Perylene probe induced gold nanoparticle aggregation

Abstract

In the present work, we have studied the aggregation of gold nanoparticles (Au-NPs) induced by a cationic perylene probe (compound 1). The compound 1 free monomer contains a large planar aromatic ring structure that could be efficiently adsorbed onto the surface of the Au-NPs. The strong π–π stacking and hydrophobic interactions among compound 1probe molecules adsorbed on adjacent nanoparticles, and the neutralization of the Au-NP surface citrate ion negative charges induced rapid aggregation of the Au-NPs, and evident UV-vis spectra and solution color changes. The use of this observation for a label-free selective sensing of mercury ion has been demonstrated.