Fluorescent silica nanoparticles.

We report on the preparation of fluorescent silica nanoparticles (NPs). They have been prepared by (a) modification of the NPs by amino groups and subsequent introduction of amino-reactive fluorophores of various color and (b) by modification of the NPs by either azido groups or alkyne groups and subsequent conjugation to fluorophores by so-called click chemistry, which is a novel approach toward modifying silica NPs. The new NPs were characterized in terms of size and spectral properties.