Filtration

Industry Adoption of Membrane Adsorbers

Membrane adsorbers (MAs) are the fastest-growing segment in single-use bioprocessing. But their future is not entirely certain. According to BioPlan Associates’ latest survey of biopharmaceutical manufacturing, the MA market has been growing at ~20% annually since 2006 (1). Paradoxically, however, the segment may not be a true “rising star.” Our study also shows that MAs remain among the least-often adopted devices among biomanufacturers. So the question of how and whether MA technology can revolutionize bioprocessing remains open. Market for Membrane…

Increasing Purity and Yield in Biosimilar Production

Current downstream processing strategies for recombinant proteins often require multiple chromatographic steps, which may lead to poor overall yields. Product purification can be especially difficult when a target protein displays reduced stability, forms isoforms or misprocessed variants, or needs to be purified from a complex mixture containing a high degree of contaminants. One technology that has been developed to tackle such limitations is based on custom-made chromatography matrices containing camelid-based single-domain antibody fragments. With a molecular weight of only 12–15…

Artifacts of Virus Filter Validation

Virus filters are used in biomanufacturing to ensure the safety of biopharmaceutical drug products. As part of filter implementation, manufacturers are required to validate that the filtration process can indeed remove virus. Validations are typically performed at contract testing organizations (CTOs) that are “equipped for virological work and performed by staff with virological expertise in conjunction with production personnel involved in designing and preparing a scaled-down version of the purification process” (1). Virus removal capability of a filtration process is…

Downstream Technology Landscape for Large-Scale Therapeutic Cell Processing

The cell therapy industry (CTI) is poised to grow rapidly over the next decade, treating millions of patients and generating annual revenues into the tens of billions of US dollars (1, 2). To meet that high-growth demand, large CTI system manufacturers (e.g., Corning, Nunc/Nalgene, and GE Healthcare) and leading contract manufacturing organizations (CMOs, such as Lonza) are developing and integrating new upstream technology platforms such as gas-permeable membranes and microcarrier-based bioreactors to significantly increase therapeutic cell culture productivity. As those…

Advocating an Evolution

In a 2006 report, the US Department of Health and Human Services hailed regenerative medicine as “the vanguard of 21st century healthcare” and “the first truly interdisciplinary field that utilizes and brings together nearly every field in science” (1). To fuel support for regulatory, legislative, and reimbursement initiatives in this new therapeutic class, a small group of scientists, life science business executives, patient advocates, and other experts formed the Alliance for Regenerative Medicine (ARM, http://alliancerm.org). Starting with 17 charter members,…

Performance of a Salt-Tolerant Membrane Adsorber in Flow-Through Mode

Monoclonal antibodies (MAbs) have become the most prevalent therapeutics in the biopharmaceutical industry. Their downstream purification typically involves protein A chromatography as a capture step followed by one or two additional chromatographic polishing steps. Additional unit operations dedicated specifically for viral clearance (e.g., viral inactivation and filtration) are added to ensure product safety. According to a survey of Amgen processes, after processing through a protein A column, only trace amounts of impurities such as Chinese hamster ovary cell protein (CHOP)…

Integrity Testing of Ultrafiltration Systems for Biopharmaceutical Applications

    Ultrafiltration (UF) is a membrane-based separation technology commonly used in the biopharmaceutical industry for concentration or diafiltration of protein solutions to remove low–molecular-weight (LMW) impurities or exchange buffers. The nominal MW limit of UF membranes ranges from 1,000 Da (1 kDa) to 1,000,000 Da (1,000 kDa). A target product is retained by the membrane while lower-MW solutes or impurities pass through (1). For a target product with a smaller MW than the impurities, separation is accomplished by allowing…

Sterilizing-Grade Filter Sizing Based on Permeability

    Sterilizing filtration renders biotherapeutics free of biocontamination. In many cases, sterilizing-grade filters also reduce bioburden or facilitate closed or aseptic processing. They are used to filter active pharmaceutical ingredients (APIs), formulated bulk, cell culture media, buffer, additives, process intermediates, and so on. Such applications are often critical for ensuring a successful batch operations. Nonetheless, a significant amount of time and resources are typically not devoted to establishing filter sizing requirements for “simple” applications such as buffer filtration. Here,…

A Decade of Filtration

    Filtration is just as vital to bioprocessing as chromatography — and arguably even more so. Filters are not only used as downstream unit operations in themselves, but also in support of nearly every other step in bioprocessing. Gas or liquid filters ensure the quality of incoming air and feeds for cell culture operations, clean the circulating media in perfusion processes, aid in harvest clarification, and remove buffers from chromatographic eluate after chromatography columns. They are used in formulation…

Large-Scale, Single-Use Depth Filtration Systems

    Clarifying cell culture broth is the first downstream unit operation in an elaborate sequence of steps required to purify a biological therapeutic. A combination of centrifugation, depth filtration, or tangential-flow filtration (TFF) is used for that operation. The availability of largescale, single-use, depth filtration technology in the recent years, however, has given process developers the capability to improve and simplify downstream processes.   Clarification of Cell Culture Streams   The main purpose of clarification is to efficiently separate…