Cytotoxicity and cellular uptake of red-emitting organic-inorganic hybrid nanoparticles

Highly luminescent and stable hybrids composite Eu(TTA-TESP)(3)(P(Oct)(3))@mSiO(2) [europium (III); 4,4,4-tri- fluoro-1-(thiophen-2-yl)-2-(3-(triethoxysilyl)propyl) butane-1,3-dione = TTA-TESP; trioctylphosphine = (P (Oct)3); mesoporous silica = mSiO(2)]; were prepared. Eu(III) and P(Oct)3 molecules reacted to TTA-TESP grafted mSiO(2) through strong covalent bonding inside the cavity/mesopores of mSiO2. Photoluminescence (PL) curves of emission spectra and excitation spectrum depending on different concentrations show typical characteristic with a maximum emission peaks at 621 nm which is related to D-5(0)-> F-7(2) transition of Eu(III) complexes with strong red emission. The cytotoxic effects depending on concentrations and incubation times of Eu(TTA-TESP)(3)(P (Oct)3)3@mSiO(2) were confirmed to be practically non-toxic in terms of cytotoxicity in HepG2 cells. From the in- vivo results, Eu(TTA-TESP)(3)(P(Oct)(3))(3) @mSiO(2 )particles mainly accumulated in the liver, and the fluorescence signal in the heart, spleen, kidney, lung, and pancreas was weak. The result suggests that the synthesized Eu (TTA-TESP)3(P(Oct)3)(3)@mSiO(2) particles can be used as a imaging agent for the liver through intravascular injection.

Automated summary

In this study, highly luminescent and stable hybrid composite Eu(TTA-TESP)(3)(P(Oct)(3))@mSiO(2) was successfully prepared, and its low cytotoxicity and potential as a liver imaging agent were confirmed through cell and in vivo experiments.