K-Patents has released a new application note on protein concentration and diafiltration. Diafiltration is a technique using ultrafiltration (UF) membranes to separate the components of solutions and suspensions based on their molecular size, although other factors such as molecular shape and charge can also play a role. Molecules larger than the membrane pores in the UF membrane will be retained at the surface of the membrane while solvent and smaller solute molecules will pass freely. This process of molecular exclusion at the UF membrane surface leads to concentration of the protein solute in the retained fraction. The protein solute (retentate) can then be recovered from above the membrane.
K-Patents PR-23-AC Pharma Refractometer provides an accurate real-time measurement of the protein concentration. The refractometer aids in controlling and adjusting concentration levels after ultrafiltration.
Ref. 6.01.46 Protein Concentration and Diafiltration (pdf)