Agilent ICP-MS Journal (September 2009 – Issue 39)

Significance of the Topic

The introduction of the Agilent 7700 Series ICP-MS represents a major advance in quadrupole ICP-MS design, directly addressing longstanding challenges in matrix tolerance, dynamic range and spectral interference removal. By combining a fast frequency-matching RF generator, a high-performance ion lens, the third-generation Octopole Reaction System (ORS3) and an integrated High-Matrix Introduction (HMI) interface, the 7700 Series delivers more accurate, robust and productive trace and major element analyses across a wide variety of sample types.

Objectives and Study Overview

This collection of technical reports aimed to:

• Describe the design features and key performance specifications of the new Agilent 7700 Series (7700x and 7700s).
• Demonstrate the enhanced interference removal capabilities of the ORS3 in helium collision mode for complex matrices.
• Evaluate the instrument’s analytical performance in routine applications, including drinking water and food sample analysis.
• Highlight the practical benefits of a universal, single-gas collision-cell method and streamlined software workflows.

Methodology and Instrumentation

The 7700 Series incorporates multiple innovations to achieve its performance gains:

• Fast, frequency-matching 27 MHz RF generator tolerant of high organic loads.
• Peltier-cooled spray chamber and low-flow sample introduction for improved stability.
• Redesigned off-axis ion lens delivering higher sensitivity and lower background.
• High-Matrix Introduction (HMI) system for direct analysis of samples up to several percent total dissolved solids.
• Third-generation Octopole Reaction System (ORS3) optimized for helium collision mode using kinetic energy discrimination.
• High-transmission, matrix-tolerant interface and high-performance vacuum system.
• Hyperbolic quadrupole mass analyzer coupled to a simultaneous dual-mode detector covering nine orders of dynamic range.
• Agilent MassHunter Software with One-click Plasma Setting, automated tuning and comprehensive data reporting.

Key Results and Discussion

Interference Removal in Complex Matrices
The ORS3 performance was tested using a mixed acid/organic matrix known to generate multiple polyatomic overlaps. No-gas and H2 reaction modes left significant residual interferences and created new overlaps, whereas helium mode with ORS3 achieved complete removal of matrix-derived polyatomics without introducing artefacts.

Drinking Water Analysis
In a continuous 11-hour sequence of 190 samples including high-TDS mineral waters and EPA-required calibration checks, no continuing calibration verification failures occurred. Method detection limits ranged from sub-ppt levels (e.g., Hg 1.2 ppt, U 1.7 ppt) to low tens of ppt for first-row transition metals, and robust plasma settings were maintained via One-click Plasma Setting.

Food Sample Screening
Certified reference materials (fish protein, mussel tissue, whole egg powder) were digested by microwave and analyzed in a single helium cell-gas run. Results for trace metals (As, Se, Cd, Pb, etc.) agreed within certified uncertainties, demonstrating that the 7700x can replace multiple dedicated techniques (ICP-OES, GFAAS, CV-AAS) for rapid total metal screening.

Benefits and Practical Applications

The 7700 Series offers the following advantages for routine and research laboratories:

• Universal interference removal under a single helium collision-cell mode eliminates method complexity and sample-specific corrections.
• Broad dynamic range (sub-ppt to >500 ppm) in a single acquisition simplifies quantitation across diverse analyte concentrations.
• High matrix tolerance extends analysis to challenging sample types without dilution or alternative techniques.
• Automated plasma optimization and tuning reduces setup time and operator variability.
• Compact footprint and reduced weight (30% smaller than the previous generation) save laboratory space.

Future Trends and Potential Applications

Upcoming developments and application areas include:

• Integration with hyphenated techniques (LC-ICP-MS, GC-ICP-MS) for speciation analysis of elements such as As, Se and Hg.
• Exploration of alternative cell gases and reaction chemistries for targeted removal of challenging interferences.
• Increased automation and remote monitoring capabilities for high-throughput and regulated environments.
• Application to emerging fields such as nanoparticle characterization, bioimaging and metallomics.
• Enhanced data analytics and cloud-based processing for improved laboratory informatics.

Conclusion

The Agilent 7700 Series achieves the long-promised performance of quadrupole ICP-MS by uniting innovative hardware and software advances. Its universal helium collision-cell method, extensive dynamic range and high matrix tolerance simplify method development, improve data quality and boost laboratory productivity across environmental, food, semiconductor and research applications.

References

• Agilent Technologies. The Agilent 7700 Series ICP-MS: Extraordinary Design. Unparalleled Performance. Brochure, 5990-4025EN.
• Agilent Technologies. The Agilent 7700 Advantage for Drinking Water Analysis. Application Note, 5990-4315EN.
• Agilent Technologies. Simple, Rapid Analysis of Trace Metals in Foods Using the Agilent 7700x ICP-MS. Application Note, 5990-4539EN.
• Agilent Technologies. Comparing Collision/Reaction Cell Modes for the Measurement of Interfered Analytes in Complex Matrices using the Agilent 7700 Series ICP-MS. Technical Overview, 5990-3236EN.
• Agilent Technologies. Agilent 7700 Series ICP-MS – Design, Technology and Principles of Operation. Wall Poster, 5990-4234EN.