Intraperitoneal subcutaneous injection has been highly envisioned as an effective yet low-risk method for delivering photothermal agents for superficial tumor photothermal therapy. However, due to blockage by the complex subcutaneous tissue, delivering injected photothermal agents to specific tumors remains a key challenge. Here, this study reports a polydopamine (PDA)-coated spherical core/shell nanomotor, with fluorescent indocyanine green (ICG) anchored on its PDA shell.Upon the first near-infrared (NIR-I) irradiation, the motor can generate favorable photothermal effects, while emitting strong ICG fluorescence in the second near-infrared window (NIR-II). The heat converts the motor into an active photothermal agent capable of thermophoretic propulsion along the irradiation direction in subcutaneous tissue, while the ICG fluorescence can guide the motor’s subcutaneous movement to specific tumors through real-time NIR-II imaging. These features enable the motor to move to the tumor after peritumoral injection, thereby achieving enhanced photothermal therapy (PTT). The results demonstrated here suggest that an integrated nanorobotic tool for superficial PTT using peritumoral administration highlights NIR-II imaging-guided subcutaneous propulsion.

In the treatment of superficial tumors, photothermal therapy has attracted significant attention due to its non-invasive nature and low toxicity. However, the key challenge in clinical translation has been how to deliver photothermal agents precisely and efficiently to deep tumor sites, particularly in overcoming the barriers posed by complex subcutaneous tissues. Recently, an innovative study proposed a thermal-swimming nanomotor system guided by second near-infrared (NIR-II) imaging, offering a new intelligent solution for precise photothermal treatment of superficial tumors.

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DOI: 10.1002/adma.202417440