Nonamphoteric isoelectric focusing: II. Stability of borate-glycerol pH gradients in recycling isoelectric focusing.
By complexing polyols with borate in recycling isoelectric focusing and by varying the ratio of polyol to borate over the useful pH range of 4.0-6.0, it is possible to control pH. Twelve solutions of 0.1 M boric acid and varying glycerol concentration were used to vary pH in a twelve-compartment commercial recycling isoelectric focusing (RIEF) system. Various concentrations of boric acid were tested as anolyte, and various Tris(hydroxymethylamino)methane-borate buffer systems were tested as catholyte. Electroosmosis, hydrogen ion flow, and fluid balancing were characterized in two glycerol gradients; one was maintained at 0.06 pH/fraction and the other at 0.12 pH/fraction. In the latter case, ovalbumin (pI4.70) migrated to the pH 4.61 and 4.72 compartments. It is concluded that the borate-glycerol system can be adequately stabilized in RIEF for isoelectric purification of certain proteins.
Todd
P
P
Bioprocessing and Pharmaceutical Research Center, Philadelphia, PA.
Elsasser
W
W
D001881:Borates; D004058:Diffusion; D005990:Glycerol; D006863:Hydrogen-Ion Concentration; D007525:Isoelectric Focusing; D011506:Proteins / Q000737:chemistry*; D012995:Solubility
D001881:Borates; D011506:Proteins; D005990:Glycerol