Near-infrared long afterglow nanoparticles with photothermal and photodynamic synergistic therapeutic capabilities for tumor therapy.

Near-infrared long afterglow nanomaterials offer a high-sensitivity and high-signal-to-noise ratio imaging effect due to their ability to penetrate strongly and zero tissue background fluorescence. These features enable them to have excellent application potential in the biological field. This study designs a PDT/PTT synergistic targeted treatment nanoplatform, ZPPZF (ZZGGCB-PANI-PEG-ZnPc-FA), for precise tumour treatment. The long-remaining-illumination material, Zn1.5Zr0.5Ga3.2Ge0.6O8:0.1%Cr,0.2%Bi, is coated with PANI on the surface and further modified with PEG, ZnPc and FA. The residual luminescence of the long-remaining-illumination material is utilized for near-infrared fluorescence imaging and to activate the photosensitizer and PANI to achieve the complementary therapeutic effect of PTT and PDT. The in vivo and in vitro treatment results show that the material can significantly inhibit tumour cells. The inhibition rate of tumour cells reaches 85% two weeks after injection of ZPPZF, and it has satisfactory biological safety with no tissue damage or inflammatory response. At the same time, in vivo near-infrared imaging facilitated monitoring of therapeutic efficacy and informed treatment planning. Overall, ZPPZF nanoparticles provide a new reference scheme for PTT and PDT synergistic treatment.