Rare earth doped nanoparticles of oxides for biomarkers applications

First generation of biomarkers (fluorescence labels) is based on organic dyes. To replace them nanoparticles (NPs)/quantum dots (QDs) of highly fluorescent CdTe-, CdS- and CdSe-based biomarkers were introduced. Despite the fact that these NPs show some advantageous properties, their use is limited by blinking, spectral diffusion of emission and use of cadmium, which should be avoided in the case of biological and medical applications. This fact motivated us to develop new generation of biomarkers using biocompatible oxides - ZnO, ZnAl₂O₄ and ZrO₂. Their emission is activated by doping with rare earth (RE) ions.