Novel Fluorescent Silica Nanoparticles: Towards Ultrabright Silica Nanoparticles

A new class of silica fluorescent nanoparticles (≈30-nm diameter; see image) is described, in which organic fluorescent dyes are physically entrapped inside self-sealed silica nanochannels. The 1D confinement of the dye molecules inside the channels means the dyes can be packed without quenching fluorescence, ≈250 times denser inside the nanoparticles than in aqueous medium. The synthesized particles are compatible with labeling biological cells.