Unlock Exclusive Discounts & Flash Sales! Click Here to Join the Deals on Every Wednesday!

Analysis of Human Serum Proteome - Separation and Identification of Proteins by Two-dimensional Electrophoresis (2-DE/2D-PAGE) (CAT#: STEM-ET-0346-ZJF)

Introduction

We provide 2-DE service for separation and identification of proteins from human serum. Plasma, the soluble component of the human blood, is believed to harbor thousands of distinct proteins, which originate from a variety of cells and tissues through either active secretion or leakage from blood cells or tissues. The dynamic range of plasma protein concentrations comprises at least nine orders of magnitude. Proteins involved in coagulation, immune defense, small molecule transport, and protease inhibition, many of them present in high abundance in this body fluid, have been functionally characterized and associated with disease processes. For example, protein sequence mutations in coagulation factors cause various serious disease states.




Principle

Two-dimensional gel electrophoresis (2DE) is a form of gel electrophoresis commonly used to separate and analyze proteins by molecular charge and molecular size. Proteins are first solubilised in a denaturing buffer containing a neutral chaotrope, a zwitterionic or neutral detergent, and a reducing agent. In the first dimension, proteins are separated by their isoelectric point (pl) in isoelectric focusing (IEF). In the second dimension, proteins are separated by molecular weight in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Each protein is therefore resolved at a unique isoelectric point/molecular weight coordinate. After visualisation by staining proteome changes are revealed by gel image analysis, and protein spots of interest excised and identified by mass spectrometry sequence analysis combined with database comparison.

Applications

Proteomics, genetics, human serum proteome, clinical analysis

Procedure

1. Preparation: Proteins are usually solubilised in a denaturing buffer containing a neutral chaotrope, a zwitterionic or neutral detergent, and a reducing agent. The procedures of sample preparation are dependent on the sample type.
2. Isoelectric focusing (IEF): In a particular pH gradient, proteins are separated by differences in their isoelectric points.
3. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE): Proteins are separated based on the differences in their molecular weight.
4. Visualisation: Visualization of proteins by silver or coomassie brilliant blue staining.
5. Determination: Determination of molecular weight, pl, amount and others results by gel image analysis and mass spectrometry sequence analysis combined with database comparison.

Materials

• Isoelectric focusing and gel electrophoresis apparatus
• Sample solution
• Buffer solution and SDS-polyacrylamide gel