Is GGAG:Ce@SiO$_2$-RB composite a prospective material for X-ray induced photodynamic therapy?

Abstract

Nanocomposite material ($\mathrm{GGAG:Ce^{3+}@SiO_2-RB}$) for potential use in X-ray induced photodynamic therapy (X-PDT) was developed, thoroughly characterized, and evaluated. It consists of a scintillating $\mathrm{Gd_3(Ga_{1-x}Al_x)_5O_{12}:Ce^{3+}}$ core encapsulated in silica layer and functionalized with the photosensitizer Rose Bengal (RB). Radioluminescence measurements confirmed the energy transfer from the scintillating core to Rose Bengal. Dark toxicity and radiosensitisation effects were evaluated using Saccharomyces cerevisiae as a model organism. The nanocomposite showed minimal dark toxicity at concentrations of up to 10 mg/mL. However, X-ray irradiation experiments did not demonstrate significant singlet oxygen production compared to the controls. Although the nanocomposite design shows potential, further optimization is needed to achieve an effective X-PDT performance.