Aggregation-enhanced emission in gold nanoparticles protected by tetradentate perylene derivative.

Three novel gold nanoparticle (AuNPs) composites protected by perylene bisimide derivatives have been designed and synthesized. Thanks to the rational molecular design, AuNPs capped by N,N'-2,6-bis(4-aminomethylpyridine)-1,6,7,13-tert-[4-(hydroxymethyl)phenoxy-5-(1,2-dithiolan-3-yl)pentanoate]-3,4,9,10- tetracarboxylic acid bisimide (8SP-AuNPs) exhibited unusual enhancement in fluorescence intensity, while the other two nanoparticle composites showed slight enhancement or quench in emission spectra. The structural effect of ligands on aggregation enhanced emission had been studied, and temperature dependence experiments had been conducted. Deductive explanation had been made to elucidate the special spectral behavior of 8SP-AuNPs led by restricted motion of perylene chromophores in the packed nanoclusters.