Rare earth fluorescent nanoparticles for specific cancer cell targeting

Terbium layered hydroxide nanoparticles (Tb2(OH)5NO3) were synthesized by a one-pot coprecipitation method. The characterization of this preparation revealed highly oriented fluorescent nanoparticles. An attempt to improve the properties of Tb2(OH)5NO3 resulted in the preparation of two optimized nanoparticles. In particular, Tb2(OH)5NO3:Eu and Tb2(OH)5NO3-FA were prepared when Tb2(OH)5NO3 was doped with Europium and when the surface was modified with folic acid (FA), respectively. The size of the above nanoparticles was below 100 nm, and thus they have the potential to be used for biomedical applications. The interaction of nanoparticles with human cells was studied using confocal microscopy. This study revealed that only the nanoparticles modified with folic acid have the ability to be targeted to HeLa cells. This specific identification of cancer cells, in combination with the fluorescent properties of Tb2(OH)5NO3, could render these nanoparticles appropriate for biomedical applications.