Agilent ICP-MS Journal (August 2019. Issue 77)

Significance of the topic

ICP-MS techniques are essential for trace and ultra-trace elemental analysis in fields ranging from environmental monitoring and clinical diagnostics to materials science. Recent advances in triple quadrupole ICP-MS, laser ablation interfaces, reaction cell chemistry, and high-purity chemical standards significantly enhance sensitivity, interference removal, spatial resolution, and reproducibility, driving new applications and improving data quality.

Objectives and Study Overview

This issue presents multiple studies and developments aimed at optimizing ICP-MS performance and simplifying workflows:

• Review of factors affecting ICP-MS data quality
• High-resolution LA-ICP-QQQ imaging of gadolinium deposits in skin tissue
• Tools and strategies for rapid ICP-MS/MS method setup
• Expansion of Agilent’s inorganic chemical standards portfolio
• Comparison of Agilent and third-party ICP-MS interface cones

Methodology

Sample preparation, calibration, and analytical protocols varied by study:

• LA-ICP-QQQ imaging used 20 µm tissue sections of NSF skin and matrix-matched lamb brain standards spiked with defined elemental levels; liquid calibration employed H₂O₂/HNO₃ digestion and 7500cx introduction.
• ICP-MS/MS product ion scans guided selection of NH₃ cell gas modes by comparing Hf and REE reaction patterns over m/z 175–265.
• Interface cone performance was evaluated by measuring sensitivity, background, and stability on Agilent 7700 and 8900 ICP-MS systems across multiple analyte masses.

Instrumentation

• Agilent 8800 Triple Quadrupole ICP-MS
• Agilent 7700 and 7500cx Single Quadrupole ICP-MS
• Agilent 8900 Triple Quadrupole ICP-MS
• New Wave Research NWR193 Laser Ablation System

Main Results and Discussion

• LA-ICP-QQQ achieved a 16-fold lower LOD for phosphorus and 6-fold for gadolinium versus single quadrupole LA-ICP-MS, enabling 5 µm spot imaging of ~50 µm Gd/Ca/Zn phosphate plaques at >100 µg/g.
• ICP-MS/MS reaction mode leverages element-specific reactivity tables to select NH₃ gas for effective interference removal; MS/MS filtering ensured clean detection of 176HfN(NH₃)₄⁺ at m/z 258 free from 176Lu and 176Yb overlaps.
• Agilent’s new ULTRA Scientific standards portfolio offers over 1 000 high-purity, NIST-traceable CRMs and mixes in ISO Class 7 packaging, plus a custom-orders portal for tailored ICP-MS calibration and QC solutions.
• Cone comparison revealed that genuine Agilent sampling and skimmer cones deliver higher sensitivity, lower background, and superior short- and long-term stability than third-party cones, which showed weight deviations and performance variability.

Benefits and Practical Applications of the Method

• Enhanced spatial resolution and detection limits enable detailed mapping of Gd retention in fibrotic skin, advancing understanding of gadolinium deposition diseases.
• Predefined ICP-MS/MS method templates and reaction chemistry tools simplify development of robust methods for challenging matrices, reducing optimization time.
• High-quality standards and reliable interface cones improve routine laboratory QA/QC, lower maintenance requirements, and maintain consistent analytical performance.

Future Trends and Potential Applications

Emerging directions include broader adoption of triple quadrupole ICP-MS for environmental and clinical contaminant analysis, expansion of single-particle ICP-MS for nanoparticle characterization, development of comprehensive reaction-rate databases for MS/MS method design, greater automation of ICP-MS workflows, and generation of certified reference materials for novel sample types.

Conclusion

Collectively, these advances in instrumentation, methodology, and quality standards underscore the ongoing evolution of ICP-MS technology. By improving sensitivity, interference management, and workflow simplicity, they enable high-quality data across diverse applications and catalyze new research and industrial opportunities.

References

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2. FDA Drug Safety Communication, 2018, warns GBCAs are retained in the body
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4. D. J. Hare et al., Anal. Methods, 2013, 5, 1915–1921
5. J. Lear et al., Anal. Chem., 2012, 84, 6707–6714
6. T. Y. Lavrov et al., J. Phys. Chem. A, 2004, 108, 5610–5624