Table 1.

Identification parameters for common setups in metabolomics research.

Processing Step	GC-EI–ToF-MS	LC–Orbitrap-MS
Derivatisation	essential to mask polar groups	not essential but can be used selectively to target specific compound classes
Chromatographic resolution	narrower peaks (ca. 4–5 s)	wider peaks (ca. 20–30 s)
MS-resolution	typically unit-resolution	high resolution
Chromatographic identification	typically by retention index system	typically reliant on retention time
Compound identification	based on fragmentation	based on (exact) mass
Potential misident- ifications	metabolites with chemical similarity	metabolites with identical sum formula