Direct recovery of proteins into a free-liquid phase after preparative isoelectric focusing in immobilized pH gradients

J Biochem Biophys Methods. 1986 Oct;13(3):151-9. doi: 10.1016/0165-022x(86)90088-6.

Abstract

A new method for electrophoretic retrieval of protein zones from Immobiline matrices is described, based on elution directly in a free liquid phase, rather than in ion-exchange beads or molecular sieves, as previously described. The chopped Immobiline gel is loaded on top of a 5% T stacking gel, 6-10 mm in height, and forced to transverse it and collect into a chamber, filled with 20% sucrose solution, closed on its anodic side by a dialysis sac. The transfer is practically quantitative, for most proteins, after 30-60 min of zone electrophoresis at 10 W (300 V potential differential). Recovery of protein mass is in general better than 90%, while for enzyme activity is in the range of 60-80%. For preserving enzyme integrity, the following precautions are recommended: short electrophoretic times; avoidance of anodic oxidation; chilling of the buffer in the anodic chamber; and use of low levels (2-5 mM) of the specific enzyme substrate throughout the entire electrophoretic system (cathode, anode and gel plug).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Enzymes / isolation & purification
  • Hemoglobin A / isolation & purification
  • Isoelectric Focusing / methods*
  • Proteins / isolation & purification*
  • Solubility

Substances

  • Enzymes
  • Proteins
  • Hemoglobin A