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Pharma & Biopharma Manufacturing & Testing Services
Contact Us +44 (0)141 946 9999


Contact Us


+44 (0)141 946 9999

Tel +44 (0)141 946 9999


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Viral Clearance Assays and Services

Viral Clearance

Viral clearance studies are designed to assess the effectiveness of individual steps in a manufacturing process to reduce (removing or inactivating) potential contaminant viruses. The data is used from a study to provide a quantitative estimate of the overall level of virus clearance obtained during the manufacturing process. For viral clearance studies, infectivity assays are the preferred method to determine the effectiveness of a process step in removing and/or inactivating infectious agents. Valuable additional data on the partitioning of viruses can be obtained by the use of a quantitative polymerase chain reaction (Q-PCR) assay.

TSE Clearance Studies

We have taken an active role in collaborating with biotech and biopharma companies in the development of new and improved assays for viruses and TSEs. We have routinely used the TSE Western blot assay since 1997 and it is becoming increasingly more important as the need for TSE safety assessments of biologics increases. This assay specifically detects the disease-associated prion protein, PrPSc (or PrP-res). Levels of PrPSc have been shown to correlate closely with levels of infectivity. The Western blot assay provides a rapid means of making a preliminary evaluation of the effectiveness of steps in the removal of TSE agents, and can reduce the need for more expensive, lengthy bioassays.

Manufacturers must provide evidence that their manufacturing process will effectively remove and/or inactivate biological agents known to contaminate, or which may possibly contaminate, the source materials. This requirement extends to organisms other than viruses. BioReliance routinely performs clearance evaluations of manufacturing operations for the reduction of a wide range of mycoplasmas, bacteria, yeast and fungi. Additionally, evaluation of the potential genomic DNA contamination derived from such organisms can be determined.

Column Re-use Studies

With repeated use the ability of chromatography columns and other devices used in the purification process to clear virus may vary. Therefore, it is required that the reliability of reduction of virus with multiple column uses should be evaluated. We perform column resin sanitization and columns re-use studies to determine the potential for carry-over of virus and microbial agents during multiple cycles of chromatography resins. Additionally, we have extensive in-house data on the inactivation of a panel of viruses using different concentrations of the common cleaning reagent, sodium hydroxide.

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