Zinc Oxide Nanoparticles as Antifouling Materials for the Electrochemical Detection of Methylparaben

The use of personal care products (PCPs) containing methylparaben (MePa) has been linked with coral reef damage, breast cancer, and endocrine disruption. To monitor such pollutants, the development of simple, fast, and sensitive detection methods is needed. This study reports the electrochemical detection of MePa using a zinc oxide (ZnO) nanoparticle modified glassy carbon electrode. We addressed two main challenges posed by the use of sensing electrodes, that is, the instant fouling of electrodes for the detection of phenolic compounds and the use of expensive or highly complex, multicomponent materials for the detection of water contaminants. By controlling the pH of the reaction solution, ZnO nanoparticles with three different morphologies were synthesized: nanowires, nanocuboids, and nanospheres. The impact of these morphologies on the performance and sensitivity of the fabricated modified electrode was investigated. Under optimum conditions, ZnO nanowires demonstrated the best response compared to the other geometries, with a linear calibration response in the range of 0.02-0.12 mM, and the lowest limit of detection (LOD) of 7.25 mu M. The proposed sensor not only offers simplicity and the use of low-cost materials, but also successfully overcomes the electrode passivation associated with phenol-containing chemicals and can, therefore, be an attractive candidate for further antifouling applications.

Automated summary

This study demonstrated the electrochemical detection of MePa using a ZnO nanoparticle modified glassy carbon electrode. Three different morphologies of ZnO nanoparticles were synthesized by controlling the pH of the reaction solution. Among them, ZnO nanowires showed the best response, with the highest sensitivity and lowest limit of detection under optimal conditions.