A Disposable Valve For Process Chromatography

By Michael Gagne, President, Aquasyn LLC

The Challenge:
The manufacturer required a fully automated, disposable chromatography system which was PLC controlled and designed for use in a cGMP environment. The required applications for the chromatography system included contamination removal, and concentration and purification of biologically derived proteins used in the production of research and clinical materials. Finally, there was a requirement that all product contact surfaces be completely disposable, single-use applications.

The Technical Problem:
There were a number of problems with the original valve set-up for the chromatography system that needed to be addressed with an operational solution. The closure capability of the existing valve and tubing combination was unpredictable and the durometer tolerance variations within the elastomer tubing sets led to frequent valve failures, or leak-by. This also occurred when the valves were unable to overcome the operational pressure resistance generated within the system. If they were able to close, it was at a very low pressure for both the tubing and the valve. When the pressure issues were combined with tubing durometer variances, it was difficult to determine which component was to blame. Additionally, there was often product degradation caused by convective heat transfer from the actuation of the valve through the liner, and into the product stream. These issues alone compromised the system’s overall integrity and ability to function as needed.