▎ 摘　　要

Amaranth has obtained tremendous attention due to high toxicity and widespread use, and it is worthwhile to develop sensitive and rapid determination methods for amaranth. Herein, a kind of graphene nanosheets (GS) were prepared through ultrasonic exfoliation of graphite powder in N-methyl-2-pyrrolidone (NMP) and then used to construct a highly sensitive determination platform for amaranth. In pH 4.6 acetate buffer solution, a greatly enhanced oxidation wave at 0.74 V is observed for amaranth on the surface of GS. The influences of pH value, amount of GS modification, accumulation potential, and time on the oxidation peak currents of amaranth were examined. As a result, a simple and rapid electrochemical method has been proposed for the determination of amaranth. The linear range is from 2.5 to 125 nM, and the detection limit is as low as 0.75 nM. This sensing platform was used in different drink samples, and the results consist with the values that obtained by high-performance liquid chromatography.