A simple device for protein concentration by steady-state stacking

Preparative polyacrylamide gel electrophoresis with continuous elution flow gives rise to protein eluates at a very high degree of dilution. To concentrate such eluates with a minimum of effort, a new device was designed, constructed, and tested. This device is capable of simultaneously concentrating, by use of steady-state stacking, the eluate under an elution peak, divided into ascending, center, and descending fractions, comprising as much as 100 ml each. Final volumes were 1.5 ml per fraction. Protein recovery was 70–80%.