of abasic sites in double-stranded DNA. The electrochemical behavior of Redmond Red-modified DNA at gold surfaces exhibits stable, quasi-reversible voltammetry with a midpoint potential centered around -50 mV versus NHE. Importantly, with Redmond Red positioned opposite an abasic site within the DNA duplex, the electrochemical response is significantly enhanced compared to Redmond Red positioned across from a base. Redmond Red, reporting only if well-stacked in the duplex, represents a sensitive probe to detect abasic sites electrochemically in a DNA-mediated reaction.

SUBMITTER: Buzzeo MC

PROVIDER: S-EPMC2747513 | biostudies-literature | 2008 Nov

REPOSITORIES: biostudies-literature

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Redmond Red as a redox probe for the DNA-mediated detection of abasic sites.

Buzzeo Marisa C MC Barton Jacqueline K JK

Bioconjugate chemistry 20081101 11

Redmond Red, a fluoropore containing a redox-active phenoxazine core, has been explored as a new electrochemical probe for the detection of abasic sites in double-stranded DNA. The electrochemical behavior of Redmond Red-modified DNA at gold surfaces exhibits stable, quasi-reversible voltammetry with a midpoint potential centered around -50 mV versus NHE. Importantly, with Redmond Red positioned opposite an abasic site within the DNA duplex, the electrochemical response is significantly enhanced ...[more]

PMID: 18831574

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