Thermo Scientific HyperSep Dispersive SPE Products

Importance of the Topic

The analysis of pesticide residues in food matrices is critical for ensuring consumer safety and regulatory compliance. Traditional multiresidue methods often involve lengthy procedures, high costs, and significant solvent consumption. The QuEChERS method addresses these challenges by offering a rapid, cost-effective, and versatile approach to sample preparation and cleanup for a wide spectrum of pesticide chemistries.

Objectives and Overview

This application note aims to present an efficient workflow for pesticide extraction and cleanup using the QuEChERS method in combination with Thermo Scientific HyperSep dispersive SPE products. It outlines the key steps of the method, describes variations for different compound classes and sample matrices, and highlights the available SPE formats and sorbent combinations.

Methodology and Used Instrumentation

The QuEChERS protocol relies on acetonitrile extraction, salting-out partitioning, and dispersive SPE cleanup. Core steps include

• Sample extraction in acetonitrile with buffering salts to stabilize base-sensitive analytes
• Mixing and centrifugation to separate phases
• Aliquoting supernatant into dispersive SPE tubes containing sorbents such as MgSO4, PSA, C18 and graphitized carbon black for matrix cleanup
• Further centrifugation and transfer of the final extract for instrumental analysis

Variations of the method are outlined for base-sensitive compounds (AOAC 2007.01), non-base sensitive analytes (EN15662), and polar planar pigments (Schenck variation). Used Instrumentation includes centrifuge tubes, pre-prepared SPE cleanup tubes, 6mL SPE columns, HPLC and GC columns, and standard GC HPLC reagents and consumables.

Main Results and Discussion

High recoveries and reproducible results are achieved across a broad range of pesticide chemistries, including polar, non-base sensitive, and base-labile compounds. The method reduces solvent usage compared to conventional approaches and produces cleaner extracts, minimizing matrix interferences. Troubleshooting guidance addresses common issues such as loss of planar pesticides due to excessive graphitized carbon, acidic compound loss from PSA, and sample exotherms during sorbent addition.

Benefits and Practical Applications

The QuEChERS approach coupled with HyperSep dispersive SPE products delivers rapid sample throughput, flexibility in handling diverse matrices (fruits, vegetables, fatty and pigmented samples), and compatibility with both GC MS and LC MS platforms. It is well suited for routine quality control, regulatory testing, and research laboratories seeking robust and cost-effective pesticide residue analysis.

Future Trends and Opportunities

Ongoing developments may include automation of QuEChERS workflows, miniaturized and microscale adaptations to further reduce solvent consumption, integration with high-throughput screening instruments, and expansion of sorbent chemistries to target emerging contaminants beyond pesticides.

Conclusion

The QuEChERS method, enhanced by Thermo Scientific HyperSep dispersive SPE products, offers a streamlined, economical, and reliable solution for multiresidue pesticide analysis. Its versatility and high performance make it a preferred choice in modern food safety laboratories.

Reference

• Anastassiades M, Lehotay SJ Development of the QuEChERS method for pesticide residue analysis 2003
• AOAC Official Method 2007.01
• European Standard EN 15662