▎ 摘　　要

NOVELTY - A ferrocene-based aptamer biosensor preparing method involves utilizing sensor i.e. screen-printed carbon electrode, modifying a graphene oxide-chitosan composite film on the surface of a ferrocene-labeled hairpin aptamer and fixing on the surface of the screen-printed carbon electrode to complete the construction of the aptamer sensor. USE - Method for preparing ferrocene-based aptamer biosensor for use as electron donor for detecting organic phosphorus pesticide (claimed) such as profenofos, phorate, isocarbophos, and omethoate. ADVANTAGE - The ferrocene-based aptamer biosensor realizes ultra-sensitive detection, short detection time and low detection limit of organic phosphorus pesticide.