Development of a high-efficiency QuEChERS protocol with fluorinated halloysite nanotubes adsorbent for selective and robust detection of pesticide residues in high-risk vegetables via GC-MS/MS

This study presents the rational design and application of fluorinated halloysite nanotubes (HNTs-F) as a high-performance adsorbent within a modified QuEChERS method for the sensitive and reliable determination of pesticide residues in high-risk vegetable matrices using gas chromatography-tandem mass spectrometry (GC-MS/MS). To evaluate the impact of surface functionalization on purification efficiency, a series of chemically modified halloysite nanotubes (HNTs-F, HNTs-NH2 and HNTs-NHCONH2) were systematically assessed in terms of recovery and matrix effect (ME). Among the adsorbents examined, HNTs-F emerged as the most effective, significantly minimizing co-extracted matrix interferences and thereby enhancing analytical accuracy and instrument response stability. The optimized protocol yielded excellent pesticide recoveries ranging from 81.1 % to 113.9 %, with low RSD of ≤ 8.7 %, indicating high precision and reproducibility. The method exhibited robust linearity (R2 > 0.9990) across relevant concentration ranges, alongside outstanding sensitivity, with LOD and LOQ spanning 0.03-2.5 μg/kg and 0.1-7.0 μg/kg, respectively. These results underscore the significant potential of HNTs-F as a promising adsorbent in QuEChERS-based sample preparation, offering enhanced cleanup efficiency and sensitivity for trace-level monitoring of pesticide residues in vegetable matrices.