▎ 摘　　要

NOVELTY - A substrate is made of graphene oxide-grafted 4-vinyl-boronic acid which is obtained by dispersing 4-vinyl-phenylboronic acid, bromide functionalized graphene oxide, copper bromide and pentamethyl divinyl triethylamine in 1,4-dioxane under nitrogen, stirring at room temperature for 24 hours, washing reaction product and vacuum-drying. The mass ratio of 4-vinyl-phenylboronic acid, bromide functionalized graphene oxide, copper bromide and pentamethyl divinyl triethylamine is 1:1-5:0.2-0.6:0.2-0.6. USE - Substrate is used for matrix-assisted laser desorption-ionization time-of-flight mass spectrometry for detecting sugar, phenol and nucleoside. ADVANTAGE - The substrate provides matrix-assisted laser desorption-ionization time-of-flight mass spectrometry having high selectivity and sensitivity.