Novel NIR-II\n3,5-Julolidinyl aza-BODIPY for Photothermal\nTherapy of Gliomas Stem Cells by Brain Stereotactic Injection

Functional dyes with absorption in the second near-infrared\nwindow\n(NIR-II) show great promise in photothermal therapy. Herein, the novel\nNIR-II 3,5-julolidinyl aza-BODIPY (<b>JLD</b>) was prepared\nand confirmed by X-ray crystallographic analysis for the first time.\nThe molecular packing structure facilitates the <i>J</i>-aggregation packing mode. Self-assembled <b>JLD</b>-nanoparticles\n(<b>JLD</b>-NPs) emit fluorescence (λ<sub>em</sub> = 962\nnm, Φ<sub>f</sub> = 0.1%), and a peak belt covered a NIR-II\nrange of 900–1300 nm. The photothermal conversion efficiency\nwas high and was calculated to be 79%. <b>JLD</b>-NPs with NIR-II\n915 nm laser irradiation had the good tumor-inhibition capability\nwith promoting the apoptosis and inhibiting the stemness of glioblastoma\ncells by brain stereotactic injection and affect the occurrence of\nmalignant events, such as migration and invasion.