Sample Preparation in Global Metabolomics of Biological Fluids and Tissues - Proteomic and Metabolomic Approaches to Biomarker Discovery - page 58

FIGURE 4 Comparison of reproducible features shared in common between metabolite extraction methods, after hierarchical
clustering. The length of the vertical lines is a measure of similarity, with shorter lines demonstrating more common features.
The diagonal shaded boxes contain the total number of reproducible features for each method, de

ned as a feature that was

detected in at least five out of six LC-MS runs for a given extraction method. The remaining boxes contain the number of

identical features shown as a pair-wise comparison between the methods. ( Figure reprinted with permission of American Chemical
Society from ref. 54 . Copyright 2009. Abbreviations: sulfosalicylic acid [SSA], trichloroacetic acid [TCA], perchloric acid [PCA],)

derivatization. 57 The main issues that need to
be addressed when chemical derivatization is
incorporated into sample preparation work

from negligible and deserves further study in the
context of global metabolomics.

ow

Incorporating a Derivatization Step
for GC-MS Compatibility
Methanol precipitation was also successfully
used for analysis of plasma by GC-MS after

are derivatization ef ciency, potential for

side reactions, and stability of derivatized
sample. In particular, the complete derivatiza-
tion of chemically diverse species of interest in