Amicon® Pro Purification System – Dialysis

Desalt in a Single Spin

Buffer exchange using dialysis or diafiltration is often required to make a protein sample compatible with specific downstream analyses. But dialysis or multi-step diafiltration is time-consuming, risks sample loss and can require subsequent concentration. The Amicon® Pro device offers ground-breaking, single-spin diafiltration for simultaneous buffer exchange with concentration. Whether you’re performing this step simultaneously with elution from resin (see Purification section) or whether you’re performing diafiltration only, you’ll experience the same high diafiltration efficiency designed into the device. 

Advantages of reducing number of spins for buffer exchange:

  • Sample is not repeatedly diluted and re-concentrated
  • Less chance of protein aggregation
  • Decreased chance of protein precipitation
  • Maintains high protein activity
  • Saves time

Buffer Exchange

Click image to enlarge

1,000-fold buffer exchange in a single spin.
Protein (purple dots) is dissolved in Buffer 1 (yellow) during the concentration step (left). During the buffer exchange step, 1.5 mL of Buffer 2 (blue) is added. Arrows indicate direction of fluid flow, showing that Buffer 2 enters the sample continuously while Buffer 1-containing solution is being forced out.

Diafiltration (Buffer Exchange)

Compare the Amicon® Pro Workflow with Traditional Methods:
 

Diafiltration Dialysis (cassettes, tubing) + concentration device Centrifugal diafiltration devices - 0.5 mL Amicon® Pro Purification System
Process time 17 hours 45 minutes 15 minutes
Steps required 6 4 2
Sample transfers 2 0 0

The Gentleness of Dialysis with the Efficiency of Diafiltration

Gentler Buffer Exchange = Greater Activity.
 

  Dialysis cassette +
concentrator
Diafiltration device
(3 spin) - 0.5 mL
Amicon® Pro Purification System
Process time 16 hours 50 minutes 20 minutes
Recovery 51% >95% >95%
Specific activity
(signal/mg GST-LLP)
0.195 0.17 0.199