Immobilized pH gradients IPG

Because the pi of a protein is based on its amino acid sequence, this technique has good resolving power. The resolution can be adjusted further by changing the range of the pH gradient. The use of immobilized pH gradient (IPG) strips has enabled reproducible micropreparative fractionation of protein samples, which is not consistently possible when ampholytes are used in the first dimension (Gorg et al., 2000). 

The majority of proteomic investigations employ two-dimensional gel electrophoresis (2-D) with immobilized pH gradients (IPGs) to separate the proteins in a sample and combine this with mass spectrometry (MS) technologies to identify proteins. 

The technique of immobilized pH gradients (IPG) in isoelectric focusing was first announced to the scientific community at a meeting of the International Electrophoresis Society in Athens, April 1982, as the result of an intensive collaborative effort (Righetti et al., 1983c Bjellqvist et al., 1983 Gorg et al., 1983). It seems extraordinary that in only two and one-half years the method was developed to such an extent as to call for an extensive review. When conventional isoelectric focusing (lEF) was developed in 1960 (Svensson, 1961, 1962), it took a full decade before the scientific community became aware of it. 

The introduction of the immobilized pH gradient (IPG strip) greatly enhances the potential of 2DE (Righetti and Bossi, 1997 Fichmann, 1999 Gorg et al, 2000). This is... 

Righetti, P. G., and Tonani, C. (1991) Immobilized pH gradients (IPG) simulator—An additional step in pH gradient engineering. Electrophoresis 12, 1011-1027. 

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