NIR laser induced TPA enhancement of Zn(II)-terpyridine capped gold nanoparticles for targeting mitochondria

Gold nanostructures have recently received increasing interest in bioimaging application. Herein, a novel nanostructure material was designed by the terminal sulfur of the S ((E)-3-(4-([2,2':6',2 ''-terpyridin]-4'-yl)styryl)-9-hexyl-9H-carbazole Zn(SCN)(2) complex) modified with Nano gold. It could be used to target mitochondria under two-photon laser confocal microscopy, due to the energy of laser irradiation gained from the absorbed photons to be dispersed as excess heat to the neighboring particles and thus to induce their fusion, compared with free complex. Furthermore, small size Nano-Au composite was synthesized with longer lifetime, larger two photon absorption cross section (sigma) and third order nonlinear optical susceptibility (chi((3))) in the near-infrared region (NIR), due to the laser irradiation induced charge transfer from complex to the gold nanoparticles, which attracting potential applications in vitro and in vivo cellular imaging. (C) 2016 Published by Elsevier Ltd.