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Mass spectral reference libraries: an ever-expanding resource for chemical identification
1Chemical and Biochemical Reference Data Division, NIST, Gaithersburg, Maryland, United States. stephen.stein@nist.gov
Analytical Chemistry
|July 19, 2012
Summary
This study outlines compound identification using mass spectral libraries, detailing factors like prior probability and false result risks. It addresses challenges in spectral matching and the issue of unknown unknowns for improved confidence.
Area of Science:
- Analytical Chemistry
- Spectroscopy
Background:
- Compound identification is crucial in various scientific fields.
- Mass spectral reference libraries are widely used for this purpose.
Purpose of the Study:
- To present the fundamental principles, practices, and potential pitfalls in compound identification using mass spectral libraries.
- To discuss factors influencing identification confidence.
Main Methods:
- Review of established methodologies for mass spectral library searching.
- Analysis of key factors impacting the reliability of compound identification.
Main Results:
- Identification confidence is influenced by prior probability, false negative risk, and false positive risk.
- General concerns and the 'unknown unknowns' problem were explored.
Conclusions:
- Understanding these factors is essential for accurate compound identification.
- Addressing potential pitfalls enhances the reliability of mass spectral library searching.
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