Amino β-cyclodextrin-functionalized GS/MWCNTs for Simultaneous Electrochemical Determination of p-aminophenol and Acetaminophen

In this study, a rapid and sensitive electrochemical sensor based on amino β-cyclodextrins (NH2-β-CD) functionalized graphene and multi-walled carbon nanotubes (MWCNTs) nanohybrids was successfully constructed for the simultaneous determination of p-aminophenol (p-AP) and acetaminophen (AC). Graphene and MWCNTs were oxidized with strong acid to give carboxyl groups (COOH-f-GS/MWCNTs). Then, the NH2-β-CD was immobilized on its surface by EDC and NHS to prepare a porous hybrid nanocomposite (β-CD-NHCO-f-GS/MWCNTs). The composite material displays a well synergistic effect of high electrocatalytic activity and excellent conductivity of COOH-f-GS/MWCNTs and high supramolecular recognition capability of NH2-β-CD. The electrocatalytic mechanism and catalytic process are discussed. Under the optimum conditions, the detection limits of the as-prepared electrochemical sensor are 0.11 mM and 0.15 mM for p-AP and AC, respectively. The linear ranges are 1.0 mM to 1.32 mM for p-AP and 0.6 mM to 0.44 mM for AC. More importantly, this result was measured in the presence of each other. The electrochemical sensor can simultaneously display obvious and accurate response to p-AP and AC at different potentials with high sensitivity and less interferences.