Determination of Over 300 Pesticides in Cayenne Pepper

Importance of the Topic

Cayenne pepper powder is a challenging matrix for pesticide residue analysis due to its high pigment content, fatty oils, and low moisture level. Ensuring the accurate quantification of pesticide residues in spices like cayenne pepper is essential for consumer safety, regulatory compliance, and trade.

Objectives and Study Overview

This work aimed to develop and optimize a streamlined workflow for the simultaneous determination of over 300 pesticide residues in cayenne pepper powder. The study evaluated a QuEChERS AOAC extraction followed by a pass-through cleanup using a novel sorbent blend Captiva EMR–GPD prior to both LC/MS/MS and GC/MS/MS analysis. Performance metrics such as recovery, reproducibility, matrix effects, and calibration linearity were assessed.

Methodology and Instrumentation

• Sample extraction using Agilent Bond Elut QuEChERS AOAC kit with acetonitrile acidified with 1% acetic acid and a 10% water premix to enhance acidic analyte recovery.
• Pass-through cleanup on Captiva EMR–GPD cartridges to selectively remove pigments, lipids, and acids without extensive dispersive SPE steps.
• Final dilution of extracts fivefold for LC/MS/MS; direct transfer of dried extract for GC/MS/MS after anhydrous MgSO4 drying.
• LC/MS/MS analysis on Agilent 1290 Infinity system coupled to a 6490 triple quadrupole with Jet Stream electrospray; dynamic MRM acquisition on a C18 column.
• GC/MS/MS analysis on Agilent 8890 GC with 7000E triple quadrupole, multimode inlet, midcolumn backflush, and dual HP-5ms Ultra Inert columns in parallel; dynamic MRM acquisition.

Main Results and Discussion

Captiva EMR–GPD cleanup removed approximately 60 percent of matrix co-extractives, nearly doubling the removal compared to traditional dispersive SPE. The 10 percent water premix prior to cleanup improved recoveries of acidic and polar pesticides. In six replicate tests at 5 and 50 ng per gram, over 92 percent of analytes achieved recoveries between 70 and 120 percent, more than 97 percent had relative standard deviations below 20 percent, and matrix effects were minimal. Calibration curves covering 2.5 to 2,500 ng per gram displayed strong linearity (R2 above 0.99) for 86 percent of targets, with quadratic fitting used for another 6 percent. Selected low-level pesticides showed up to fivefold signal enhancement versus dSPE cleanup.

Benefits and Practical Applications

• A simplified cleanup workflow reduces hands-on time and consumable use.
• Effective pigment and lipid removal preserves instrument and column lifetime.
• High-throughput capability supports large sample loads in food safety laboratories.
• Broad multiresidue coverage meets stringent regulatory monitoring requirements for spices.

Future Trends and Applications

Emerging sorbent technologies may further boost selectivity and expand analyte scope to include mycotoxins and veterinary drugs in spices. Integration of EMR-based cleanup with high-resolution mass spectrometry could enhance confidence in trace-level identification. Automation of pass-through cleanup with laboratory robotics will increase throughput, reproducibility, and standardization.

Conclusion

The combination of QuEChERS AOAC extraction and Captiva EMR–GPD pass-through cleanup offers a rapid, reliable solution for multiresidue pesticide analysis in complex spice matrices. The method delivers robust quantitation for over 300 pesticides via LC/MS/MS and GC/MS/MS, with excellent recovery, precision, and cleanup efficiency, supporting rigorous food safety and regulatory requirements.

References

• SANTE/11312/2021 Analytical Quality Control and Method Validation Procedures for Pesticide Residues Analysis in Food and Feed.
• Liu X et al Determination of Pesticide Residues in Chilli and Sichuan Pepper by High Performance LC QTOF MS Food Chemistry 2022 387 132915
• Liu Y et al Rapid Screening Of 27 Pesticide Residues in Chili Powder by UPLC QTOF Chinese Journal of Chromatography 2018 34(11) 1055–1062
• Andrianova A Zhao L Five Keys to Unlock Maximum Performance in the Analysis of Over 200 Pesticides in Challenging Food Matrices by GC MS MS Agilent Application Note 5994-4965EN 2022
• Agilent Technologies GC MS MS Pesticides Analyzer Agilent Application Solutions 2022
• Zhao L Wei T Determination of Multiclass Multiresidue Pesticides in Spring Leaf Mix Using Captiva EMR HCF Cleanup and LC MS MS Agilent Application Note 5994-4765EN 2022
• Zhao L Determination of Multiclass Multiresidue Pesticides in Tree Nuts by Captiva EMR LPD Passthrough Cleanup and LC MS MS Agilent Application Note 5994-5129EN 2022