Multidimensional HPLC in Proteomics

Proteomics is an emerging field of intensive research in the post-genomic era that involves the global analysis of gene expression, including identification, quantification, and characterization of proteins [114,115]. Although proteins are a translated version of genes, the complexity of proteins is enormous. As many as 1 milhon proteins can exist in the proteome. An estimated 20,000 proteins are expressed in a particular type of cells at any time. All proteins do not 

Extract Protein/ Protein Drug Complex to Waete 

To reduce the complexity of proteins expressed in the cell and overcome the differences in expression rates of proteins, prefractionation techniques have to be deployed before further protein characterization [116]. Two current approaches include electrophoretic and chromatographic methods. 

The prefractionation technique provides improvements in separation resolution, increased sensitivity, and enhanced ability of loading a much higher amount of sample in any narrow pH interval in gel electrophoresis. Once the complexity of proteins is reduced by prefractionation, individual fractions can be subjected to either 2D gel electrophoresis or multidimensional HPLC for further separation, followed by MS analysis. 

Since the beginning of 2D gel electrophoresis about 30 years ago [121], it has become a method of choice for high-resolution protein separation [122]. On a 2D gel, up to thousands of proteins expressed by an organism or cell can be separated followed by identification with MS [123]. Traditionally, a 2D gelmatching procedure (gel imaging) can be used to compare two sets of protein 

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