Optimization and Validation of a GC-FID/QuEChERS Method for Quantitative Determination of Spiromesifen Residues in Tomato Fruits, Leaves and Soil Matrices

Pesticides serve a crucial function in contemporary farming practices, safeguarding agricultural crops against pest infestations and boosting production outputs. However, indiscriminate use has caused environmental and human health damage. The aim of this study was to develop and validate a gas chromatography-flame ionization detection (GC-FID) methodology for the direct and routine analysis of spiromesifen residues in soil, leaves and tomato fruits. The proposed method prioritizes simplicity by avoiding derivatization steps, offering advantages over existing approaches that utilize lengthy multi-step extraction or derivatization prior to GC analysis. A key novelty of this work is the development of a QuEChERS extraction coupled directly to GC-FID without further clean-up or chemical treatment steps, rendering the method more convenient and accessible for routine monitoring applications. Factors evaluated included: sample solvent; inlet and column temperature profiles; inlet type; sample volume; and injection technique. Recovery and matrix effect studies were conducted by fortifying tomato, leaf, and soil matrices at three different concentrations (۰.۵, ۱, and ۱۰ µg/mL). Quadruplicate analyses (n=۴) yielded mean recoveries of ۹۸.۷۴% (fruits), ۹۳.۹۲% (leaves), and ۹۴.۱۸% (soil), confirming efficient extraction. Matrix effects were negligible at -۷.۹%, -۷.۸% and -۵.۳%, respectively. Chromatographic linearity of developed GC-FID method was excellent over the ۰.۰۰۲-۲۰ µg/mL range with R۲ > ۰.۹۹۷۹. The method demonstrated good precision, with inter- and intra-day RSD% ranging from ۰.۰۶-۱.۸%, below the ۳% limit. GC-MS analysis confirmed spiromesifen identification. Under greenhouse conditions, residual levels were ۱.۳۹ mg/kg in soil, ۸.۲۴ mg/kg in tomato, and ۳.۳۹ mg/kg in leaves.

کلیدواژه ها:

GC-FID ، Pesticide residues ، QuEChERS ، Spiromesifen ، Tomato matrices