AQUATek 100 Waters-Only Autosampler

Importance of the topic

The analysis of volatile organic compounds in aqueous samples is essential for environmental monitoring, regulatory compliance and quality control in industries such as drinking water, wastewater, food and pharmaceuticals. Automated, closed-system purge and trap sample preparation minimizes analyte loss, ensures reproducibility and reduces labor intensive manual steps, thereby improving data quality and laboratory throughput.

Objectives and Study Overview

This application note presents the design, automation capabilities and performance of the AQUATek 100 Purge and Trap autosampler. The goals are to demonstrate compliance with USEPA methods for VOC analysis, to streamline sample handling via a vial-based closed-system technique and to illustrate the integration of self-diagnostics and software controls that enhance reliability and traceability.

Methodology and Instrumentation

The AQUATek 100 employs a fixed-volume PEEK™ sample loop that is filled by pressurizing the sample vial with inert gas. A two-stage robotic needle pierces the vial septum, displaces sample into the loop and then transfers the aliquot to a Purge & Trap Concentrator (Stratum PTC or Velocity XPT). A built-in clean-up cycle uses hot water rinse and gas purge to eliminate carryover. Optional on-board pH measurement confirms sample preservation without opening vials. The system supports closed-system vial cooling to 4 °C (with external recirculating bath), OptiRinse high-temperature pathway cleaning and automated blanking from a dedicated water reservoir.

Instrumentation Used

• AQUATek 100 Waters-Only Autosampler with 100-position VOA vial carousel and two-axis robotic arm
• Stratum Purge & Trap Concentrator or Velocity XPT Concentrator
• VOC TekLink 2G software on Windows® platform
• Optional pH probe module and recirculating cooling bath

Key Results and Discussion

Precision studies using a 5 mL loop delivered relative standard deviations below 1% (n=7). Standard and surrogate injections showed accuracy within ±0.1 µL and precision under 10% RSD. Closed-system vial handling and chilling preserved volatile organics, minimizing loss compared to open sampling. Integrated diagnostics such as leak tests, benchmark checks and real-time logging of pH and pressure ensured method robustness and simplified validation.

Benefits and Practical Applications

• Full automation of sample prep for drinking water, wastewater and industrial streams
• Compliance with multiple USEPA VOC methods (e.g., 502.1, 524.2, 503.0-series, 8260)
• Reduced labor, improved throughput and enhanced traceability via barcode tracking and audit trails
• Minimized carryover and loss through closed-system sampling and OptiRinse cleaning

Future Trends and Opportunities

Advances in autosampler integration with laboratory information management systems, predictive maintenance using AI-driven diagnostics and expansion to emerging contaminant assays will further streamline high-throughput VOC analysis. Miniaturized purge and trap modules and real-time remote monitoring are potential developments that can enhance field deployability and data transparency.

Conclusion

The AQUATek 100 Purge and Trap autosampler delivers reliable, compliant and fully automated sample preparation for aqueous VOC analysis. Its closed-system design, robust instrumentation and intuitive software combine to reduce analyte losses, enhance reproducibility and support a broad range of environmental and industrial applications.

References

• USEPA Method 5030: Purge and Trap for VOCs
• USEPA Methods 502.1, 502.2, 524.2–524.4, 503.1, 601–603, 624, 8010, 8015, 8020–8030, 8240, 8260