Nano Archive

DNA sensing by silicon nanowire: Charge layer distance dependence

Zhang, Guo-Jun and Zhang, Gang and Chua, Jay Huiyi and Chee, Ru-Ern and Wong, Ee Hua and Agarwal, Ajay and Buddharaju, Kavitha D. and Singh, Navab and Gao, Zhiqiang and Balasubramanian, N (2008) DNA sensing by silicon nanowire: Charge layer distance dependence. NANO LETTERS, 8 (4). pp. 1066-1070.

Full text is not hosted in this archive but may be available via the Official URL, or by requesting a copy from the corresponding author.

Official URL:


To provide a comprehensive understanding of the field effect in silicon nanowire (SiNW) sensors, we take a systematic approach to fine tune the distance of a charge layer by controlling the hybridization sites of DNA to the SiNW preimmobilized with peptide nucleic acid (PNA) capture probes. Six target DNAs of the same length, but differentiated successively by three bases in the complementary segment, are hybridized to the PNA. Fluorescent images show that the hybridization occurs exclusively on the SiNW surface between the target DNAs and the PNA. However, the field-effect response of the SiNW sensor decreases as the DNA (charge layer) moves away from the SiNW surface. Theoretical analysis shows that the field effect of the SiNW sensor relies primarily on the location of the charge layer. A maximum of 102% change in resistance is estimated based on the shortest distance of the DNA charge layer (4.7 angstrom) to the SiNW surface.

Item Type:Article
Subjects:Material Science > Functional and hybrid materials
Analytical Science > Nanotechnology for sensing and actuating
Material Science > Nanostructured materials
ID Code:1242
Deposited By:Anuj Seth
Deposited On:15 Dec 2008 16:51
Last Modified:12 Feb 2009 14:11

Repository Staff Only: item control page