2011 Collection Archives - Page 2 of 2 - BioProcess InternationalBioProcess International

Changes in Media Composition due to Expression of IgG in HEK293 and CHO DG44 Cells

Quality of recombinant/therapeutic proteins produced by engineered cell lines is a concern shared by both manufacturers and regulatory agencies. New assays are needed to facilitate earlier and more rapid analysis of therapeutic protein quality. Cell culture supernatant contains secreted proteins that are indicative of the cellular condition and thus are potential indicators of recombinant protein quality. This study identified changes in secreted host cell proteins (HCP) from cell pools exhibiting varying levels of recombinant antibody expression as determined by quantitative…

Fc-Specific Mix-Mode Ligand for Monoclonal Antibody Purification

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APT1604 is a base-stable 600 Da peptidometic ligand coupled to a 6% cross-linked agarose matrix. APT1604 binds to Fc-fragment of monoclonal antibodies (mAb) and various immunoglobulin (IgG) subclasses. The interaction between protein and ligand has been suggested to result from mixed mode ionic – hydrophobic interactions, albeit with high selectivity for immunoglobulins. The main application area for APT1604 is purification of mAb from mammalian cell harvest, but it can also be used for purification of IgG from other sources. The…

Factory of the Future

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Fed-batch and perfusion culture are two dominant modes of operation for mammalian-cell-culture based processes. Challenges in the industry (such as competitive products for the same indication or desired cost reductions) are forcing many to explore new production options. Increasingly popular is the application of the ATF™ System to generate ultra high viable cell concentrations (>100m cells/ml) for a “concentrated” or “intensified” process. The use of the ATF System in a typical concentrated fed-batch process is shown which has generated a…

Current advances in Protein A chromatography

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In this work we present results with a novel high capacity Protein A medium prototype based on high flow agarose. The medium prototype was optimized for higher dynamic binding capacity (DBC) at long residence time. A 20–50% higher DBC was obtained compared to MabSelect SuRe™. DBC was independent of MAb concentration in the range 1–10 g/L. Optimization of elution conditions (pH and flow rate) was performed by design of experiments. A lifetime study for 100 purification cycles, performed with a…

Sartorius Stedim Biotech Filtration Trials with SAFC Ex-Cell Hydrolysate Fusion

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SAFC has launched EX-CELL® CD Hydrolysate Fusion, the first fully chemically defined media supplement of its kind in the industry. Sartorius Stedim Biotech and SAFC Biosciences have recently announced a wide-ranging joint cooperation agreement to serve their customers. As a consequence of this effort, a range of 0.2 μm & 0.1 μm sterilizing grade filters from different membrane materials were tested for throughput & biological activity post-filtration. This paper provides an insight into superior total throughput performance of the Sartorius…

Improving influenza vaccine quantification; a comparative study of SRID and SPR

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Reliable analytical tools are valuable for economical process development, production, and batch release of vaccines. The current method recommended by the European Pharmacopoeia and WHO for determination of influenza virus titer ¬ single radial immunodiffusion assay (SRID) is straightforward and easy, but leaves plenty of room for improvement when it comes to assay variability and speed of analysis. In addition to having low sensitivity and precision, the method is both time-consuming and quite labor-intensive. In this study a Biacore™ assay…

Optical Oxygen and pH Sensors for Monitoring Biofermentation Processes

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Advances in high-performance sensor materials and optoelectronics have enabled optical sensors for use in markets including the life sciences, environmental, food and beverage, process control and biotechnology. Compared with traditional electrochemical sensing techniques such as galvanic, paramagnetic and fuel cell sensors, these optical sensors can be made in small and customizable form factors such as probes and self-adhesive patches. The sensors also have fast response, provide long-term stability and are chemically inert. This experiment demonstrates the viability of optical sensors…

Critical aspects for mixing of stratified solutions in vertical bags

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With increasing use of single-use, disposable fluid processing systems, concerns of mixing arise in processes such as protein concentration, clarification and diafiltration. For some operating conditions of flow rate, solution viscosity or flow path configurations, protein solutions may become stratified in vertically-oriented hanging bags. This can cause decreased efficiency in cross flow applications. In this study, we modeled a stratified solution and tested the influence of these various operating conditions using ReadyCircuit* 2-D pillow bags. Even with viscous materials, flow…

Facing the Challenges in Bio-Pharmaceutical Production

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Much attention has been given to ion exchange (IEX) media as a means to improve productivity as a result of increasing demand for higher efficiency on the downstream process. Until recently, strain optimisation for high productivity and upstream purification were the bottlenecks for most bio-processes. However, with the progress made in recent years, titers in fermentation processes have increased significantly. Obviously, this increased volumetric productivity will help reducing the cost of goods, but it also has an impact on the…