Aggregation-induced emission dye based luminescent silica nanoparticles: facile preparation, biocompatibility evaluation and cell imaging applications

In this work, we reported for the first time that luminescent silica nanoparticles could be easily fabricated by the encapsulation of an aggregation-induced emission dye (named An18) via a modified Stober method. In this method, octadecyltrimethoxysilane (C18-Si) and An18 were first self assembled and served as the core of the silica nanoparticles. Then another silicate precursor, tetraethoxysilane, was further coated on the luminescent core, thus forming luminescent silica nanoparticles. The properties of the thus obtained luminescent silica nanoparticles (named An18-SiO2 NPs) were investigated by fluorescence spectroscopy, transmission electron microscopy and Fourier transform infrared spectroscopy. The biocompatibility and cell uptake behavior of the An18-SiO2 NPs were further investigated to evaluate their potential for biomedical applications. Our results demonstrated that the An18-SiO2 NPs have a uniform spherical morphology (with diameter of 70-80 nm), high water dispersibility, remarkable fluorescent properties and excellent biocompatibility, making them a promising candidate material for various biomedical applications.