Sensors 2013, 13(2), 2267-2278; doi:10.3390/s130202267
Article

Label-Free Potentiometry for Detecting DNA Hybridization Using Peptide Nucleic Acid and DNA Probes

1 Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, 2-3-10 Kanda-Surugadai, Chiyoda, Tokyo 101-0062, Japan 2 National Institute of Advanced Industrial Science and Technology (AIST), 16-1 Onogawa, Tsukuba, Ibaraki 305-8569, Japan
* Authors to whom correspondence should be addressed.
Received: 25 October 2012; in revised form: 15 January 2013 / Accepted: 4 February 2013 / Published: 7 February 2013
(This article belongs to the Special Issue State-of-the-Art Sensors Technology in Japan 2012)
PDF Full-text Download PDF Full-Text [479 KB, uploaded 7 February 2013 14:25 CET]
Abstract: Peptide nucleic acid (PNA) has outstanding affinity over DNA for complementary nucleic acid sequences by forming a PNA-DNA heterodimer upon hybridization via Watson-Crick base-pairing. To verify whether PNA probes on an electrode surface enhance sensitivity for potentiometric DNA detection or not, we conducted a comparative study on the hybridization of PNA and DNA probes on the surface of a 10-channel gold electrodes microarray. Changes in the charge density as a result of hybridization at the solution/electrode interface on the self-assembled monolayer (SAM)-formed microelectrodes were directly transformed into potentiometric signals using a high input impedance electrometer. The charge readout allows label-free, reagent-less, and multi-parallel detection of target oligonucleotides without any optical assistance. The differences in the probe lengths between 15- to 22-mer dramatically influenced on the sensitivity of the PNA and DNA sensors. Molecular type of the capturing probe did not affect the degree of potential shift. Theoretical model for charged rod-like duplex using the Gouy-Chapman equation indicates the dominant effect of electrostatic attractive forces between anionic DNA and underlying electrode at the electrolyte/electrode interface in the potentiometry.
Keywords: PNA; DNA; hybridization; electrostatic energy; label-free biosensor; potentiometry

Article Statistics

Load and display the download statistics.

Citations to this Article

Cite This Article

MDPI and ACS Style

Goda, T.; Singi, A.B.; Maeda, Y.; Matsumoto, A.; Torimura, M.; Aoki, H.; Miyahara, Y. Label-Free Potentiometry for Detecting DNA Hybridization Using Peptide Nucleic Acid and DNA Probes. Sensors 2013, 13, 2267-2278.

AMA Style

Goda T, Singi AB, Maeda Y, Matsumoto A, Torimura M, Aoki H, Miyahara Y. Label-Free Potentiometry for Detecting DNA Hybridization Using Peptide Nucleic Acid and DNA Probes. Sensors. 2013; 13(2):2267-2278.

Chicago/Turabian Style

Goda, Tatsuro; Singi, Ankit B.; Maeda, Yasuhiro; Matsumoto, Akira; Torimura, Masaki; Aoki, Hiroshi; Miyahara, Yuji. 2013. "Label-Free Potentiometry for Detecting DNA Hybridization Using Peptide Nucleic Acid and DNA Probes." Sensors 13, no. 2: 2267-2278.

Sensors EISSN 1424-8220 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert