Abstract

When two metallic nanoparticles are located in the vicinity of each other, a frequency for collective oscillation of electrons in a pair of metallic nanoparticles is getting lower than that of a single nanoparticle due to electrostatic attraction of the surface charge [1]. Such a structure, or a metallic nanodimer, has been synthesized by utilizing complementary of DNA. The metallic nanodimer has been employed to observe DNA hybridization [2] and DNA cleavage by an enzyme [3]. In our previous research, DNA conformational change which is caused by a transcription factor was investigated by using the gold nanodimer [4]. The DNA connecting two gold nanoparticles includes a DNA sequence to which a transcription factor (SOX2) binds. We demonstrated that the plasmon resonant wavelength of gold nanodimers coupled with SOX2 was getting longer than that of gold nanodimers without transcription factor. However, a transient kinetics of DNA conformational change caused by the transcription factor has been still unrevealed.

© 2013 Japan Society of Applied Physics, Optical Society of America