Breast cancer reported in the young women exhibits high local and distant recurrence and a poor prognosis. Rare earth doped calcium phosphate phosphors have been extensively investigated due to their unique applications in biomedicine.

In the current study, Tb³⁺, Ce³⁺ doped Ca₃(PO₄)₂ phosphor were prepared by hydrothermal method at 150°C using citric acid as additive and characterized by PXRD, FT-IR, TG-DTA, EDX, TEM and PL techniques. The photoluminescence properties of Tb³⁺, Ce³⁺ doped Ca₃(PO₄)₂ phosphor was investigated upon photo excitation at 240 nm. Antiproliferative activity was evaluated by MTT, BrdU proliferation, ELISA, Methylene blue and caspase-3 assays.

Ca₃(PO₄)₂:Tb³⁺, Ce³⁺ phosphor exhibited needle like morphology with length and width ∼100-500 nm and ∼40-50 nm, respectively. It exhibited green emission at 550 nm corresponding to ⁵D₄→⁷F₅ transition with the CIE coordinates (x, y) as (0.284, 0.614). It also showed remarkable concentration dependent cytotoxicity against MCF-7 as well as MDA-MB 231 cells with negligible cytotoxicity compared to MCF-12A, a human epithelial healthy cell line. It reduced the proliferative index of both cell lines in a concentration dependent manner by inhibiting DNA synthesis and Ki67 protein. It also induced distinct apoptotic changes in the morphology of cell and nucleus and also activated the caspase-3 activity in breast cancer cell lines.

The results suggest that Ca₃(PO₄)₂:Tb³⁺, Ce³⁺ phosphor may be useful for therapeutic application in clinical settings.