SmartFlow Technologies

Purification of Viral Antigens by Continuous Diafiltration

Optimization Procedure

The SmartFlow® filter WORKS Purification of viral antigens by continuous diafiltration Optimization

Procedure from SFT is intended to purify purify viral antigens from lysed cell cultures regardless of whether the lysis was mechanical or an autolysis due to the viral infection.

This optimization procedure uses a microfiltration (MF) membrane that retains the cells and cell debris and allows the viral antigens to pass freely through the membrane. The passage characteristics of viral antigens change with different buffers, temperatures, concentrations, and membranes. By examining the passage characteristics of the different MF membranes available in the appropriate process conditions, a well defined and executed process development study can identify the most efficient membrane and process conditions to achieve the required performance.


This Purification of secreted viral antigens from cell culture protocol is intended for isolating a secreted whole virus or a viral antigen from a mammalian cell. This process has been repeatedly implemented with consistent success for isolating viral antigens excluding the smallpox, rodavirus, parvo, and hepatitis viruses.

The protocol describes the isolation of a whole virus or a secreted viral antigen from a cell culture media using a submicron microporous membrane to pass the target molecule into the permeate and retain the cells, large molecular weight broth components, and any accumulated cell debris. The protocol calls for the culture media to be concentrated 5X prior to starting the diafiltration.

Case Study

Process development scientists at a major biopharmaceutical company have looked at concentrating CHO cells while passing IgG through a MF as an alternative to centrifugation for the initial step in their downstream processing. Industrial scale cell clarification with traditional TFF formats have been subject to low flux rates and unacceptable product yields. Centrifugation combined with depth filtration is reported to provide acceptable yields but required significantly higher initial capital investment to implement.