Simple and fast batch injection analysis method for monitoring diuron herbicide residues in juice and tap water samples using reduced graphene oxide sensor

In this paper, a new analytical method was developed using batch injection analysis with ampemmetric detection and reduced graphene oxide modified glassy carbon (GCE/rGO) electrode for the simple, fast, sensitive, and effective diuron (DIU) herbicide determination in tap water and food beverages (whole juice of grape and orange) samples. The GCE/rGO sensor provided a 7.6-fold increase in the DIU electrochemical oxidation current compared to the bare electrode, which resulted in a method with good sensitivity and detectability. The developed method provided important analytical characteristics for the DIU quantification, such as detection limit of 0.36 mu mol L-1 (84 mu g L-1) below the maximum residual limit of U.S Environmental Agency, linear range from 5 to 50 mu mol L-1, good precision (RSD < 3.7 %), and accuracy (recovery levels ranging from 80.8-105.5 %). Furthermore, the minimal sample preparation (simple dilution in the supporting electrolyte) associated with a high analytical frequency (150 analyses per hour) stands out. In this sense, the proposed method proves to be an alternative analytical tool for applications in the environmental and food interest samples analysis.

Automated summary

A new analytical method was developed for the determination of diuron herbicide in tap water and food beverages using GCE/rGO sensor, providing improved sensitivity and low detection limit, with simple sample preparation.