The length effect of probe DNA for hybridization Using DNA self-assembled monolayer

Abstract

To establish a DNA sensor, DNA self-assembled monolayer (SAM) was prepared on a, gold substrate. A probe DNA SAM was fabricated using thiolated DNA composed of single- and double-stranded portions on a gold substrate. The adsorption behaviors of probe DNAs were measured by surface plasmon resonance (SPR). Hybridization efficiency was optimized by controlling the length of spacer inserted in probe portion and SAM layer. Hybridization with target DNA on the DNA array prepared using probe DNA was monitored in situ by SPR. imaging. The SPR image indicates that 10-thymine bases spacer shows the most efficient hybridization on the DNA array. © 2005 The Surface Science Society of Japan.