▎ 摘　　要

NOVELTY - A modified electrode preparation method involves polymerizing carboxylated graphene with pyrrole to obtain carboxylated graphene-polypyrrole. The carboxylated graphene-polypyrrole is dissolved in chitosan solution, followed by ultrasonic treatment to obtain carboxylated graphene-polypyrrole-chitosan mixture. The carboxylated graphene-polypyrrole-chitosan mixture is titrated onto glassy carbon electrode, followed by drying to obtain carboxylated graphene-polypyrrole-chitosan modified electrode. USE - Method for preparing modified electrode for detecting ion concentration. ADVANTAGE - The method enables preparing modified electrode with high stability and high reproducibility in a simple manner by utilizing for rapidly and accurately detecting ion concentration. DETAILED DESCRIPTION - A modified electrode preparation method involves polymerizing carboxylated graphene with pyrrole to obtain carboxylated graphene-polypyrrole. The carboxylated graphene-polypyrrole is dissolved in 5 mass% chitosan solution, followed by ultrasonic treatment to obtain carboxylated graphene-polypyrrole-chitosan mixture. The carboxylated graphene-polypyrrole-chitosan mixture is titrated onto glassy carbon electrode, followed by drying to obtain carboxylated graphene-polypyrrole-chitosan modified electrode, where 2.5-4.5 mg carboxylated graphene-polypyrrole is dissolved in 5 mass% chitosan solution.