β-cyclodextrin and ZnCo-layered double hydroxides composite modified electrode for ultrasensitive detection of...

Detecting carbendazim (CBZ) poses a significant challenge, which underscores the urgency for reliable monitoring methods. To address this, we have developed a high-performance electrochemical sensor to detect CBZ. This sensor achieves this through the integration of β-cyclodextrin (β-CD, for selective adsorption) and zinc-cobalt layered double hydroxides (ZnCo-LDHs, for efficient catalysis and electron transfer). Comprehensive characterization and density functional theory (DFT) calculations revealed a synergistic effect. The adsorption energy of CBZ by β-CD is 3.4 times higher than that by ZnCo-LDHs, thereby enabling targeted enrichment. ZnCo-LDHs reduces the electrode charge transfer resistance by 2.69 times to enhance electron transfer. This sensor achieves a wide linear response (0.005-1 mg/L), a detection limit of 0.35 μg/L, and a quantitative limit of 1.17 μg/L. It also exhibits a high sensitivity of 111.99 μA·μM⁻¹ ·cm⁻², along with excellent selectivity, stability, and reproducibility. The recovery rates in tap water, river water, and groundwater range from 94.50 % to 105.22 % (RSD≤8.20 %). Comparison with liquid chromatography-mass spectrometry analysis confirmed its reliability. This work provides a powerful platform for rapid, on-site pesticide monitoring in aquatic environments, offering a viable strategy to mitigate contamination risks and advance sustainable environmental management.