Elimination of basic gaps at high pH values in 2-DE.
The appearance of gaps, vertical lanes lacking protein spots at the cathodic end of 2-D maps generated with wide range IPG-strips exceeding a pH value of 9, is shown to depend on the electro-osmotic transport of water into the IPG-strip. Substitution of urea solution with water is demonstrated to increase the hydrolysis rate of polyacrylamide in IPG-strips explaining the gap formation. The use of 8 M urea or thiourea/urea solutions in the electrode wick enables overnight focusing without the appearance of gaps.
Kask
Lena
L
GE Healthcare Bio-Sciences AB, Uppsala, Sweden. lena.kask@ge.com
Larsson
Kjell
K
Bjellqvist
Bengt
B
D015180:Electrophoresis, Gel, Two-Dimensional / Q000379:methods*; D004926:Escherichia coli / Q000737:chemistry; D029968:Escherichia coli Proteins / Q000032:analysis; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D011506:Proteins / Q000032:analysis*; D014508:Urea / Q000737:chemistry
D029968:Escherichia coli Proteins; D011506:Proteins; D014508:Urea