AQUATek 100 Waters-Only Autosampler

Significance of the Topic

The analysis of volatile organic compounds (VOCs) in aqueous samples is critical for environmental monitoring, regulatory compliance, and quality control in industries such as water treatment, food and beverage, pharmaceuticals, and petrochemicals. Automated sample preparation using purge and trap technology enhances accuracy, reproducibility, and throughput while minimizing analyte loss and operator exposure.

Objectives and Study Overview

This document presents an overview of the AQUATek 100 Purge and Trap Autosampler designed to fully automate liquid sample preparation for VOC analysis. Key goals include seamless integration with concentrators, closed‐system sampling to preserve volatile analytes, and compliance with USEPA standardized methods. Emphasis is placed on operational simplicity, reliability, and data integrity.

Methodology and Used Instrumentation

The AQUATek 100 operates by pressurizing sealed vials to fill a fixed‐volume PEEK sample loop. Internal standards or surrogates are automatically added, and the sample is transferred to a connected purge and trap concentrator (e.g., Stratum PTC or Velocity XPT). After analysis, an automated clean‐up sequence uses heated blank water (OptiRinse) and inert gas purge to prepare the system for the next sample. Key optional modules include:

• On‐board pH probe for sample preservation verification
• External recirculating cooling bath to maintain sample tray at 4 °C

Software control is managed by VOC TekLink™ 2G, offering schedule creation, method editing, real‐time diagnostics (leak and benchmark tests), audit trail capabilities, and customized alerting.

Main Performance Parameters and Discussion

Precision and accuracy benchmarks demonstrate robust performance:

• Sample delivery precision: <1% RSD at 5 mL volume (n=7)
• Standard injection precision: <10% RSD (5 µL on GC/FID for model compounds)
• Standard addition accuracy: ±0.1 µL for 1 µL injections

The closed‐system sampling technique and vial chiller minimize analyte loss and sample matrix alteration, ensuring reliable quantification of low‐level VOCs. Automated leak checks and electromechanical benchmark tests enhance instrument uptime and regulatory compliance.

Benefits and Practical Applications

Automating purge and trap sample preparation with the AQUATek 100 yields multiple advantages:

• Enhanced throughput with 100‐position vial carousel and optiRinse cleaning
• Reduced labor costs and human error via robotic vial handling and closed‐system transfers
• Full compliance with USEPA Methods 5030, 502.x, 524.x, 601–603, 624, 8010–8030, 8240, and 8260
• Data integrity through integrated pH monitoring, pressure logging, and audit trails

Typical applications include drinking water analysis, wastewater monitoring, trace VOC screening in food and beverage matrices, and pharmaceutical quality control.

Future Trends and Possibilities

Advances likely to shape next‐generation autosamplers include:

• Integration with laboratory information management systems (LIMS) and cloud‐based data platforms
• Enhanced sensor arrays for multi‐parameter sample characterization (e.g., conductivity, turbidity)
• Miniaturized modules for on‐site or field‐deployable VOC analysis
• Machine learning–driven predictive maintenance and method optimization

Conclusion

The AQUATek 100 provides a comprehensive, automated solution for purge and trap preparation of VOC samples in diverse liquid matrices. Its combination of closed‐system sampling, robust instrument diagnostics, and software integration ensures high accuracy, regulatory compliance, and operational efficiency, making it a valuable tool for analytical laboratories.