Preparative Fraction Collector - PFC

Significance of the Topic

The isolation of pure compounds following capillary gas chromatography is critical for advanced structural and quantitative analyses. Preparative fraction collectors enable researchers to obtain sufficient quantities of analytes for techniques such as NMR and IR spectroscopy, support method development, and ensure high reproducibility in trace-level investigations.

Study Objectives and Overview

This application note presents the GERSTEL Preparative Fraction Collector (PFC) designed to automatically collect individual compounds, compound series, or chemical classes after GC separation. The objective is to demonstrate the PFC’s integration with GC/MS systems, its operational precision, and its ability to deliver high recovery rates for downstream analyses.

Methodology and Instrumentation

The GERSTEL PFC employs microprocessor control to switch between six temperature-controlled traps and one waste trap with 0.01-minute resolution. Traps are available in 1 µl and 100 µl volumes. Optional liquid nitrogen or cryostatic cooling enhances retention of volatile analytes. The system connects to standard gas chromatographs via a heated transfer line and is operated through the GERSTEL-MASter software or a handheld MAS Controller 505.

Key Results and Discussion

• Trap switching precision of 0.01 min enables collection of closely eluting compounds.
• Absence of valves and cold spots in the flow path ensures maximum transfer efficiency and minimal dead volume.
• Closed-split effluent flow divider allows simultaneous monitoring and trapping.
• Reliable operation over hundreds of injections underpins reproducible enrichment of trace substances.
• Example application illustrates isolation of thiazoline derivatives from yeast extract for further NMR characterization.

Benefits and Practical Applications

The GERSTEL PFC offers:

• High reproducibility in fraction collection for QA/QC and research laboratories.
• Enhanced sensitivity through trace enrichment across multiple injections.
• Efficient compound class grouping for streamlined sample preparation.
• User-friendly method development via manual or software control.

The system supports workflows in environmental analysis, flavor and fragrance research, and metabolomics where pure fractions are essential.

Used Instrumentation

• GERSTEL Preparative Fraction Collector (PFC) with six traps and one waste trap
• Gas chromatograph (any common GC) with heated transfer line
• GERSTEL-MASter software and MAS Controller 505
• Optional LN2 or cryostatic cooling unit

Future Trends and Potential Applications

Advancements may include integration with two-dimensional GC for enhanced resolution, development of novel trap materials to widen the analyte range, and AI-driven automation for real-time fraction optimization. Emerging fields like metabolomics and trace environmental monitoring will benefit from improved throughput and sensitivity.

Conclusion

The GERSTEL PFC is a versatile preparative fraction collector offering precise timing, high recovery, and robust performance. Its integration with GC/MS systems and flexible control options make it an invaluable tool for laboratories requiring pure fractions for advanced analytical techniques.