报告题目：Nanodevices and smart materials based on DNA i-motif structures
The molecular recognition properties of DNA are sufficiently well understood to enable the self-assembly of defined structures on the nanometer scale. DNA nanostructures have the potential to form the next generation of functional devices. An important challenge is to fabricate molecular components that act as machines. Based on the i-motif structure, a DNA quadruplex which is formed by DNA containing stretches of cytosine under slight acidic conditions, we have demonstrated a pH-change driven DNA nanomotor. Each working cycle of this motor could be finished in seconds and the by-product is H2O plus salt, multiple cycling of this machine has also been demonstrated. We have also shown the working ability of this nanomotor in the solid/liquid interface as well as driving a microcantilever move. In this talk, we will show its application in fabricating smart devices such as pH trigged DNA nanocompartment, enthalpy-driven three-State switching of superhydrophilic/ superhydrophobic surface, as well as photo-pH dually modulated fluorescence switch and controllable assembly of gold nanoparticles.
 N. C. Seeman, Nature 2003, 421, 427-431.