Background: Fluorescence based bioimaging is one of the widely used method
for obtaining imperative information on life processes.
Objective: Within the expansive spectrum of fluorescent agents being investigated, the trivalent
Lanthanide (Ln) ion based nanoparticles have attracted attention due to their intrinsic
Methods: Here we report a modified sol gel assisted synthesis of Europium (Eu) and Samarium
(Sm) doped Hydroxyapatite nanoparticles (HAp NPs). Doping Ln ions in the selffluorescent
hydroxyapatite lattice contributed towards an increased luminescence in the
Results: The XRD patterns reveal that the Eu+3 and Sm+3 doped HAp NPs display the
characteristic peaks of hydroxyapatite in a hexagonal lattice structure, and the FTIR data
confirms presence of characteristic functional groups. The as-synthesized HAp NPs exhibit
short rod-shaped morphology with average length less than 60 nm. Upon excitation at representative
wavelengths, the doped HAp NPs demonstrated characteristic emission lines of
Eu+3 and Sm+3.
Conclusion: The as-synthesized NPs displayed no toxicity towards HeLa cells and are
easily internalized, exhibiting their potential as promising live cell bioimaging agents.