Controllable self-assembling of gold nanorods via on and off supramolecular noncovalent interactions.

5,15-Bis(4-sulfonatophenyl)porphyrin (DPPS) with a planar conjugated system and two negative charges was found to be able to engender the self-assembling of CTAB-GNRs due to the electrostatic interaction between DPPS and CTAB together with the π-π intermolecular interaction of DPPS, while its bulky supramolecular pseudo[3]rotaxane included by β-cyclodextrin prevented such self-assembling due to the interruption of the above noncovalent interactions.