Vagin MY, Trashin SA, Karyakin AA, Mascini M. Label-free detection of DNA hybridization at a liquid|liquid interface.
Anal Chem 2008;
80:1336-40. [PMID:
18205333 DOI:
10.1021/ac701923c]
[Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A novel electrochemical approach for label-free detection of DNA primary sequence has been proposed. The flow of nonelectroactive ions across a liquid|liquid interface was used as an electrochemical probe for detection of DNA hybridization. Disposable graphite screen-printed electrodes shielded with a thin layer of inert polymer plasticized with water-immiscible polar organic solvent were modified by probe oligonucleotide and used as a DNA sensor. The specific DNA coupling has been detected with impedance spectroscopy by decrease of ion-transfer resistance. The detection limit was of 10-8 M of target oligonucleotide. The reported sensor was suitable for discrimination of a single mismatch oligonucleotide from the full complementary one. The reported DNA sensor was advantageous over known physicochemical approaches, providing the most significant changes in the measured parameters.
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