Control of leached beta-glucan levels from depth filters by an improved depth filtration flush strategy.

Beta-glucans are polysaccharides of D-glucose monomers linked by (1-3) beta-glycosidic bonds, are found to have a potential immunogenicity risk in biotherapeutic products, and are labeled as process contaminants. A common source of beta-glucans is from the cellulose found in traditional depth filter media. Typically, beta-glucan impurities that leach into the product from the primary clarification depth filters can be removed by the subsequent bind-and-elute affinity chromatography capture step.