GTP-Modified Gold Nanoparticle-Based Four-Core Fiber Sensor for Ultrasensitive Detection of Chlorothalonil in Environmental and Food Safety Monitoring

In this study, an ultrasensitive, and glyceraldehyde-3-phosphate dehydrogenase (GTP)-modified gold nanoparticles (AuNPs)-based localized surface plasmon resonance (LSPR) sensor for detection of chlorothalonil (CTL) in environmental and food safety applications. As a widely used fungicide, CTL plays an important role in agricultural production. However, its residues pose a potential threat to environmental ecology and human health. Therefore, it is particularly urgent and significant to develop an efficient and sensitive detection method for CTL. In this study, an innovative detection method of CTL is proposed based on LSPR sensor. A highly sensitive LSPR sensor was successfully constructed by carefully synthesizing AuNPs and modifying them with GTP. The sensor demonstrates high sensitivity, evidenced by its low limit of detection (LoD) for CTL and exhibits excellent selectivity and stability. More importantly, the recovery rate of the detection method in actual samples reached more than 90 %, which fully proved its broad application prospects in the field of environmental monitoring and food safety. The linear range of the sensor is 0-1000 μM, and the LoD is 75.41 μM. The sensitivity is as high as 0.0037 nm/(μM), which verifies that the sensor provides an indispensable technology and a cost-effective and portable solution for CTL-specific detection.