Sample Depletion, Fractionation, and Enrichment for Biomarker Discovery - Proteomic and Metabolomic Approaches to Biomarker Discovery - page 230

CHAPTER
15

Sample Depletion,
Fractionation, and Enrichment
for Biomarker Discov ery

Haleem J. Issaq, Timothy D. Veenstra
Laboratory of Proteomics and Analytical Technologies, Advanced Technology Program,
Frederick National Laboratory for Cancer Research, Frederick, MD, USA

OUTLINE

Introduction 237 Isoelectric Focusing 241

Depletion 238 Size Exclusion Chromatography 242

Fractionation Procedures for Proteins
and Metabolites

Conclusions 243

238

References 243

Af nity Chromatography 241

INTRODUCTION concentration, and separation procedures in the

hope of detecting the largest possible number of
compounds. Many attempts have been made in
the last 20 years by analytical chemists to develop
methods that possess suf

The strategy for the discovery of protein or
metabolite biomarkers aims for the identi

cation
of all the proteins and/or metabolites in a sample.
Obviously, complete proteome and metabolome
coverage is presently impossible due to a number
of factors, including their dynamic nature. The
complexity of the proteome and metabolome
requires the development of ef

cient resolution to sepa-
rate the components of the proteome and metab-
olome as well as enough sensitivity to detect
compounds present at the lowest abundances.
Because the physicochemical nature of the metab-
olome and proteome differ, they require different
fractionation and separation procedures. The

cient analytical
methods that involve depletion, fractionation,