Solanum lyratum-derived metal-free bio-nanozyme for photothermally self-enhanced cascade catalytic synergistic tumor therapy

Developing multifunctional nanoplatforms for synergistic tumor therapy remains a significant challenge. Here, we report a metal-free bio-nanozyme (SL-BN) derived from the natural medicinal plant Solanum lyratum (SL) via a facile two-step solvothermal and carbonization method. The as-prepared SL-BN integrates triple-enzyme-like (peroxidase, oxidase, and catalase) activities with robust photothermal conversion capabilities across both near-infrared (NIR)-I and -II bio-windows. Within the tumor microenvironment, SL-BN initiates a cascaded catalytic reaction: its catalase-like activity decomposes endogenous H 2 O 2 to self-supply O 2 , thereby relieving hypoxia. This oxygen replenishment, in turn, fuels the oxidase-like activities to generate cytotoxic reactive oxygen species (ROS), creating a positive feedback loop for enzyme dynamic therapy (EDT). Crucially, upon NIR laser irradiation, the localized hyperthermia not only provides direct tumor ablation via photothermal therapy (PTT) but also significantly accelerates these enzymatic reaction rates. This photothermally self-enhanced synergistic strategy resulted in a tumor regression of 98.04% and 99.58% based on tumor volume and weight, respectively. This study presents a novel strategy for designing multifunctional bio-nanozymes from natural biomass and highlights the potential of integrating self-sustaining catalytic cycles with photothermal enhancement for highly effective tumor therapy.