Electrochemical determination of acetaminophen using a glassy carbon electrode modified with a hybrid material consisting of graphene aerogel and octadecylamine-functionalized carbon quantum dots

The study reports on the synthesis of a graphene aerogel@octadecylamine-functionalized carbon quantum dots (GA@O-CQDs). The graphene oxide aqueous dispersion, O-CQDs aqueous dispersion and toluene were strongly mixed to make a toluene-in-water Pickering emulsion. The graphene oxide sheets in the aqueous phase are reduced by hydrazine hydrate, diffuse into the toluene droplets, and self-assemble into graphene oxide microgels. This is followed by freeze-drying and thermal annealing to obtain the GA@O-CQDs hybrid that has a three-dimensional structure of several microns. It was dispersed in ethanol and deposited on a glassy carbon electrode. The modified electrode was applied to differential pulse voltammetric determination of acetaminophen, best at a peak potential of 0.15 V (vs. Ag/AgCl). Figures of the merit include a wide linear response range (0.001-10 mu M) and a 0.38 nM of the detection limit (S/N = 3). The assay has been applied to the determination of acetaminophen in tablets.