Dual-activity nanozyme as an oxygen pump to alleviate tumor hypoxia and enhance photodynamic/ NIR-II photothermal therapy for sniping oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is the most common malignant tumor in the head and neck region, and its treatment is limited by hypoxia and inadequate oxygen supply. Continuous oxygen delivery combined with photodynamic therapy (PDT) is the key to addressing this issue. Here, a dual-enzyme activity sea urchin-like Au@Pt-Ce6-HN-1 nanoplatform was designed to serve as an "oxygen pump" to alleviate tumor hypoxia for synergistic photodynamic/photothermal therapy (PTT). In this design, the photosensitizer chlorin e6 (Ce6) is covalently linked to the Au@Pt nanozyme for PDT treatment. The Au@Pt nanozyme exhibits catalase-like activity, continuously decomposing H