After 2-D gels are stained, the protein patterns are digitized and analyzed. Following analysis, spots of interest are then excised from gels for further analysis. Bio-Rad provides a wide assortment of imaging systems to meet various 2-D gel imaging requirements. Sophisticated image analysis software simplifies the analysis of 2-D data and makes the process more efficient by automating spot detection and analysis. This section provides an overview of gel image acquisition instruments and analysis software.
Related Topics: Protein Sample Preparation for 2-D Electrophoresis, First Dimension Separation (Isoelectric Focusing), Second Dimension Separation, Visualization (Staining), Protein Spot Excision and Protein Identification, and Troubleshooting 2-D Electrophoresis Gels with 2-D Doctor™.
Analysis of high-quality 2-D gels is a basic requirement for investigating changes in protein expression. Before 2-D gels can be analyzed with an image evaluation system, they must be digitized. The most commonly used devices are camera-based systems, densitometers, phosphor imagers, and fluorescence scanners. Bio-Rad has imaging equipment suitable for different kinds of detection methods.
|ChemiDoc™ MP||Gel Doc™ EZ|
|Type of Imager||Densitometer||CCD camera-based||CCD camera-based|
|Light source options||Epl- and transillumination of white light||Transillumination of UV and white light with near infrared, far red, red, green, and blue LEDs||Transillumination of UV and white light|
|Fluorescent stains and labels||—||•||—|
Computer-assisted image analysis is an indispensable tool for the evaluation of complex 2-D gels. Image analysis software obtains quantitative and qualitative information about the proteins in a sample and stores the information in files, which may also contain additional annotations. PDQuest™ 2-D analysis software is a tool for analysis of digitized gel images that integrates with Bio-Rad's image acquisition instruments.
The wizard driven software uses the following work flow:
PDQuest can also be used to control the ExQuest™ spot cutter for automated spot excision.
After separation by 1-D gel electrophoresis, you can utilize a number of methods for protein imaging and analysis involving staining techniques or stain-free technology in combination with specialized imaging devices and accompanying software.