An enzyme-less energy driven electrochemical approach for carbendazim detection using f-MWCNT/NTAA Na3.H2O composite in water to improve environmental sustainability

Carbendazim, a systemic fungicide, is being largely used in different sectors like, agriculture, aquaculture, forestry, and food industries. However, due to the presence of stable benzimidazole ring in it leads to the persistence of its toxic residues in the environment. Thus, the detection and quantification of carbendazim residues becomes highly imperative for early risk-assessment and decision-making. Herein, we developed a functionalized multiwalled carbon nanotube with nitrilotriacetic acid trisodium salt monohydrate (f-MWCNT/NTAA Na3·H2O) composite-based electrochemical sensor for the detection of carbendazim. From UV spectroscopy and electrochemical measurements, it has been confirmed that the interface aids in the electrocatalytic reaction towards carbendazim due to the inherent thermodynamic feasibility between the analyte and interface, and the same has been tested with density functional theory (DFT). In addition, the developed sensor showed an excellent sensing performance towards carbendazim by eliminating the effect of matrix and by recognizing the active ingredient. The sensor exhibited two distinct wide linear concentration windows in the range of 0.5–25 nM, and 0.1–500 µM with a low detection and quantification limit of 5.54, and 16.80 pM; 10.94, and 33.14 pM, respectively. The f-MWCNT/NTAA Na3·H2O modified electrode can be taken for the real-time analysis in water owing to its specificity.