CT/MRI‐Guided Synergistic Radiotherapy and X‐ray Inducible Photodynamic Therapy Using Tb‐Doped Gd‐W‐Nanoscintillators

The use of X‐rays instead of UV/Vis light to trigger photodynamic therapy, named X‐ray inducible photodynamic therapy, holds tremendous promise due to a high penetration capacity in tissues and is worthy of in‐depth study. In this study, a novel multifunctional nanoagent based on Merocyanine 540‐coupled Gd 2 (WO 4 ) 3 :Tb nanoscintillators and the vitalization of its abilities for dual‐modal computed tomography and the magnetic‐resonance‐imaging‐guided synergistic radio‐/X‐ray inducible photodynamic therapy of tumors is reported. Synergistic therapies show a higher tumor growth inhibition efficiency at a lower X‐ray dose than radiotherapy alone. Through this proof‐of‐concept work, a way to tactfully understand and utilize nanoscintillators for cancer theranostics is shown.