Preclinical Studies on the Photothermal Therapy of NIR-II AIEgens: Across Tumor Types

Malignant tumors continue to pose a significant global health challenge, necessitating the development of precise and efficacious therapeutic strategies. Photothermal therapy (PTT), a minimally invasive modality, employs photothermal agents (PTAs) to convert light into localized heat, thereby elevating the local temperature of tumor tissues to induce hyperthermia-mediated cell death. Aggregation-induced emission luminogens (AIEgens) with second near-infrared (NIR-II) emission have garnered increasing attention owing to their high photothermal conversion efficiency, excellent photostability, and capabilities for real-time fluorescence imaging. These properties render NIR-II AIEgens particularly attractive for applications in bioimaging, targeted drug delivery, and integrated theranostics. This review outlines recent advances in the molecular engineering of NIR-II AIEgens aimed at improving photothermal performance and evaluates delivery platforms designed to facilitate tumor-specific accumulation. Preclinical investigations encompassing diverse tumor models-including breast, colorectal, brain, pancreatic, and hepatic malignancies-are systematically assessed with reference to clinically relevant metrics. Finally, the translational potential of NIR-II AIE-based polymeric systems is discussed in the context of future advancements in optical theranostics.