▎ 摘　　要

High concentration graphene nanosheets were easily prepared through simple liquid-phase exfoliation of graphite powder in N,N-dimethylformamide with the assistance of sodium gallate (SG). The concentration of the obtained graphene dispersion reached 2.0 mg mL(-1) only after three hours of ultrasonic treatment. Sodium gallate-exfoliated graphene nanosheets (SG-GNs) showed remarkable signal enhancement effects toward the oxidation of guaiacol and vanillin. In this regard, the composite was used to develop a sensitive and rapid electrochemical method for simultaneous determination of guaiacol and vanillin. The method had a wide linear range of 0.02-12 mu M for guaiacol and 0.02-11 mu M for vanillin, and low limits of detection of 5 and 4.5 nM, respectively. The developed sensor also exhibited superior accuracy for analysis of real food samples. Therefore, the proposed sodium gallate-assisted exfoliation strategy shows great potential for scalable preparation of graphene suspensions and electrochemical sensing.