Fast Analysis of Environmental Samples using an Agilent ICP-OES and an ESI prepFAST autodilutor

Importance of the Topic

Monitoring treated municipal wastewater, stormwater runoff, and industrial effluents is essential to ensure discharge compliance with environmental regulations. The efficient, accurate, and high-throughput determination of trace and major elements in complex aqueous and solid matrices is critical for protecting ecosystems and public health. Implementing robust, automated methods minimizes manual handling, reduces errors, and accelerates decision-making in regulated laboratories.

Objectives and Study Overview

This study demonstrates an automated workflow for environmental sample analysis fully compliant with US EPA Method 200.7. The goals were to integrate an Agilent 5110 Synchronous Vertical Dual View (SVDV) ICP-OES with an ESI prepFAST 2 autodilution system, validate performance with certified reference materials (CRMs), and evaluate key metrics including linear dynamic range, matrix tolerance, detection limits, and long-term stability.

Methodology and Instrumentation

The heart of the system is the Agilent 5110 SVDV ICP-OES, equipped with Dichroic Spectral Combiner technology for simultaneous axial and radial emission capture, a vertical torch for robust plasma, and a solid-state RF generator. Samples and standards are handled by the ESI prepFAST 2 autodilutor coupled to an SC-DX autosampler. Key components include:

• Double-pass glass cyclonic spray chamber and PFA-ST nebulizer
• Easy-fit 1.8 mm injector torch
• Integrated syringe pumps for precise inline mixing of samples, diluents, and internal standard
• ICP Expert software controlling automated calibration, autodilution, and QC procedures

Calibration standards originate from a single multi-element stock and are prepared inline at dilutions ranging from 1× to 200×. A yttrium internal standard is added automatically. Spectral interferences are managed through stored interelement correction factors and advanced real-time techniques (FACT and FBC), exploiting continuous CCD wavelength coverage.

Main Results and Discussion

• Calibration linearity (r2 ≥ 0.9995) was achieved across all elements using inline-diluted standards.
• The automated dilution extended the effective linear dynamic range well above the highest calibration point, correcting self-absorption effects for elements such as iron.
• High-matrix samples (digested soil, river sediment) yielded accurate recoveries (85–105 %) across dilutions up to 100×.
• Prescriptive and intelligent autodilution addressed out-of-range analytes and internal standard failures without analyst intervention, restoring accurate results.
• Continuing calibration verification over 6.75 hours (measured every ten samples) remained within ±10 % recovery (RSD < 1.5 % for most elements).
• Method detection limits met EPA requirements, with MDLs ranging from 0.17 µg/L (Li) to 27 µg/L (K).

Benefits and Practical Applications

The combined ICP-OES and prepFAST platform offers:

• Fully automated multilevel calibration and sample dilution, reducing manual pipetting and documentation.
• Automated response to QC breaches—samples out of calibration or ISTD limits are diluted and re-measured without user input.
• Significant reduction in chemical waste and consumable usage, as only required volumes are prepared inline.
• Enhanced sample throughput through rapid vacuum loading, reduced uptake/wash delays, and minimized reruns.
• Robust performance with complex matrices, lowering the risk of plasma instability and spectral interferences.

This workflow is well suited for environmental testing laboratories engaged in wastewater, sludge, soil, and sediment analysis under regulatory frameworks.

Future Trends and Possibilities

Looking ahead, further integration with laboratory information management systems (LIMS) and cloud-based data analytics will streamline reporting and compliance. Advances in machine learning–driven spectral correction could enhance interference management. Miniaturized or portable ICP-OES systems with onboard autodilution may open field-deployable environmental monitoring. Green chemistry initiatives will drive reductions in reagent volumes and energy consumption.

Conclusion

The Agilent 5110 SVDV ICP-OES combined with the ESI prepFAST 2 autodilution system delivers a high-throughput, fully automated solution for environmental elemental analysis under EPA Method 200.7. The platform’s robust calibration, intelligent autodilution, and advanced spectral correction techniques enable accurate, precise, and efficient measurement of over 30 elements in complex matrices, while minimizing waste and manual intervention.

Reference

1. US EPA Method 200.7: Trace Elements in Water, Solids, and Biosolids by ICP-AES, Rev. 5.0, 2001
2. Agilent Synchronous Vertical Dual View (SVDV) for 5110 ICP-OES, 2016
3. Ultra-fast ICP-OES Determination of Trace Elements per US EPA 200.7, 2017
4. FACT Spectral Deconvolution Software, Agilent, 2016
5. Fitted Background Correction (FBC) for ICP-OES, Agilent, 2014