Up-conversion emission and in vitro cytotoxicity characterization of blue emitting, biocompatible SrTiO<sub>3</sub> nanoparticles activated with Tm<sup>3+</sup> and Yb<sup>3+</sup> ions
Blue emitting, up-converting NP's of SrTiO3:Tm3+/Yb3+ synthesized using the citric route are biocompatible towards J774.E whereas the cytotoxic effect to U2OS cells is not particle size dependent but most probably is related to Sr2+ ion release.</p