Highly fluorescent sub 40-nm aminated mesoporous silica nanoparticles

We report the room temperature synthesis of highly fluorescent, sub-40 nm aminated mesoporous silica nanoparticles in water using triethanolamine (TEA) as catalyst. Co-condensation reactions between silica precursors, i.e., tetraethoxysilane and 3-aminopropyl triethoxysilane, allows the incorporation of amino moieties and conjugated fluorescent dye (tetramethylrhodamine-5(6)-isothiocyanate; TRITC) throughout the silica matrix. Resulting materials are characterized using a combination of transmission electron microscopy, nitrogen sorption measurements, dynamic light scattering, zeta potential measurements, thermogravimetric analysis, fluorescence correlation spectroscopy and solid-state 29Si-NMR spectroscopy. The TEA-catalyzed system leads to the formation of bright and discrete sub-40 nm aminated mesoporous silica nanoparticles with disordered pore structure and high organic content. Resulting nanomaterials may find use as simultaneous fluorescent probes and drug delivery vehicles in future theranostic applications.