Sensitive and accurate determination of isodrin in broccoli powder using a combination of spray-assisted droplet formation-based liquid phase microextraction and gas chromatography-mass spectrometry

Abstract

The intensification of agricultural activities has led to increased chemical exposure in ecosystems, with pesticides playing a key role in enhancing agricultural productivity. However, their use also poses significant risks to human health and environmental stability. This study focuses on the determination of trace levels of isodrin, a representative insecticide, using gas chromatography-mass spectrometry (GC-MS). The spray-assisted droplet formation-based liquid phase microextraction (SADF-LPME) method was optimised for the detection of isodrin under suitable chromatographic conditions. Five validation parameters - limit of detection (LOD), limit of quantification (LOQ), percent relative standard deviation (%RSD), linear range (LR), and coefficient of linear regression (R2) - were evaluated to ensure accuracy. The method demonstrated excellent performance, with LOD and LOQ values of 2.24 and 7.47 ng g-1, respectively. Isodrin was successfully extracted from broccoli powder samples using acetonitrile, with no analytical signal detected at the expected retention time. The method's accuracy and applicability to real samples were confirmed through recovery experiments, yielding recovery rates between 92.2% and 108.9% for spiked concentrations within the linear range. A matrix-matching calibration strategy was employed to enhance the quantification accuracy.