MECHANICALLY STRETCHING FOLDED NANO-PI-STACKS REVEALS PICO-NEWTON ATTRACTIVE FORCES

Abstract

Picoforce atomic force microscopy (AFM) and specific DNA hybridization have been used to lock onto synthetic nano-pi-stacks, revealing the secrets of thermophilic, albeit weak, pi-pi interactions. A cone-shaped dendron created an appropriate lateral spacing to ensure that most times a single stack was confined between the tip and the substrate, eliminating undesired multi-molecular pulling and greatly simplifying data analysis.