Smart Phototheranostics based on Carbon Nanohorns for Precise Imaging‐Guided Post‐PDT toward Residual Tumor Cells after Initial Phototherapy

As promising photonic material, phototheranostics can be activated in the laser irradiation range of tumor with sensitivity and spatiotemporal precision. However, it is difficult to completely eradicate solid tumors due to their irregularity and limited laser irradiation area. Herein, multi‐stimulus responsive HA−Ce6@SWNHs were constructed with single‐walled carbon nanohorns (SWNHs) and chlorine e6 (Ce6) modified hyaluronic acid (HA) via non‐covalent binding. This SWNHs‐based phototheranostics not only exhibited water dispersion but also could target tumor and be activated by near‐infrared light for photodynamic therapy (PDT) and photothermal therapy (PTT). Additionally, HA−Ce6@SWNHs could be degraded by hyaluronidase in residual tumor cells, causing HA−Ce6 to fall off the SWNHs surfaces to restore autofluorescence, thus precisely guiding the programmed photodynamic treatments for residual tumor cells after the initial phototherapy. Thus, this work provides a rationally designed multiple‐stimulus‐response strategy to develop smart SWNHs‐based phototheranostics for precise PDT/PTT and post‐treatment imaging‐guided PDT of residual tumor cells. Taking advantage of the multi‐stimulus response to exogenous laser and endogenous hyaluronidase, the HA−Ce6@SWNHs inhibited the growth of residual tumor cells after photodynamic therapy (PDT)/photothermal therapy (PTT) through activatable imaging‐guided PDT. This work provides a rational strategy to develop smart SWNHs‐based phototheranostics for the programmable design of multiple stimulus responses in precision medicine.