Developing an electrochemical sensor for the detection of tert-butylhydroquinone

In the work, a ratiometric electrochemical sensor for tert-butylhydroquinone (TBHQ) detection is constructed based on the modified electrode consisting of manganese dioxide (MnO2) and electrochemically reduced graphene oxide (ERGO) nanocomposite film. MnO2 was electrodeposited onto the electrochemically reduced graphene oxide (ERGO) placed on a glassy carbon electrode (GCE) to form the MnO2/ERGO/GCE. The construction process of the MnO2/ERGO/GCE electrode was characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and Raman spectroscopy. The electrochemical signal responses of the TBHQ sensor were recorded by differential pulse voltammetric measurements. The experimental results demonstrate that MnO2 can be used as the inner reference electrochemical probe, and ERGO can improve the sensitivity for TBHQ detection. It can be found that as the TBHQ concentration increases, the anodic peak current of TBHQ at the MnO2 /ERGO/GCE increases, but the anodic peak current of MnO2 at such the modified electrode almost remains unchangeable. The net peak current ratio between TBHQ and MnO2 is chosen for quantitative detection of TBHQ. The developed ratiometric sensor exhibits two linear ranges of 1.0-50.0 mu M and 100.0-300.0 mu M for detecting TBHQ. The detection limit for TBHQ detection is estimated to be 0.8 mu M on the basis of signal-to-noise (S/N) of 3. Moreover, the ratiometric electrochemical sensor is successfully applied for TBHQ detection in real edible oil samples.