A form of electrophoresis in which a gel or membrane is run in one direction, rotated 90o, and run again under a different set of conditions (so as to gain a different separation of components). 2D gel electrophoresis is a powerful technique for protein separation, purification, and analysis.
first run
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| | | * | |second
| | | | | run
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| | | * | v
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Also written '2D electrophoresis'. | 
