Comparison of sequential derivatization with concurrent methods for GC/MS-based metabolomics

• Published in: Journal of bioscience and bioengineering Vol. 127; no. 2; pp. 160 - 168
• Main Authors: Miyagawa, Hiromi, Bamba, Takeshi
• Format: Journal Article
• Language: English
• Published: Japan Elsevier B.V 01-02-2019
• Subjects: Catalysis; Derivatization; Gas Chromatography-Mass Spectrometry - methods; Gas chromatography/mass spectrometry; Hydroxylamines - chemistry; Hydroxylamines - metabolism; Indicators and Reagents; Metabolome; Metabolomics; Metabolomics - methods; Methoximation; Trimethylsilyl Compounds - chemistry; Trimethylsilyl Compounds - metabolism; Trimethylsilylation; Metabolome; Metabolomics; Trimethylsilylation; Derivatization; Gas chromatography/mass spectrometry; Methoximation
• ISSN: 1389-1723; 1347-4421
• DOI: 10.1016/j.jbiosc.2018.07.015

The gas chromatography/mass spectrometry (GC/MS)-based metabolomics requires a two-step derivatization procedure consisting of oximation and silylation. However, due to the incomplete derivatization and degeneration of the metabolites, good repeatability is difficult to obtain during the batch derivatization, as the time between completing the derivatization process and GC analysis differs from sample to sample. In this research, we successfully obtained good repeatability for the peak areas of 52 selected metabolites by sequential derivatization and interval injection, in which the oximation and silylation times were maintained at constant values. In addition, the derivatization times and amount of reagents employed were varied to confirm that the optimal derivatization conditions differed for the various metabolites. In conventional batch derivatization, six metabolites, viz. glutamine, glutamic acid, histidine, alanine, asparagine, and tryptophan, exhibited fluctuations in their peak areas. Indeed, we found that for all six metabolites these differences originated from the silylation process, while the variations for glutamine and glutamic acid were related to the oximation process.
•Analytical method is developed using sequential derivatization and interval GC injection.•Sequential and batch derivatization are compared using a mixture of the 52 metabolites.•Derivatization times and amount of derivatization reagents are investigated.•In conventional batch derivatization, 6 metabolites exhibited fluctuations in their peak areas.