Synthesis of Water-Soluble Iridium (III)-Containing Nanoparticles for Biological Applications

Abstract

Water-soluble nanoparticles (Ir/PGlc-NP, Ir/β-1,3-glucan-NP) based on water-soluble glycopolymers (PGlc),β-1,3-glucan polysaccharide, and conjugated phosphorescent Ir (III) complexes were successfully synthesized by self-assembly. The obtained nanoparticles have good spherical morphological characterization with a mean diameter of 50 nm measured by TEM. Ir/PGlc-NP and Ir/β-1,3-glucan-NP showed the same emission maxima at 565 nm in aqueous solution and both caused effective apoptosis and death of HepG2 and Hela cells after being irradiated at 445 nm for 30 min in vitro. Fluorescence cellular imaging was conducted by confocal laser scanning microscopy (CLSM) using HepG2 cells as the model cell in which the nanoparticles had successfully entered into the cytoplasm with high brightness. Furthermore, after injecting the nanoparticles into live mice in vivo, the real-time fluorescence imaging as well as the nanoparticles distribution in organs at 24 hours after administration indicated that these nanoparticles can serve as fluorescent imaging contrast for further biological applications.

Shining New Light on Biological Systems: Luminescent Transition Metal Complexes for Bioimaging and Biosensing Applications

“…339 Sun, Huang, and co-workers have developed water-soluble glyconanoparticles by self-assembling a luminescent iridium-(III) complex (167) (Chart 76) with a water-soluble glycopolymer (poly(glucose)) or polysaccharide (β-1,3-glucan). 340 These glyconanoparticles are efficiently internalized into live HepG2 cells and distributed throughout the whole cytoplasm. In vivo biodistribution studies in live mice reveal significant accumulation of the NPs in the liver, indicating their potential as luminescent probes for tissue imaging.…”

“…Sun, Huang, and co-workers have developed water-soluble glyconanoparticles by self-assembling a luminescent iridium(III) complex ( 167 ) (Chart ) with a water-soluble glycopolymer (poly(glucose)) or polysaccharide (β-1,3-glucan) . These glyconanoparticles are efficiently internalized into live HepG2 cells and distributed throughout the whole cytoplasm.…”

pH-Responsive Emission of Novel Water-Soluble Polymeric Iridium(III) Complexes

“…To this end, the ligands may be functionalized with hydrophilic groups [ 13 , 14 , 32 , 33 , 34 , 35 , 36 , 37 ] or the counter ions of cationic cyclometalated Ir(III) complexes may be adequately chosen to sustain water-solubility [ 14 , 38 , 39 , 40 ]. Alternatively, the covalent attachment of Ir(III) complexes onto a polymeric chain, using water-soluble polymers such as poly(N-isopropylacrylamide), poly(N-vinylpyrrolidone), and polyethyleneglycols, has been also applied [ 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 ].…”