Cooled Injection System - CIS 4 - Specifications

Importance of the Topic

Cooled injection systems enhance gas chromatographic analysis by trapping volatile and thermally labile compounds at low temperatures, improving sensitivity and peak resolution. Precise temperature control during sample introduction minimizes discrimination and matrix effects, making these systems essential for trace analysis in environmental, food, and forensic applications.

Objectives and Overview

This summary presents the design, performance specifications, and practical capabilities of the CIS 4 cooled injection system. The focus is on its integration with Agilent GC platforms, cooling options, temperature programming range, injection modes, and automation features.

Methodology

The CIS 4 employs a programmable temperature vaporizing (PTV) inlet combined with advanced cooling modules. It supports multiple cooling techniques to achieve a broad temperature range and versatile injection workflows.

Used Instrumentation

• Programmable temperature vaporizing inlet (CIS 4) compatible with Agilent 6850, 6890, and 7890 GC instruments
• Controller C506 integrated with GERSTEL MAESTRO or Agilent ChemStation software
• Cooling modules: liquid nitrogen (–150 to –180 °C), liquid CO₂ (–70 °C), cryostatic (–40 °C), and Peltier (up to +10 °C)
• GERSTEL MPS 2 autosampler with ALEX option for automated liner exchange

Main Findings and Discussion

Key performance features include:

• Wide temperature range from –150 °C to +450 °C, programmable in up to two ramps with rates up to 16 °C/s
• Multiple injection modes: split/splitless, solvent venting, on-column, large-volume, and cryo-trapping
• High-pressure and high-flow capabilities (0–100 psi; He/H₂ up to 1000 mL/min)
• Seamless integration allows a single method file for GC/MS workflows and graphical temperature program setup

The system’s modular design and robust sealing ensure reliable performance under varying sample matrices and operating conditions.

Benefits and Practical Applications

The CIS 4 offers:

• Enhanced sensitivity for trace compounds through cryogenic trapping and large volume injections
• Reduced sample discrimination and improved reproducibility via precise temperature control
• Streamlined workflows with automated liner exchange and compatibility with standard autosamplers
• Flexibility to handle diverse sample types in environmental monitoring, food safety, petrochemicals, and forensic analysis

Future Trends and Potential Applications

Advancements may include integration with real-time data analytics, miniaturized cooling modules for field-deployable GC systems, and expanded automation for high-throughput laboratories. Emerging materials for inert liners and dynamic cooling strategies will further improve system performance and sustainability.

Conclusion

The CIS 4 cooled injection system provides a versatile and robust solution for modern gas chromatography, delivering precise temperature control, multiple injection modes, and seamless automation. Its broad applicability and integration capabilities make it a valuable tool for laboratories demanding high sensitivity and reproducibility.