Preliminary metabolic screening method for clone selection in the ambr15

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Conference Program

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What Makes a Great Science Experience? A Program Planning Checklist for Educators

The Science & Technology Program Work Team at Cornell University wanted to know what constitutes a fun, exciting, and successful science-based learning experience for young people. In 2002, 4-H Educators and youth were engaged in the Concept System process that generated 144 unique ideas. These ideas were distilled into 15 clusters, all of which linked to three principal elements of program design: Content, Context, and Delivery. Those results were translated into a checklist for planning science programs, available at . In 2005 and 2006, the team recommended adapting it to other interactive learning experiences and for program evaluation

Continuous counter-current affinity colloidal purification

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Continuous Counter-current Dialysis (C3D) - the Future of Diafiltration

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Considerations for an incubation chamber for continuous viral inactivation

Continuous bioprocessing offers numerous benefits that have been highlighted recently in the literature. While substantial research efforts have allowed for relevant developments in continuous cell culture processes, downstream challenges, such as continuous viral inactivation, have not been addressed. The purpose of this work is to design a chamber that incubates a continuous product stream for a desired incubation time, typically for 1 hour. Since plug-flow cannot be achieved at typical incubation times and flow rates, one of the biggest challenges is to address dispersion of the product stream. Since several logs of viral clearance should be achieved during a virus removal step, the restriction is that only 1-10ppm of the original product should exit the chamber before the specified time. In this work, an initial design is chosen such that the incubation chamber is easy to handle, has a small footprint, and there are no pressure concerns at the desired flow rates. Pulse response experiments have been performed to generate cumulative residence time distribution functions. The average residence time distribution function was used to find the time at which 1 ppm of the original tracer concentration passes through the chamber. An orthogonal method should be used to verify that the diluted tracer concentration falls under the predicted value at the desired time. Thus, the starting tracer solution must be concentrated enough such that a concentration of 1 ppm can be measured by a highly sensitive technique. In this work, a tracer solution and a method of detection were selected. Preliminary results of chamber design will be shown and current challenges will be shared

Development of highly intensified cell culture perfusion media and process with tremendous productivity potential, while having a low cell bleed requirement for maintaining an overall high yield

Process intensification leveraging perfusion offers immense opportunities for yield improvement over fed-batch processes for the production of monoclonal antibodies. In the context of continuous processing, the goal is to achieve highly intensified perfusion processes that allow substantial footprint reduction and enable flexible adaptation in new facilities. Developing a productive and efficient perfusion process requires not only the application of the “push-to-low” concept for reducing the perfusion rate requirement, but also requires in-depth mechanistic development of medium formulations in order to decrease byproduct waste generation, reduce unproductive cell growth and increase productivity. Specifically reducing the usage of cell bleed is particularly desirable for improving the overall yield, since as much as 30% of the generated product may be lost through the use of cell bleed. In this work, we share case studies of perfusion medium development studying classical components such as vitamins and salts that can be manipulated to have profound effect for controlling the cell growth and reducing the use of cell bleed. In one case, the cell bleed rate was reduced down to as low as zero, while still being able to maintain a highly viable culture. Furthermore, in some cases, significant increase in the cell specific productivity (qp) was achieved when the perfusion culture was switched to a growth suppressed mode. In one example, the qp increased from 30 pg/cell/day to as high as 115 pg/cell/day when the cell growth was arrested. This led to increased daily volumetric productivities of 3 to 5 g/L/day compared to the control of 1 g/L/day. Cell cycle analysis of the arrested culture by flow cytometry also revealed an induced state of elevated cell population in the G0/G1 phase, which is generally considered as the most productive state of the cell cycle. In order to integrate the cell growth control strategy described herein, a two stage perfusion concept is designed where the first stage focuses on rapid accumulation of cells to reach the target cell density, and the second stage switches to a slow growth, yet highly productive and viable perfusion culture

A truly continuous counter-current downstream

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Computational Fluid Dynamics (CFD) modelling and experimental confirmation of hollow fiber tangential flow filtration (HFTFF) and alternating tangential flow filtration (ATF) In a perfusion bioreactor

Hollow fiber tangential flow filtration (HFTFF) and Alternating tangential flow filtration (HFATF) are technologies of choice in continuous (perfusion) bioreactor operations. A major drawback of these technologies is membrane fouling and associated reduction in membrane permeability. Membrane fouling leads to a gradual decline in trans-membrane flux and the sieving of the protein product. Additionally, experimental data suggests that under otherwise similar conditions protein sieving may be different in TFF vs. ATF, indicating that flow behavior patterns in the two technologies may be different. Many models of fouling and protein sieving have been reported in the literature for HFTFF. In comparison, however, there is limited research work on HFATF, making it hard to compare mechanisms of fouling and product sieving between HFTFF and HFATF. Additionally, almost all mechanisms of fouling and predictive models make sweeping assumptions with regards to the complex flow patterns prevailing in HFTFF and HFATF. In this study, we provide experimental data and computational fluid dynamics (CFD) information to gain insight into factors that impact fouling and product sieving. Specifically, first we present the confirmation of CFD model outputs by comparing experimentally measured trans-membrane flux and pressure with model predictions. Next, we compare the CFD model predictions of pressure drop, shear rate profile and axial and radial fluid velocity distributions between HFTFF and HFATF. Subsequently, we investigate the shear effect on cell damage, using the concept of constant Camp number, defined as Gt = constant, where G is the prevailing shear rate and t is the exposure time. Our CFD model predicts that shear rate (G) and hence the resulting stress experienced by cells in HFATF has a distribution that is determined by the operation of the diaphragm pump. Finally, we use CFD to compare Gt profile generated by imposing different pump condition

Viral clearance considerations for continuous viral inactivation

Continuous low pH viral inactivation has been considered by Boehringer Ingelheim, Pfizer, and other companies who are investing in integrated processing. In continuous viral inactivation, a critical parameter that poses a new challenge is the exact incubation time of the product stream. In a continuous space, the concept of time translates in the product flow rate, incubation volume, and dispersion effects. To address dispersion, we define the minimum residence time, tmin, as the time when the first product element exits the tubular chamber. In this work, we characterize the tmin for a novel, scalable, and sturdy tubular reactor design that can serve as an incubation chamber for a process capable to produce \u3e1kg of product. In addition, we provide robust data for a scale down model suitable for viral studies. We propose an innovative in-line spiking methodology to validate the minimum residence time using viruses. This methodology can be used as a viral clearance platform for continuous low pH virus inactivation. Finally, we propose a trace response method to be used as a way to verify that the process was properly set up