Pluronic^®F127 micelles template biomimetic assembly and optical properties of red fluorescent silica nanocapsules

Fluorescent dye-doped silica nanoparticles (FDSNPs) have exhibited great potential in applications including solid-state lighting, chemical sensing, and biological theranostics. However, the wide application of FDSNPs is still a big challenge due to the lack of efficient synthesis strategy. Herein, red fluorescent hybrid silica nanocapsules (FHSNCPs) were assembled by a green, convenient, and benign method based on Pluronic^®F127 micelles as a soft template. Morphologies, structures, sizes, and fluorescence properties of the as-prepared silica nanocapsules were characterized by transmission electron microscopy (TEM), dynamic light scattering (DLS), Fourier Transform Infrared Spectroscopy (FTIR) and fluorescence spectroscopy. The size of the silica nanocapsules was well controlled from 20.5 nm to 23.6 nm by varying the concentration of F127 and tetramethylorthosilicate (TMOS). Further investigations reveal that these nanocapsules exhibit monodisperse size, stable aqueous dispersibility, and novel optical properties, which show great potential for fluorescence imaging and temperature monitoring in biological tissues.