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

Importance of the Topic

Effective removal of lipids, phospholipids and pigments from complex food matrices is essential to safeguard analytical instrumentation and ensure reliable multi-residue determinations of pesticides and veterinary drugs. Simplified and rapid cleanup approaches reduce sample preparation time, increase throughput, and lower operational costs in food safety laboratories.

Study Objectives and Overview

This work evaluates a rapid pass-through SPE cleanup technique using Oasis PRiME HLB cartridges and compares its performance with traditional dispersive SPE sorbents for QuEChERS extracts of high-fat and pigment-rich foods. The study focuses on recovery rates, matrix interference removal, and applicability to acidic analytes.

Methodology and Instrumentation

Samples of avocado, beef liver, salmon, shrimp, infant formula, spinach and soybean pods were extracted using standard QuEChERS or acetonitrile-based protocols. Cleanup options included dispersive SPE with C18, primary secondary amine (PSA) and graphitized carbon black (GCB), and pass-through SPE using Oasis PRiME HLB cartridges. Instrumental analysis was performed by LC-MS/MS and GC-MS/MS.

• Extraction: QuEChERS and acetonitrile partitioning
• Cleanup sorbents: C18 silica, PSA, GCB
• Pass-through cartridge: Oasis PRiME HLB
• Detection: LC-MS/MS for veterinary drugs and acidic pesticides; GC-MS/MS for non-polar pesticides

Main Results and Discussion

Oasis PRiME HLB consistently delivered good to excellent recoveries while effectively eliminating matrix components that challenge column integrity and ionization.

• Fat removal: PRiME HLB and C18 provided the best cleanup, while PSA was poor and GCB was fair.
• Phospholipid removal: PRiME HLB showed superior performance; PSA was acceptable but only for non-acidic analytes; C18 and GCB were ineffective.
• Carotenoid and pigment removal: PRiME HLB matched or outperformed GCB without compromising planar analyte recovery; PSA and C18 were inadequate for chlorophyll cleanup.
• Acidic herbicides in soybean pods: Only PRiME HLB achieved quantitative recovery; PSA failed to retain acidic analytes.

Overall, pass-through SPE minimized lipid- and pigment-related suppression and extended LC and GC column lifetimes.

Benefits and Practical Application

The Oasis PRiME HLB cleanup approach offers significant advantages for routine food analysis:

• Short processing time of only a few minutes per sample
• High recovery of diverse pesticide and veterinary drug classes, including acidic compounds
• Improved instrument uptime and reduced maintenance costs
• Compatibility with both low- and high-throughput laboratory workflows

Future Trends and Potential Applications

Advances in sorbent chemistry and automated pass-through SPE platforms promise even faster sample prep and broader analyte coverage. Integration with online cleanup systems and miniaturized cartridges could further reduce solvent use and waste. Emerging food matrices with novel lipids and pigments will drive development of customized cleanup solutions based on PRiME HLB technology.

Conclusion

Pass-through SPE cleanup using Oasis PRiME HLB cartridges is a robust, efficient alternative to traditional dispersive SPE for complex food samples. It ensures high analyte recovery, effective matrix removal and operational efficiency for both pesticide and veterinary drug multi-residue analyses.

Reference

• Young MS, Tran K, Shia JC. Rapid pass-through SPE cleanup for multi-residue analysis of food matrices with high lipid and pigment content. Waters Corporation Poster 2017.
• Waters application notes: 720005488EN, 720005730EN, 720005816EN, 720005887EN, 720005794EN, 720005994EN.