Fluorometric detection of copper and imidacloprid using nitrogen-doped graphitic carbon dots: A promising method for environmental monitoring

Abstract

Pesticides in environmental samples pose significant risks to ecosystems and human health since they require precise and efficient detection methods. Imidacloprid (IMI), a widely used neonicotinoid insecticide, exemplifies these hazards due to its potential toxicity. This study addresses the urgent need for improved monitoring of such contaminants by introducing a novel fluorometric method for detecting IMI using nitrogen-doped graphite carbon dots (N-GCDs). The sensor operates by quenching fluorescence through the interaction of Cu²⁺ ions with N-GCDs. Subsequently, IMI binds to the imidazole group, chelates with Cu²⁺, and restores the fluorescence of N-GCDs. This alternating fluorescence behavior allows for the accurate identification of both Cu²⁺ and IMI. The sensor exhibits linear detection ranges of 20-100 nM for Cu²⁺ and 10-140 μg/L for IMI, with detection limits of 18 nM and 1.2 μg/L, respectively. The high sensitivity of this sensor enables the detection of real-world samples, which underscores its potential for practical use in environmental monitoring and agricultural safety.

Keywords: copper ions; environmental monitoring; fluorometric detection; imidacloprid.