Introducing Specific Iodine Ions in Perovskite‐Based Nanocomplex to Cater for Versatile Biomedical Imaging and Tumor Radiotherapy

Multimodal biomedical imaging and imaging-guided therapy have garnered extensive attention owing to the aid of nanoagents with the aim of further improving the therapeutic efficacy of diseases. The ability to engineer nanocomplexes (NCs) or control how they behave within an organism remains largely elusive. Here, a multifunctional nanoplatform is developed based on stabilized I-doped perovskite, CsPbBr_{3 -x} I_x @SiO₂ @Lip-c(RGD)₂ (PSL-c(RGD)₂ ) NCs. In particular, by regulating the amount of regular I^- ions introduced, the fluorescence emission spectrum of perovskite-based NCs can be modulated well to match the requirement for biomedical optical imaging at the scale from molecule, cell to mouse; doping ¹²⁵ I enables the nanoformulation to be competent for single-photon emission computed tomography (SPECT) imaging; the introduction of ¹³¹ I^- imparts the NCs with the capability for radiotherapy. Through facile manipulation of specific iodine ions, this nanoplatform exhibits a remarkable ability to match multifunctional biomedical imaging and tumor therapy. In addition, their in vivo behavior can be manipulated by adjusting the thickness of the silica shell and the surface polarity for more practical applications. These experimental explorations offer a novel approach for engineering desirable multimodal NCs to simultaneously image and combat malignant tumors.