Synthesis and Characterization of Fluorescent Silica Nanoparticles Functionalized with Collagens of Variable Lengths

Collagen, the most abundant protein in human body, has been widely used as an excellent natural material for diverse biomedical applications due to its superior properties such as ample biological interaction sites, minimal immunogenicity and high biocompatibility. Collagens of different lengths are produced by recombinant technology and utilized to functionalize fluorescent silica nanoparticles (FNPs). The collagen-functionalized FNPs display mono-disperse distribution, but their sizes are dependent on the length of collagen. These modified FNPs all show nice fluorescence profile as well as low cytotoxicity, suggesting promising applications in bioimaging. We have demonstrated that various types of collagen, conveniently produced by recombinant technology, can be used to modify silica nanoparticles with nice characteristics such as mono-dispersion, non-interference in fluorescence and low toxicity. It may endow fluorescent silica nanoparticles with broad biological applications.