Novel triphenylamine (TPA)-based derivative L, which shows strong affinity for SiO and fluorometric detection of Cu over other anions or cations, has been synthesized by simple steps. The experimental results displayed that derivative L has a remarkable sensitivity towards SiO 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 Cuvia 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 SiO or Cu in live cells by fluorescence confocal microscopy.