A unique bifunctional probe for detecting silicate anions and cupric cations: the modified silica nanoparticles and their coordination

Abstract

Novel triphenylamine (TPA)-based derivative L, which shows strong affinity for SiO₃²⁻ and fluorometric detection of Cu²⁺ over other anions or cations, has been synthesized by simple steps. The experimental results displayed that derivative L has a remarkable sensitivity towards SiO₃²⁻ by producing separately dispersed and modified silica nanoparticles (NPs) with an average size of 377 nm in acetonitrile solution. Moreover, L also displayed obvious selectivity to Cu²⁺via 29-fold fluorescence intensity enhancement with a blue shift of 33 nm due to the formation of a 2 : 1 complex at room temperature. In addition, the probe could map the distribution of intracellular SiO₃²⁻ or Cu²⁺ in live cells by fluorescence confocal microscopy.