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Label-free DNA sensor based on surface charge modulated ionic conductance.

ABSTRACT: The surface charge effect in controlling ionic conductance through a nanoporous alumina membrane is investigated for its application in a convenient detection method of unlabeled DNA. To this goal, surface modification with mixtures of neutral silanes and morpholinos (neutral analogues of DNA) was optimized to yield a strong effect on ionic conductance change upon DNA binding, which can exceed an order of magnitude. The effect can be employed in fabrication of inexpensive DNA sensors.

SUBMITTER: Wang X

PROVIDER: S-EPMC2729444 | biostudies-literature | 2009 Apr

REPOSITORIES: biostudies-literature

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Label-free DNA sensor based on surface charge modulated ionic conductance.

Wang Xian X Smirnov Sergei S

ACS nano 20090401 4

The surface charge effect in controlling ionic conductance through a nanoporous alumina membrane is investigated for its application in a convenient detection method of unlabeled DNA. To this goal, surface modification with mixtures of neutral silanes and morpholinos (neutral analogues of DNA) was optimized to yield a strong effect on ionic conductance change upon DNA binding, which can exceed an order of magnitude. The effect can be employed in fabrication of inexpensive DNA sensors. ...[more]

PMID: 19284734

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