Development of core-shell nanoparticles of NaGdF4:Eu3+@Au for X-ray-activated photodynamic therapy (XPDT) applications.

Abstract

Multifunctional nanomaterials are promise for applications in medicine, allowing the combination of treatment and diagnostic capabilities in a single particle, known as theranostics. Photodynamic therapy (PDT) presents great potential for cancer treatment applications but has some limitations, such as low penetration of the wavelengths typically used (ultraviolet and visible light). The procedure known as X-ray photodynamic therapy (XPDT) is based on X-ray absorption and can be used for the treatment of deep-seated tumors. Additionally, the incidence of X-rays in certain materials can result in the emission of light in other regions of the electromagnetic spectrum, such as the visible range, enabling imaging, which is known as X-ray excited optical luminescence (XEOL). NaGdF4:Eu3+ nanoparticles have demonstrated high potential for XPDT and XEOL applications. In this study, we propose the synthesis of multifunctional core-shell nanoparticles of NaGdF4:Eu3+ coated with gold. The goal is not only to improve the biocompatibility and application possibilities of the system but also to investigate the influence of this outer metallic shell on the optical properties of the system. We will focus on understanding the relationship between the gold shell and the luminescence efficiency of the system.