Synthesis and Characterization of Fluorescent, Radio‐Opaque, and Paramagnetic Silica Nanoparticles for Multimodal Bioimaging Applications

Abstract

Fluorescent, radio-opaque, and paramagnetic silica nanoparticles 100 ± 10 nm in size are developed by incorporating fluorescent tris(2,2′-bipyridyl) dichlororuthenium(II) hexahydrate and paramagnetic gadolinium ions. The nanoparticles are radio-opaque due to the presence of electron-dense Ru and Gd atoms. It is estimated that each nanoparticle carries about 16 000 Gd3+ ions. The multimodality of the silica nanoparticles is shown by fluorescence (Figure, left) and X-ray (right) imaging.