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Regulatory authorities place stringent guidelines on the removal of contaminants during the manufacture of biopharmaceutical products. Monoclonal antibodies, Fc-fusion proteins, and other mammalian cell-derived biotherapeutics are heterogeneous molecules that are validated based on the production process and not on molecular homogeneity. Validation of clearance of potential contamination by viruses is a major challenge during the downstream purification of these therapeutics. Virus filtration is a single-use, size-based separation process in which the contaminating virus particles are retained while the therapeutic molecules pass through the membrane pores. Virus filtration is routinely used as part of the overall virus clearance strategy. Compromised performance of virus filters due to membrane fouling, low throughput and reduced viral clearance, is of considerable industrial significance and is frequently a major challenge. This review shows how components generated during cell culture, contaminants, and product variants can affect virus filtration of mammalian cell-derived biologics. Cell culture-derived foulants include host cell proteins, proteases, and endotoxins. We also provide mitigation measures for each potential foulant.
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Effective pathogen removal in sustainable natural fiber Moringa filters
Abstract Pathogen contamination of water has a massive impact on global human health. In particular, viruses pose unique challenges to water treatment techniques due to their small size and presence in water as both individual virions and when absorbed onto larger particles. Low-energy water treatment processes such as media filtration are not capable of completely removing viruses owing to their small size. Hence, less sustainable processes with high chemical or energy consumption such as chemical disinfection, ultraviolet irradiation, and membrane filtration are usually required. To overcome high energy and/or chemical requirements for virus treatment, designs for sustainable fiber filters fabricated from minimally processed natural materials for efficient virus (MS2) and bacteria ( E. coli ) removal are presented in this work. These filters were created by functionalizing readily accessible natural fibers including cotton, silk, and flax with a simple aqueous extract containing cationic proteins from Moringa oleifera seeds. The proposed filters offer a comprehensive low cost, low energy, and low environmental impact solution for pathogen removal from water with removals of >7log 10 (99.99999%) for viruses and bacteria.
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- PAR ID:
- 10355125
- Date Published:
- Journal Name:
- npj Clean Water
- Volume:
- 5
- Issue:
- 1
- ISSN:
- 2059-7037
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1038/s41545-022-00170-5
