CDS 7000C PAL System Purge and Trap Plugin

Importance of the Topic

Volatile organic compound analysis via purge and trap coupled to gas chromatography remains a cornerstone technique in environmental monitoring, industrial hygiene, and quality control. It provides sensitive, reproducible extraction and concentration of trace-level analytes from aqueous or gaseous matrices, ensuring regulatory compliance and reliable data for research and diagnostic laboratories.

Objectives and Overview of the Study

This document presents the CDS 7000C PAL System Purge and Trap Plugin, the first in-line purge and trap concentrator designed specifically for integration with the CTC Combi PAL autosampler. The primary goal is to deliver automated, high-performance sample introduction for a wide range of volatile organic compounds with minimal user intervention.

Methodology and Instrumentation

The system combines established purge and trap technology with modern automation features:

• Purge and trap concentrator module that seamlessly attaches to PAL autosampler platforms
• Industry-standard foam sensor for real-time gas flow monitoring
• Redesigned wet trap compartment to eliminate moisture interference
• Exchangeable pneumatic cartridge for rapid maintenance
• Stainless steel-clad fused silica transfer line, heated to 350 °C, ensures efficient analyte movement
• Adsorbent trap options include Vocarb or Tenax materials, operable to 300 °C
• Programmable purge times up to 999.9 minutes and desorb preheat functionality
• Optional modules: hot water rinse, heated sparge vessel, internal standard addition, electronic mass flow control, leak check pressure transducer

Main Results and Discussion

Performance evaluations demonstrate detection of 61 volatile analytes at 20 ppb in water with clear chromatographic resolution. Multiple injections of six representative gases at 500 ppt show excellent reproducibility. Linearity tests for vinyl chloride from 500 ppt to 50 ppb confirm stable response across three orders of magnitude. These data underline the system’s capability for trace-level quantitation and robustness against moisture and matrix effects.

Benefits and Practical Applications

The CDS 7000C PAL Plugin offers:

• Fully automated sample introduction for high throughput laboratories
• Enhanced moisture management via the wet trap design
• Rapid trap exchange and low downtime with plug-and-play pneumatics
• Wide dynamic range and low detection limits suitable for environmental, food safety, and petrochemical analysis

Future Trends and Possibilities

Emerging directions include integration with advanced detectors such as time-of-flight mass spectrometers, development of new sorbent materials for broader analyte coverage, and smarter software algorithms for adaptive purge conditions. Further miniaturization of modules and remote monitoring capabilities will enhance field deployability and real-time decision making.

Conclusion

The CDS 7000C PAL System Purge and Trap Plugin represents an important advance in automated volatile analyte purification and concentration. Its modular design, high sensitivity, and compatibility with leading autosampler platforms make it a versatile choice for laboratories seeking reliable, high-throughput volatile analysis.

Reference

CDS Analytical LLC. CDS 7000C PAL System Purge and Trap Plugin, GN-21, November 2016.