Photoluminescent Hydroxylapatite: Eu3+ Doping Effect on Biological Behaviour

Abstract

Luminescent europium-doped hydroxylapatite (Eu_XHAp) nanomaterials were successfully obtained by co-precipitation method at low temperature. The morphological, structural and optical properties were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), <i>X</i>-ray diffraction (XRD), Fourier Transform Infrared (FT-IR), UV-Vis and photoluminescence (PL) spectroscopy. The cytotoxicity and biocompatibility of Eu_XHAp were also evaluated using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide)) assay, oxidative stress assessment and fluorescent microscopy. The results reveal that the Eu³⁺ has successfully doped the hexagonal lattice of hydroxylapatite. By enhancing the optical features, these Eu_XHAp materials demonstrated superior efficiency to become fluorescent labelling materials for bioimaging applications.