Nanomodulators Capable of Timely Scavenging ROS for Inflammation and Prognosis Control Following Photothermal Tumor Therapy

Abstract Despite the accuracy advantages of photothermal therapy (PTT), heat stress‐initiated free radicals and damage‐activated immune cells form a malignant positive feedback cycle following light irradiation. Herein, a 2D allomelanin nanomodulator with perpendicularly oriented oligomer planes is prepared by the guidance of DNA to achieve timely scavenging of reactive oxygen species (ROS) for inflammation and prognosis control following PTT. A large exposure degree of phenol groups and the effective transfer of delocalized electrons result in ultra‐fast redox reactions that can be boosted by a self‐amplifying process through structure disintegration. Compared with conventional photothermal agents, the nanodisks reduce the accumulation of ROS during PTT by 25‐fold, downregulate the proinflammatory factors, and adjust inflammation levels to baseline. Thereby, successful modulation of M2‐type macrophages in paratumor tissues significantly prevents burn wound progression and accelerates tissue repair, while well‐controlled neutrophil extracellular traps and largely recruited CD4 + /CD8 + T cells (1.6–3.2‐fold) in the ablation site suppress the relapse of distant tumors. The study provides a useful inspiration on rationally modulating redox active nanostructures to address prognosis issues following PTT.