Formulae Differences Commence a Database for Interlaboratory Studies of Natural Organic Matter

Area of Science:

• Environmental science
• Analytical chemistry
• Biogeochemistry

Background:

• Direct comparison of high-resolution mass spectrometry (HRMS) data across different instruments or parameters is problematic.
• Inconsistencies arise from instrumental limitations and sample conditions, leading to distinct molecular species lists even for the same sample.
• Existing experimental data may not accurately reflect the original sample composition.

Purpose of the Study:

• To propose a novel method for classifying HRMS data that preserves the sample's essence.
• To develop a metric for comparing and classifying samples analyzed by different instruments.
• To establish a benchmark for future environmental and biogeochemical applications of HRMS data.

Main Methods:

• A new metric, formulae difference chains expected length (FDCEL), was developed.
• FDCEL classifies HRMS data based on element count differences between molecular formulae pairs.
• A web application and a prototype database for HRMS data were demonstrated.

Main Results:

• The FDCEL metric enables the comparison and classification of samples measured by different instruments.
• The method successfully preserves the essence of the given sample.
• FDCEL was effectively used for spectrum quality control and sample examination across various sample types.

Conclusions:

• The FDCEL metric offers a robust solution for standardizing HRMS data comparison.
• This approach enhances the reliability of HRMS data in biogeochemical and environmental studies.
• The developed tools and metric provide a foundation for a uniform HRMS data benchmark.