Hostname: page-component-78c5997874-mlc7c Total loading time: 0 Render date: 2024-11-19T06:31:38.191Z Has data issue: false hasContentIssue false

Nanogap Capacitors for Label Free DNA Analysis

Published online by Cambridge University Press:  01 February 2011

Joon Sung Lee
Affiliation:
Berkeley Sensor and Actuator Center Department of Bioengineering, University of California at Berkeley, Berkeley, CA 94720
Yang-Kyu Choi
Affiliation:
Berkeley Sensor and Actuator Center Department of Bioengineering, University of California at Berkeley, Berkeley, CA 94720
Michael Pio
Affiliation:
Berkeley Sensor and Actuator Center Department of Bioengineering, University of California at Berkeley, Berkeley, CA 94720
Jeonggi Seo
Affiliation:
Berkeley Sensor and Actuator Center Department of Bioengineering, University of California at Berkeley, Berkeley, CA 94720
Luke P. Lee
Affiliation:
Berkeley Sensor and Actuator Center Department of Bioengineering, University of California at Berkeley, Berkeley, CA 94720
Get access

Abstract

Nanogap capacitors are fabricated for DNA hybridization detection. Without labeling, the nanogap capacitors on a chip can function as DNA microarray sensors. The difference in dielectric properties between single-stranded DNA and double-stranded DNA permits use of capacitance measurements to detect hybridization. To obtain high detection sensitivity, a 50 nm gap capacitor was fabricated using a Si-nanotechnology. To ensure proper measurement of DNA's dielectrical properties, the probe ssDNA was first immobilized onto the electrode surface using self-assembly monolayers and allowed to hybridize with the target ssDNA. The capacitance changes were measured for 35-mer homonucleotides. The self-assembly monolayer and DNA immobilization events were verified independently by contact angle measurement and FTIR. Capacitance values are measured at frequencies ranging from 75 kHz to 5 MHz, using 0 VDC bias and 25 mVAC signals. Approximately 9% change in capacitance was observed after DNA hybridization at 75 kHz.

Type
Research Article
Copyright
Copyright © Materials Research Society 2002

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

[1] Marrazza, G., Chianella, I., Mascini, M., Biosensors and Bioelectronics 14, 43 (1999)Google Scholar
[2] Palecek, E., Fojta, M., Tomschik, M., Wang, J., Biosensors and Bioelectronics 13, 621 (1998)Google Scholar
[3] Piunno, P.A.E., Krull, U.J., Hudson, R.H.E., Damah, M.J., Cohen, H., Analytica Chimica Acta 288, 205 (1994)Google Scholar
[4] Berney, H., West, J., Haefele, E., Alderman, J., Lane, W. and Collins, J.K., Sensors and Actuators B 68, 100 (2000)Google Scholar
[5] Berggren, C., Stalhandske, P., Brundell, J. and Johansson, G., Electroanalysis 11, 156 (1999)Google Scholar
[6] Choi, Y.-K., King, T.-J., and Hu, C., IEEE Trans. Electron Devices 49, 436 (2002)Google Scholar
[7] Hu, J., Wang, M., Weier, H., Frantz, P., Kolbe, W., Ogletree, D. and Salmeron, M., Langmuir 12, 1697 (1996)Google Scholar
[8] Sun, X., He, P., Liu, S., Ye, J. and Fang, Y., Talanta 47, 487 (1998)Google Scholar
[9] Rastogi, V.K., Singh, Chattar, Jain, Vaibhav and Palafox, M. Alcolea, J. Raman Spectrosc. 31 1005 (2000)Google Scholar
[10] Zhang, Shuliang L., Michaelian, Kirk H., and Loppnow, Glen R., J. Phys. Chem. A 102, 461 (1998)Google Scholar