AFM - TIRFM system

Recently, we applied AFM to investigate the biological system due to its ability in high resolution imaging and force measurement in liquid. For example, the observation of the helix filament structure of ScDmc1-ssDNA has been demonstrated by using CNT-AFM tip. We also combine AFM with optical microscopy that provides additional detection channel. For example, we have detected the dynamics of 17-mer DNA triplex dissociation mechanism at the molecular level. The maximum rupture force of DNA triplex was found at pH 4.65, consistent with our previous study.

  1. Ming-Hui Lee, Yuan-Chih Chang, Eurie L. Hong, Jennifer Grubb, Chia-Seng Chang, Douglas K. Bishop, and Ting-Fang Wang ”Calcium Ion Promotes Yeast Dmc1 Activity via Formation of Long and Fine Helical Filaments with Single-stranded DNＡ”THE JOURNAL OF BIOLOGICAL CHEMISTRY VOL. 280, NO. 49, pp. 40980–40984, December 9, 2005
  2. Chia-Ching Chang, Po-Yen Lin, Yen-Fu Chen, Chia-Seng Chang, and Lou-Sing Kan, Direct visualization of triplex DNA molecular dynamics by fluorescence resonance energy transfer and atomic force microscopy measurements, Appl. Phys. Lett. 91, 203901 (2007).