High Throughput Water Analysis using Agilent 7900 ICP-MS coupled with ESI prepFAST

Importance of the Topic

This summary highlights the significance of high-throughput automated elemental analysis of water samples in environmental, regulatory, and quality control laboratories. Coupling inductively coupled plasma mass spectrometry with a syringe-based autodilution system addresses the need for rapid, accurate, and contamination-minimized workflows.

Study Objectives and Overview

The study evaluated an integrated analytical platform consisting of an Agilent 7900 ICP-MS coupled to the ESI prepFAST M5 autodilution system, operated through Agilent MassHunter software. The goals were to streamline calibration, detect over-range and out-of-range conditions, and verify compliance with EPA Method 200.8 across various water matrices including tap, bottled, and certified reference materials.

Methodology and Instrumentation

The workflow combined discrete sample introduction and automated dilution within a single sequence. Key features and conditions included:

• Automated prepFAST M5 autodilution of calibration standards and samples based on user-defined criteria
• Sample set: three tap waters, seven bottled waters, and NIST SRM 1643f at undiluted and 2x dilution
• Acid matrix: 2% HNO3 with 1% HCl to stabilize target elements
• 29 analytes calibrated across seven automatic dilution levels; internal standards 72Ge, 89Y, 103Rh, and 175Lu at 20 ppb
• Instrumentation: Agilent 7900 ICP-MS with PFA-ST nebulizer, general-purpose plasma mode, and He collision mode for interference reduction

Key Results and Discussion

Calibration curves demonstrated excellent linearity for trace elements including V, As, Cd, and Hg, with detection limits as low as 0.01 ppb. Method detection limits for 29 elements met or exceeded EPA 200.8 requirements. Intelligent autodilution corrected over-range analytes and internal standard anomalies in real time. NIST SRM recovery tests (n=20) showed ±10% accuracy for most certified elements, while ongoing CCV blanks maintained ±10% control limits over extended sequences.

Benefits and Practical Applications

The integrated system offers:

• Reduced hands-on time and manual dilution steps
• Minimized contamination risk and reanalysis rate
• Enhanced throughput of approximately two minutes per sample
• Seamless quality control including calibration, CCV, CCB, and ISTD checks
• Regulatory compliance with minimal user intervention

Future Trends and Potential Applications

Advancements may include application to diverse sample types beyond water, integration with laboratory information management systems, AI-driven QC and method optimization, and further miniaturization of sample preparation modules to enhance throughput and flexibility.

Conclusion

Integrating the 7900 ICP-MS with the ESI prepFAST M5 autodilution system under MassHunter control delivers a robust, automated solution for routine elemental water analysis. It enhances data quality, operational efficiency, and regulatory compliance, while simplifying laboratory workflows.

References

1. Schultz A and Field P. prepFAST ICP-MS: Environmental, Elemental Scientific Inc., 2017.
2. U.S. EPA Method 200.8 Revision 5.4. Determination of Trace Elements in Waters and Wastes by ICP-MS, 1994.
3. Sakai T and McCurdy E. Agilent 7900 ICP-MS simplifies drinking water analysis, Agilent Technologies Application Note, 2014.