Sequential Unlocking of an RNS/ROS Storm via a Four-Layer Logic‑Gated Ruthenium Nanocomposite for Hypoxia-Tolerant Photodynamic Cancer Immunotherapy.

Abstract

Tumor hypoxia, an immunosuppressive microenvironment, and the lack of spatiotemporally precise therapeutic activation collectively limit current cancer treatments. Here, we report a smart nanocomposite (G&Ru@CuS) that produces a localized reactive nitrogen species (RNS)/reactive oxygen species (ROS) storm controlled by four sequential logic gates. (i) Intracellular ROS degrade a thioketal-crosslinked polymer gatekeeper, exposing the hollow CuS core. (ii) Acidic tumor pH (6.5-6.8) and high glutathione (GSH) trigger release of Cu²⁺, the NO donor S-Nitrosoglutathione (GSNO), and a NO-responsive mitochondria-targeted prodrug photosensitizer Ru1 from the a degradable CuS scaffold. (iii) Cu²⁺ catalyzes NO generation from GSNO. (iv) NO reacts with Ru1 to form Ru2. Ru2 is an NO-responsive prodrug photosensitizer that, upon activation, displays dual Type I/II photodynamic activity. It retains efficacy under hypoxia, rapidly depletes GSH, oxidizes NADH, and shows photocatalytic peroxidase activity, making it a powerful agent for triggering an RNS/ROS storm that drives tumor cell mitochondrial damage, necroptosis and ferroptosis, resulting in immunogenic cell death that promotes dendritic cell maturation and systemic antitumor immunity. In murine models, intravenous G&Ru@CuS achieves potent tumor inhibition with excellent immunotherapy and no systemic toxicity. This work is the first quadruple logic-gated nanoplatform that overcomes hypoxia, enables spatiotemporal precision, and minimizes off-target effects.