High-Throughput Quantification of Pesticide Residues in Complex Matrix (Chili Powder) Using Liquid Chromatography Tandem Mass Spectrometry: Inter- and Intra-Day Validation.

BACKGROUND

Chili powder is a widely consumed spice; however, during cultivation chili crops are often subjected to pesticide treatments to control pests and diseases. Thus, monitoring pesticide residues in such matrixes is crucial for food safety and to comply with national as well as international regulations for export/import purposes. However, accurate analysis of pesticide residue in chili powder is challenging due to its complex nature.

OBJECTIVE

To develop and validate a high-throughput LC-MS/MS method for the quantification of multiclass pesticide residues in a complex chili powder matrix.

METHODS

The acetonitrile-based extraction method was optimized for chili powder samples. The targeted analytes were separated using reverse-phase liquid chromatography and detected using tandem mass spectrometry. Validation was conducted following SANTE guidelines to comply with regulatory requirements.

RESULTS

The method with an optimized sample preparation workflow demonstrated a lower matrix effect of <35% for the target pesticides. The LOQ was determined to be 0.005 mg/kg for 135 analytes, with recovery ranging from 70 to 110%, and intra-day and inter-day precision (RSD) were below 15%. Analysis of market/incurred samples and measurement uncertainty further provided more confidence in the method performance.

CONCLUSIONS

The developed LC-MS/MS method provides a robust, sensitive, and high-throughput approach for the quantification of pesticide residues in complex chili powder. Its intra- and inter-day validation confirms suitability for routine analysis in food safety laboratories.

HIGHLIGHTS: A high-throughput LC-MS/MS method is developed for pesticide analysis in complex chili powder. The method was validated according to SANTE 11312/2021-v2 with excellent precision and accuracy. Suitable for routine food safety monitoring of a wide range of pesticide residues in a testing laboratory.