Nontarget and high-throughput screening of pesticides and metabolites residues in tea using ultra-high-performance liquid chromatography and quadrupole-orbitrap high-resolution mass spectrometry

This study developed a novel Sin-QuEChERS method coupled with Ultra-High-Performance Liquid Chromatography (UHPLC) and Q-Exactive Orbitrap Mass Spectrometry (MS) for the nontargeted, high-throughput screening and quantitative analysis of pesticide and metabolite residues in green tea. The method involved extracting samples with 0.1% formic acid in acetonitrile, followed by salting out, centrifugation, and purification using a Sin-QuEChERS Nano solid phase extraction column. Data acquisition was performed in Full MS/ddMS2 mode, and a database containing 384 pesticides was used with Trace Finder 3.0 software for rapid screening and confirmation based on accurate mass, isotope abundance ratio, and secondary fragment ions. The method was validated using 20 quality control pesticides, demonstrating linearity between 1 and 200 μg/L with correlation coefficients greater than 0.9922. The Limit of Quantification (LOQ) ranged from 0.002 to 0.01 mg/kg, and average recoveries for spiked tea samples were between 74% and 111%. The efficiency and reliability of the method were confirmed by analyzing 38 Chinese green tea samples, leading to the detection of 18 potential residual pesticides through nontargeted screening, which were subsequently quantified.

This study developed a novel Sin-QuEChERS method coupled with Ultra-High-Performance Liquid Chromatography (UHPLC) and Q-Exactive Orbitrap Mass Spectrometry (MS) for the nontargeted, high-throughput screening and quantitative analysis of pesticide and metabolite residues in green tea. The method involved extracting samples with 0.1% formic acid in acetonitrile, followed by salting out, centrifugation, and purification using a Sin-QuEChERS Nano solid phase extraction column. Data acquisition was performed in Full MS/ddMS2 mode, and a database containing 384 pesticides was used with Trace Finder 3.0 software for rapid screening and confirmation based on accurate mass, isotope abundance ratio, and secondary fragment ions. The method was validated using 20 quality control pesticides, demonstrating linearity between 1 and 200 μg/L with correlation coefficients greater than 0.9922. The Limit of Quantification (LOQ) ranged from 0.002 to 0.01 mg/kg, and average recoveries for spiked tea samples were between 74% and 111%. The efficiency and reliability of the method were confirmed by analyzing 38 Chinese green tea samples, leading to the detection of 18 potential residual pesticides through nontargeted screening, which were subsequently quantified. Research Background and Significance Pesticide residues in food products, particularly in tea, are a major concern for environmental safety and public health. Tea plants are susceptible to a wide range of pesticides, which can accumulate in the final consumable product. Traditional pesticide residue analysis often relies on targeted methods that detect known pesticides, limiting the ability to identify unknown or emerging contaminants. The increasing complexity of environmental matrices and the demand for rapid, comprehensive monitori