Anodized aluminum oxide-based capacitance sensors for the direct detection of DNA hybridization.
We fabricated a capacitance sensor based on an anodized aluminum oxide (AAO) nanoporous structure to detect DNA hybridization. We utilized Au film deposited on the surface of the AAO membrane and Au nanowires infiltrating the nanopores as the top and bottom electrodes, respectively. When completely complementary target DNA molecules were added to the sensor-immobilized DNA molecule probes, the capacitance was reduced; with a concentration of 1pM, the capacitance decreased by approximately 10%. We measured the capacitance change for different concentrations of the target DNA solution. A linear relationship was found between the capacitance change and DNA concentration on a semi-logarithmic scale. We also investigated the possibility of detecting DNA molecules with a single-base mismatch to the probe DNA molecule. In contrast to complementary target DNA molecules, the addition of one-base mismatch DNA molecules caused no significant change in capacitance, demonstrating that DNA hybridization was detected with single nucleotide polymorphism sensitivity.
Kang
Bongkeun
B
Department of Physics and National Core Research Center for Nanomedical Technology, Yonsei University, 134 Shinchon-dong, Seodaemun-gu, Seoul 120-749, Republic of Korea.
Yeo
Unjin
U
Yoo
Kyung-Hwa
KH
D000537:Aluminum Oxide / Q000737:chemistry*; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D017076:Computer-Aided Design; D003217:Conductometry / Q000295:instrumentation* / Q000379:methods; D025802:Electric Capacitance; D004566:Electrodes; D004867:Equipment Design; D019544:Equipment Failure Analysis; D017403:In Situ Hybridization / Q000295:instrumentation*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D000537:Aluminum Oxide