Up to five samples/day/system were processed with start up time of less than one hour. The chromatogram in Figure 5 illustrates a portion of the data observed for the processing of a siRNA sample. Event marking indicates the various segments
of the method run. The curve data track and record all information in an electronic record. Curve data not depicted are automatically
included in the result file and can be presented at a later date if desired.
Figure 5: Example siRNA DF screening result. Left axes are ConcFactor in blue and DF X Factor in red. Right axes are LMH in
green and Feed Pressure in blue. DF=diafiltration factor, LMH=permeate flux (L/m2/hour).
Automating the ultrafiltration step of siRNA production increased the overall productivity of the group by 40% and reduced
the necessary manpower required for the project from two full-time employees (FTEs) to one. The 40% improvement was a result
of being able to process 10 samples/day on two automated systems compared with the previous approach of processing two samples/day
on three manual systems (see Table II).
Table II: Advantages of automated versus manual system setup. FTE is full-time employee.
These improvements allowed for overall cost savings while increasing the number of samples available for research. By utilizing
the instructions available in the UNICORN software for the ÄKTAcrossflow platform, a safety measure was incorporated into
the method to prevent loading sample onto a fouled filter, reducing the risk of product lost and failed experiments. The ÄKTAcrossflow
system has proven to be suitable for automated multiple sample processing using standard software and hardware with minimal
operator interaction, demonstrating an efficient means to improved process robustness.
Rebecca Arvary is a research chemist at Merck Research Labs, Merck & Co, RY818-B221, PO Box 2000, Rahway, NJ 07065 USA. *Deborah R. Cohen is a senior scientist of Fast Trak, Steven Vaughan is a field applications consultant, and Catherine Blake is a product specialist-filtration, all at GE Healthcare Life Sciences, 800 Centennial Avenue, Piscataway, NJ 08854 USA.
*To whom all correspondance should be addressed email@example.com
Article submitted: Aug. 22, 2012. Article accepted: Oct. 12, 2012.
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