▎ 摘　　要

NOVELTY - Surface self-assembled nano-graphene oxide probe, is claimed. The probe is obtained by combining water-soluble graphene oxide with a nitrone free radical capture probe through electrostatic adsorption, where the number of ethylene oxide unit is 3-30, and the nitrone free radical capture probe is N-(phenylmethylene)benzenamine N-oxide (preferred), 4-tert-butyl benzyl N-oxide or 4-hydroxybenzyl N-oxide. USE - The water-soluble surface self-assembled nano-graphene oxide probe is useful for capturing free radicals e.g. hydroxy radicals and superoxide anions, and for preparing free radical-capturing agents (claimed). ADVANTAGE - The probe can capture the free radicals under low concentration by self-assembling the nitrone free radical probe on the surface of the nano-graphene particles and locally forming a high-concentration of nitrone free radical probe groups at the graphene surface. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: (1) preparing the surface self-assembled nano-graphene oxide probe, comprising performing hydroxyethylation reaction and self-assembling of nitrone free radical capture probe and water-soluble graphene oxide to obtain the product; (2) a water-soluble graphene oxide; and (3) preparing the water-soluble graphene oxide, comprising dissolving graphene oxide in water, regulating the pH of the reaction system to 10-12 by using a pH regulating agent and reacting with ethylene oxide to obtain the product.