Selective sensing of hydroquinone and catechol based on multiwalled carbon nanotubes/polydopamine/gold nanoparticles composites

In this work, a highly sensitive and selective electrochemical sensor based on multiwalled carbon nanotubes/polydopamine/gold nanoparticles composites (MWCNTs/PDA/AuNPs) and chitosan (CS) was developed, which was used for simultaneous determination of hydroquinone (HQ) and catechol (CC) derived from a large specific area of MWCNTs and superexcellent electroconductibility of AuNPs. It was found that HQ and CC could be completely separated on the electrode using cyclic voltammetry and differential pulse voltammetry technique under optimal conditions. The proposed sensor based on MWCNTs/PDA/AuNPs exhibited linear responses for HQ and CC from 0.1 to 10   μmol   L −1 with detection limits (S/N   =   3) of 0.035   μmol   L −1 and 0.047   μmol   L −1 , respectively. In addition, the modified electrode was successfully implemented in the simultaneous determination of CC and HQ in tap and lake water samples. And compared with other methods, this sensor exhibited good sensitivity, stability and reproducibility.