Effect of <em>γ</em>-radiation on structure, photoluminescence properties and <em>in vitro</em> cytotoxicity of LaPO₄:Tb³⁺,Ce³⁺ phosphor

Abstract

Lauric acid capped Ce³⁺ sensitized LaPO₄:Tb³⁺ nanorods have been synthesized by hydrothermal route at 150 °C. The structure, stability and luminescent properties have been examined by TEM, TG/DTA, FT-IR, powder X-ray diffraction and PL spectral data. Cytotoxic activity has been examined by MTT assay. The LaPO₄:Tb³⁺,Ce³⁺ phosphor exhibits four emission peaks at 485, 551, 583 and 619 nm corresponding to ⁵<em>D</em>₄→⁷<em>F</em>₆, ⁵<em>D</em>₄→⁷<em>F</em>_5, ⁵<em>D</em>₄→⁷<em>F</em>₄ and ⁵<em>D</em>₄→⁷<em>F</em>₃ transitions, respectively. The influence of γ-radiation on photoluminescence properties of LaPO₄:Tb³⁺,Ce³⁺ phosphor has also been examined at 5 and 300 kGy. Furthermore, LaPO₄ and LaPO₄:Tb³⁺,Ce³⁺ phosphors exhibit 80–82% cytotoxic effect against breast cancer cell lines, MDA-MB 231 and MCF-7. The IC₅₀ values for LaPO₄ and LaPO₄:Tb³⁺,Ce³⁺ phosphors are 17.2 and 13.5 µg/mL against MCF-7 and 21.5 and 15.0 µg/mL against MDA-MB 231 cell line, respectively.