Mass-to-Charge Ratio Set Matching: A Novel and Efficient Compound Identification Method

Background: GC-MS is a powerful tool for component analysis of unknown compounds, especially in the fields of analytical chemistry and detection of biological samples. To effectively identify compounds in GC-MS, one of the most important ways is to use a matching algorithm to compare the similarity between the reference spectrum and the query spectrum. 

Objective: To propose a novel way to improve compound identification accuracy. 

Methods: This article proposes a method based on an m/z set match. First of all, select the maximum m/z and the m/z corresponding to the highest peak intensity in a pre-search. Next, employ the space vector model to carry on a refined search in the remaining spectra after the pre-search. Then, distinguish stereoisomers according to the order of the G value. 

Results: Compared with the 10 peaks and the method based on an m/z number matching pre-search, the method based on m/z set matching showed higher accuracy and fewer remaining (missing) spectra. Furthermore, the refined search which is based on the m/z set matching method possesses shorter calculation time compared with no pre-search.

Conclusions: The method can reduce the remaining spectra and speed up the identification of compounds.