Induced photodynamic therapy using nanoparticle scintillators as transducers

A method for photodynamic therapy in a subject, comprising:

• administering to the subject a photodynamic therapeutic system comprising a strontium aluminum oxide nanoparticle of formula SraAlbOc, where a, b and c are integers from 1 to 30, doped with Eu2+, Dy3+, Nd3+, or combinations thereof that emits electromagnetic radiation having a first wavelength when irradiated with electromagnetic radiation having a second wavelength and wherein nanoparticle is from 5 nm to 5000 nm, a photosensitizer which absorbs light of the first wavelength, and a first shell comprising a biocompatible mesoporous silica that forms a coating on the surface of the nanoparticle, a second shell comprising a solid layer of silica wherein the second shell is between the first shell and the surface of the nanoparticle or the second shell surrounds the first shell, wherein the photosensitizer is embedded in the mesoporous silica;
• and
• irradiating the system, thereby causing the nanoparticles to emit electromagnetic radiation having the first wavelength and the photosensitizer to absorb the electromagnetic radiation having the first wavelength.