Keep Your Instruments Up and Running with CarboPrep Plus SPE Cartridges

Importance of the Topic

Environmental laboratories analyzing organochlorine pesticides often face costly instrument downtime caused by inlet and column contamination. Efficient sample cleanup is critical to protect analytical systems, ensure data quality, and meet tight project deadlines.

Study Objectives and Overview

This study compares traditional Florisil SPE cartridges with Restek’s new CarboPrep Plus SPE cartridges for cleaning soil and water extracts prior to GC analysis of organochlorine pesticides. The goal is to assess contaminant removal efficiency, instrument protection, and workflow compatibility.

Methodology and Instrumentation

Both cleanup methods use identical conditioning, loading, and elution steps with hexane:acetone (90:10). Samples are loaded onto SPE cartridges and eluted into a 10 mL collection volume. Extracts are analyzed by gas chromatography with electron capture detection to evaluate analyte recovery and background levels.

Used Instrumentation

• Gas chromatograph: Agilent/HP6890 GC equipped with micro-ECD.
• Column: Rtx-CLPesticides, 30 m × 0.32 mm ID × 0.32 µm film.
• Injection: 4 µL splitless at 250 °C with 0.75 min hold; Topaz inlet liner w/ wool.
• Carrier gas: Helium constant flow 3.5 mL/min; make-up gas N₂ at 50 mL/min.
• Oven program: 90 °C (0.5 min) to 330 °C at 25 °C/min (2 min hold).

Key Results and Discussion

CarboPrep Plus cartridges extended instrument run times more than twofold compared to Florisil by removing high-molecular-weight matrix components that foul inlets and columns. Recoveries for 20 organochlorine pesticides and surrogate compounds ranged from 94.6 % to 101.2 % with RSDs below 5.5 %, demonstrating excellent accuracy and precision. Lot-to-lot consistency studies confirmed reliable elution of all target compounds within the 10 mL volume.

Benefits and Practical Applications

• Significant reduction in unscheduled maintenance and replacement of inlet liners and columns.
• Higher sample throughput due to longer uninterrupted analysis sequences.
• Seamless integration into existing Florisil workflows using the same solvents, volumes, and manifolds.
• Consistent performance across cartridge lots simplifies method validation and routine operation.

Future Trends and Opportunities

Further development of SPE sorbents may target broader classes of nonvolatile matrix interferences, enabling reliable cleanup for emerging contaminants. Automation of SPE workflows and integration with on-line cleanup modules could streamline high-throughput analysis.

Conclusion

CarboPrep Plus SPE cartridges offer a straightforward upgrade from Florisil cleanup for organochlorine pesticide analysis. By effectively removing fouling contaminants and maintaining high recoveries, they safeguard GC instrumentation, improve laboratory productivity, and ensure consistent analytical performance.