One-pot synthesis of monodispersed silica nanoparticles for diarylethene-based reversible fluorescence photoswitching in living cellsElectronic supplementary information (ESI) available: Synthetic schemes, detailed experimental section, mass/UV-Vis/fluorescence spectra, cytotoxicity assay results, flow cytometry histograms, etc. See DOI: 10.1039/c3cc42852d

A small 29 nm monodispersed silica nanoparticle 1a was synthesized as a diarylethene-based reversible fluorescence photoswitch by copolymerizing silane precursors in one-pot including 3a and 4 . Reversible photoswitching of nanoparticle 1a was successfully achieved in living cells to show its potential as a highly distinguishable and safe fluorescence probe for cell tracking. A small 29 nm monodispersed silica nanoparticle was synthesized by one-pot multicomponent copolymerization for reversible fluorescence photoswitching in living cells.