Agilent ICP-MS Journal (June 2007 – Issue 31)

Importance of the Topic

The set of articles from the June 2007 ICP-MS Journal illustrates critical developments in inductively coupled plasma mass spectrometry (ICP-MS) for clinical and environmental analysis. They highlight methods to improve throughput, accuracy, and interference management in trace metal determination, showcasing applications in biomedical and water testing, and introducing novel tuning and collision cell technologies that streamline laboratory workflows.

Objectives and Overview

The issue comprises four main contributions:

• A user success story on rapid determination of aluminum and zinc in end-stage renal disease patient plasma.
• Details of new pulse/analog (P/A) tuning and calibration solution kits for the Agilent 7500 Series ICP-MS.
• A summary of Agilent’s global leadership in the ICP-MS market.
• Performance evaluation of the Agilent 7500cx in helium collision mode and its application to interference-free semiquantitative screening.

Methodology and Instrumentation

Sample preparation and instrument configuration were central to all studies:

• Satellite Laboratory Services replaced GFAA with two Agilent 7500 ICP-MS instruments, using a single 1:20 dilution for simultaneous Al and Zn measurement in plasma, equipped with a CETAC ASX-520 autosampler.
• Agilent 7500 Series P/A Tuning Solution Kit (part #5188-6524) provides multi-element mixtures across the mass range for one-step autotune; internal standard mix (part #5188-6525) and EPA 6020 compliant interference check solutions (parts #5188-6526 and #5188-6527) support method setup and QA/QC.
• The 7500cx was tuned at 1550 W, with He collision gas at 5 mL/min, enabling kinetic energy discrimination to remove polyatomic interferences under a single universal tune; optional H2 or Xe cell gases extend detection for challenging elements.

Key Results and Discussion

Determination of Aluminum and Zinc in Plasma

• Calibration linear from 0.05 to 300 ppb for both Al and Zn.
• Routine acceptance criteria achieved: r2≥0.999, BEC≤0.3 ppb, ISTD RSD≤10 %, with automated check controls every 20 samples.
• Turnaround times reduced from 1–2 weeks (GFAA) to 1–3 days with the 7500a; third instrument validated for water analysis.

Performance Characteristics of the 7500cx

• Sub-ppb IDLs across most elements in He mode (e.g., Be <10 ppt, Se ~150 ppt).
• Interference removal for Se, As, V demonstrated in high-matrix samples, with background equivalent concentrations <200 ppt.
• Long-term stability over 300 samples in 12 hours, including 48 replicates of NIST 1640, maintained recoveries within 90–110 %.

Interference-Free Semiquantitative Analysis

• Universal He collision tune enabled accurate semiquant screening of NIST 1640, LGC 6010 drinking water and LGC 6177 leachate, with certified analytes recovered within ±30 %.
• Full mass range acquisition in <3 minutes per sample without mode changes or interference corrections.

Benefits and Practical Applications

The integrated developments deliver:

• Reduced sample preparation and simplified workflows with single dilutions and universal tuning.
• Higher throughput and faster turnaround in clinical and environmental laboratories.
• Robust interference suppression for complex matrices without multiple mode optimizations.
• Reliable semiquantitative screening for rapid assessment of unknown samples.

Future Trends and Opportunities

Advances in collision/reaction cell design and novel gas chemistries will further lower detection limits and expand analyte scope. Automated tuning solutions and enhanced calibration kits will reduce setup times, while integration with hyphenated techniques (LC–ICP-MS) and on-line sample preparation promise to meet growing demands in bioanalysis, speciation studies, and high-throughput environmental monitoring.

Conclusion

The Agilent 7500 Series, especially the 7500cx with helium collision mode, represents a comprehensive solution for modern trace element analysis. By combining universal tuning, efficient interference removal, and rapid semiquantitative screening, laboratories achieve greater productivity, accuracy, and flexibility across clinical and environmental applications.

References

• Application note 5989-6663EN: Performance Characteristics of the Agilent 7500cx ICP-MS.
• Application note 5989-6662EN: Faster, Simpler, More Accurate Semiquantitative Analysis using the Agilent 7500cx.