In Situ Redox-Omics Decoding of Nanoparticle–Protein Corona Interactions Drives the Mitochondrial Metabolic-Immunological Mechanism in Microglia

Nanoparticle–protein corona interactions critically determine biological responses but remain poorly characterized in living systems due to the lack of noninvasive analytical tools. In this study, we developed a redox-omics strategy that facilitated the in situ mapping of corona composition by tracking cysteine thiol oxidation markers induced by nanoparticles. As a research tool, we synthesized natural-organic-matter-derived carbon dots (nCDs) with dual superoxide dismutase/catalase-mimetic activity. A global redox-omics analysis identified 104 proteins that demonstrated significant redox reactions in response to treatment with nCDs. In particular, we found that nCDs specifically induced a conformational change in isocitrate dehydrogenase 1 (IDH1) by selectively reversing the oxidation of cysteine 269 (Cys 269 ). In the mechanism, the site-specific reduction in cysteine 269 (Cys 269 ) triggered a conformational switch of IDH1 that restored mitochondrial α-ketoglutarate flux and NADPH homeostasis, thereby blocking cytosolic mitochondrial DNA (mtDNA) leakage and subsequent cGAS-STING-driven neuroinflammation. Crucially, the nCDs-mediated metabolic checkpoint control inhibited the pro-inflammatory (M1) phenotypes of microglia, thereby achieving therapeutic efficacy in both zebrafish and murine ischemic stroke models, without inducing detectable toxicity. Collectively, we developed a label-free platform enabling in situ decoding of protein corona interactions via redox-sensitive cysteine profiling, eliminating the need for nanoparticle surface modifications.