Multi-Isotope Internal Standardization for Inductively Coupled Plasma Mass Spectrometry

Area of Science:

• Analytical Chemistry
• Spectrometry

Background:

• Traditional trace analyte determination relies on single signal-to-concentration relationships.
• Existing multisignal methods face limitations like low throughput, poor accuracy in complex matrices, and requirement for multiple signals per analyte.

Purpose of the Study:

• To introduce and evaluate Multi-Isotope Internal Standardization (MIIS) as an advanced calibration method for ICP-MS.
• To address limitations of existing multisignal techniques in trace analyte determination.

Main Methods:

• Developed a novel calibration method, MIIS, utilizing multiple isotope masses for analytes and internal standards.
• Employed only two calibration solutions for constructing the calibration curve.
• Validated MIIS through spike recovery experiments in complex matrices and analysis of certified reference materials.

Main Results:

• MIIS achieved approximately 100% analyte recovery with low relative standard deviations (few percent) in challenging sample matrices.
• Demonstrated superior performance compared to traditional calibration and other multisignal methods.
• Validation in certified reference materials showed recoveries ranging from 85% to 111%.

Conclusions:

• MIIS offers a significant advancement in ICP-MS calibration for trace analyte determination.
• The method provides a high number of calibration points with minimal solution preparation.
• MIIS overcomes limitations of previous techniques, enhancing accuracy and efficiency.