▎ 摘　　要

NOVELTY - Carbon nanoparticle has a graphene-like structure and contains a hydrophilic group. USE - Carbon nanoparticle for scavenging free radicals used as free radical scavenger in protection of gastrointestinal radiotherapy orally (all claimed). ADVANTAGE - The carbon nanoparticle realizes safe and efficient radiotherapy protection for the gastrointestinal tract. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method for preparing carbon nanoparticles, which involves: (A) adding carbon raw materials and oxidant to a reaction vessel; (B) refluxing at 85-95 degrees C for 5-24 hours; (C) cooling at room temperature to perform the centrifugation; (D) discarding precipitate to leave supernatant; and (E) performing another centrifugation of the supernatant to obtain precipitate as carbon nanoparticles.