Three-layer quantitative extraction of molecule self-assembly induced surface-stress by cantilever nanomechanical detection

Reported is a novel technique to analyze the surface-stress generated during a SAM (self-assembled molecule-layer) modified on a solid-surface. The individual surface-stress contribution from the three interaction layers, i.e. the surface/head-group interfacial layer, the molecular chain/chain layer and the tail-group/medium layer, can be quantitatively extracted. The quantitative extraction can be implemented by testing the self-assembly induced surface-stress for a group of related SAMs with cantilever sensors. The technique helps to reveal SAM-based nanomechanical sensing mechanism and to optimally design cantilever bio/chemical sensors.