Effects of Deproteinization and Derivatization in Serum Preparation on Serum Metabolome Based on Gas Chromatography-Mass Spectrometry

The effects of different deproteinization and derivatization methods in serum sample preparation on metabolome were compared by gas chromatography-mass spectrometry. The relative standard derivations (RSD) of peak area and information content of profile were calculated. The principal components analysis (PCA), qualitative and quantitative analysis of serum samples and quality control samples (QC) were done. The RSD of QC and serum samples was less than 10%. The result of information content and PCA showed that these serum preparation methods were stable and reliable. The PCA result of profile produced by four preparation methods showed that the differences existed in serum metabolome when the samples were deproteinized and derivatizated by different reagents in preparation procedures. The influence of derivatization reagents on serum metabolome was great than that of deproteinization reagents. The information content of samples derivatizated by N-methyl-N-(trimethylsilyl) trifluoroacetamide (MSTFA) (8. 9) was higher than that of samples derivatizated by BSTFA (8. 7). Forty-four metabolites were obtained by qualitative analysis. Five metabolites were unique to samples derivatizated by MSTFA, and six metabolites were unique to samples derivatizated by N, O-Bis(trimethylsilyl) trifluoroacetamide (BSTFA). We proposed that when polar amino acids and short-chain fatty acids were concerned, BSTFA was recommended as derivatization reagent, and when nonpolar amino acids and long. chain fatty acids were concerned, MSTFA was recommended as derivatization reagent.