RAPID PASS-THROUGH SPE CLEANUP FOR MULTI-RESIDUE ANALYSIS OF FOOD MATRICES WITH HIGH LIPID AND PIGMENT CONTENT

Significance of the Topic

The rapid and selective removal of lipids, phospholipids and pigments from food matrices is essential to maintain analytical instrument performance and data quality. High levels of these interferences lead to shortened column life, ion suppression in MS detection and increased maintenance costs.

Objectives and Study Overview

This study compares a novel pass-through SPE cleanup using the Oasis PRiME HLB cartridge against traditional dispersive SPE (dSPE) sorbents (C18, PSA, GCB) for multi-residue analysis of pesticides and veterinary drugs in high-lipid and pigmented food samples.

Methodology and Instrumentation

Initial extractions were performed by QuEChERS for pesticides and acetonitrile-based protocols for veterinary drugs. Cleanup techniques evaluated:

• dSPE with octadecyl (C18) silica
• dSPE with primary/secondary amine (PSA)
• dSPE with graphitized carbon black (GCB)
• Pass-through SPE with Oasis PRiME HLB cartridges

Analysis was carried out by LC-MS/MS for veterinary drugs and acidic herbicides, and by GC-MS/MS for pesticide residues.

Key Findings and Discussion

• Oasis PRiME HLB delivered consistently high recoveries (good to excellent) for both pesticides and veterinary drugs across beef liver, avocado, spinach, soy pods and other challenging matrices.
• dSPE with PSA failed to recover acidic analytes effectively; GCB removed pigments but risked planar analyte losses at higher loadings.
• C18 showed limited removal of phospholipids and pigments compared to Oasis PRiME HLB.

Benefits and Practical Applications

Oasis PRiME HLB cleanup offers:

• Rapid, pass-through workflow in minutes without extensive solvent exchanges
• Broad applicability to fatty, phospholipid-rich and highly pigmented samples
• Compatibility with acidic pesticides not achieved by PSA dSPE
• Reduced instrument downtime and maintenance

Future Trends and Potential Applications

• Integration of pass-through SPE into automated platforms for higher throughput
• Development of tailored sorbent chemistries for emerging contaminants
• Coupling with high-resolution MS for comprehensive screening of complex matrices
• Expansion to additional food types and environmental samples

Conclusion

The Oasis PRiME HLB pass-through SPE method provides a robust, efficient and versatile cleanup alternative to conventional dSPE, ensuring high analyte recovery and effective matrix interference removal in complex food analyses.

Reference

• Waters application notes: 720005488EN, 720005730EN, 720005816EN, 720005887EN, 720005794, 720005994