Agilent 8900 Triple Quadrupole ICP-MS (Technical Overview)

Significance of the Topic

Triple quadrupole inductively coupled plasma mass spectrometry (ICP-QQQ) represents a transformative advancement in elemental analysis. By integrating two mass filters with a reaction cell, ICP-QQQ overcomes limitations of single quadrupole ICP-MS, delivering unmatched interference control, ultra-trace detection limits, and consistent reaction chemistry. These capabilities are critical for applications in semiconductor manufacturing, high-purity materials testing, environmental monitoring, food safety, life sciences, and nanoparticle characterization.

Objectives and Study Overview

The presented work reviews the evolution from Agilent’s first ICP-QQQ model (8800) to the enhanced 8900 instrument. Key objectives include:

• Improving sensitivity and background reduction for challenging analytes (e.g., Si, S, P).
• Extending matrix tolerance for high-salt or complex samples.
• Expanding functionality for single nanoparticle (spICP-MS) analysis.
• Enhancing productivity through simplified workflows and robust hardware.

Methodology and Instrumentation

ICP-QQQ employs an MS/MS configuration: Q1 filters precursor ions, an octopole reaction cell (ORS4) conducts controlled chemistry with reactive or collision gases, and Q2 performs final mass selection. This tandem arrangement ensures predictable ion–molecule reactions, eliminates off-target interferences, and enables on-mass and mass-shift modes.

Instrumentation Used

The Agilent 8900 ICP-QQQ features:

• High-frequency hyperbolic quadrupoles (Q1 and Q2) for unit mass resolution.
• Fourth-generation ORS4 with axial acceleration for enhanced reaction product transmission.
• Advanced vacuum interface and optimized extraction lens (x-lens, s-lens, or m-lens) for up to two-fold sensitivity improvement.
• Ultra-high matrix introduction (UHMI) to tolerate up to 25% total dissolved solids.
• Fast time-resolved analysis (TRA) detector with 0.1 ms dwell time and up to 11 orders of magnitude dynamic range.
• Modular configurations: Standard, Advanced Applications, and Semiconductor, tailored for specific performance needs.

Main Results and Discussion

Key performance achievements of the 8900 include:

• Detection limits of 1–2 ppq for Th and U, driven by high sensitivity (>700 Mcps/ppm Y) and <0.2 cps background.
• Mass-shift MS/MS detection limits of 15 ppt for Si (using H2) and 5 ppt for S (using O2) after replacing instrument components with inert materials.
• Enhanced interference removal demonstrated in selenium analysis: Q1 rejects non-target masses, ORS4 transforms Se+ to SeO+, and Q2 isolates the product ion free of isobaric overlaps.
• UHMI performance matching single quadrupole robustness, enabling direct analysis of high-matrix samples without dilution.
• Single nanoparticle ICP-MS capability for SiO2 and TiO2 NPs down to 50 nm, with background equivalent diameters <25 nm, supported by fast TRA acquisition.

Benefits and Practical Applications

ICP-QQQ unlocks new analytical possibilities:

• Ultra-trace elemental analysis in semiconductor process chemicals and high-purity water.
• Reliable measurement of traditionally challenging elements (Si, S, P, Cl, F) at ppt–ppq levels.
• Robust quality control in food, environmental, and pharmaceutical laboratories using IntelliQuant and automated QA/QC.
• Accurate nanoparticle size distribution and concentration for environmental fate studies and product safety assessment.

Future Trends and Potential Applications

Emerging directions include:

• Integration of machine learning for automated method optimization and interference prediction.
• Development of novel reaction gases and dynamic cell control for expanded element coverage.
• Coupling with microfluidic sample preparation and automation for high-throughput screening.
• Advanced isotopic ratio measurements for nuclear forensics and geochronology.
• Expanded use in metallomics, clinical diagnostics, and in situ environmental monitoring.

Conclusion

The Agilent 8900 ICP-QQQ builds on the pioneering 8800 platform to deliver enhanced sensitivity, ultra-low backgrounds, superior interference control, and single-particle analysis. Its modular design and robust MS/MS architecture make it a versatile tool for diverse analytical challenges, from routine high-matrix samples to cutting-edge nanoparticle and ultra-trace studies.

Reference

1. Agilent Technologies. Handbook of ICP-QQQ Applications using the Agilent 8800 and 8900, 5th Edition, 2022, publication number 5991-2802EN.
2. Balcaen L, Bolea-Fernandez E, Resano M, Vanhaecke F. Anal Chim Acta. 2015;894:7–19.
3. Jackson BP, Liba A, Nelson J. J Anal At Spectrom. 2015;30:1179–1183.
4. Nakano K. Agilent application note, 2016; publication number 5991-6852EN.
5. Nunez S, Goenaga Infante H, Yamanaka M, Itagaki T. Agilent application note, 2016; publication number 5991-6944EN.
6. Yamanaka M, Itagaki T, Wilbur S. Agilent application note, 2016; publication number 5991-6596EN.