Bovine Serum Albumin Coated Upconversion Nanoparticles for Near Infrared Fluorescence Imaging in Mouse Model.

The unique properties of upconversion nanoparticles (UCNPs) facilitate them to be good candidates for cell and animal imaging. In our work, we developed a facile approach to synthesize nano-composites which is composed of UCNPs and bovine serum albumin (BSA). The nano-composites (UCNPs@BSA) exhibited dual fluorescence in the visible range and NIR range simultaneously. The low cytotoxicity of UCNPs and UCNPs@BSA was demonstrated in L02 and HepG-2 cell lines respectively. The cell imaging investigations verified the biological imaging capability of UCNPs@BSA. Furthermore, UCNPs@BSA displayed favorable in vivo imaging capability in tumor-bearing mice. Consequently, the dual fluorescence emission probe was demonstrated to be a promising candidate for cell and tumor imaging.