Engineering Fe–N Doped Graphene to Mimic Biological Functions of NADPH Oxidase in Cells

NADPH oxidase (NOX) as a transmembrane protein complex controls the generation of superoxide that plays important roles in immune signaling pathway.NOX inactivation may elicit immunodeficiency and cause chronic granulomatous disease (CGD).Biocompatible synthetic materials with NOX-like activities would therefore be interesting as curative and/or preventive approaches in case of NOX deficiency.Herein, we synthesized a Fe-N doped graphene (FeNGR) nanomaterial that could mimic the activity of NOX by efficiently catalyzing the conversion of NADPH into NADP + and triggering the generation of oxygen radicals.The resulting FeNGR nanozyme had similar cellular distribution to NOX, and is able to mimic the enzyme function in NOXdeficient cells by catalyzing the generation of superoxide and retrieving the immune activity, evidenced by IL-1β and TNF-α production in response to Alum exposure.Overall, our study discovered the first synthetic materials to mimic NOX and demonstrated the enzyme function of FeNGR nanozyme in cells.