Preparation of novel silica nanoparticles with controllable fluorescence intensity from porphyrin-bridged silsesquioxane

A method for the fabrication of an improved class of controllable fluorescence intensity, highly sensitive and photostable porphyrin doped silica nanoparticles (PDSNPs) was demonstrated. The fluorescence intensity of PDSNPs could be controlled by finely tuning self-dissociated time of the precursor of porphyrin-bridged silsesquioxane. Porphyrin was well dispersed into the silica matrix due to the covalent attachment in the system, thus entirely avoiding the porphyrin leakage and fluorescence quenching effects. The resultant PDSNPs with a narrow size-distributed region and a regular spherical structure can be attained.