Some progress in developing electrochemical sensors for detection of 2,4-dichlorophenoxyacetic acid based on modified carbon interfaces: a brief review

The herbicide 2,4-dichlorophenoxyacetic acid (2,4-DPAA) is commonly used in agricultural practices. Unfortunately, it has a high toxicity level and is known to be a carcinogenic substance. Therefore, developing an analytical technique capable of detecting this com­pound is crucial. Electrochemical methods offer a viable solution for the rapid and on-site analysis of 2,4-DPAA residues in real samples. The detection of 2,4-DPAA can be achieved through electrochemical redox electron transfer reactions, making voltammetry an effective approach. Various studies have explored the use of carbon electrodes, such as glassy carbon electrodes (GCE), carbon paste electrodes (CPE), and screen-printed electro­des (SPE), for voltammetric detection of 2,4-DPAA. However, researchers have encountered challenges in detecting 2,4-DPAA using these carbon electrodes. Consequently, modifi­cations have been made to the carbon materials by incorporating chitosan hierarchical porous silica, Fe3O4-polyaniline nanocomposites, silver, manganese oxide nano­particles, alizarin yellow R polymer, hierarchical porous calcium phosphate, and molecularly im­printed polypyrrole with TiO2 nanotubes. In this comprehensive review, we have examined the effectiveness of each modified electrode, considering factors such as the limit of detection, precise linear range, and recovery rate for detecting 2,4-DPAA in real samples.