3M™ Polisher ST is a fully encapsulated anion exchange (AEX) product to reduce host sell protein impurities, viruses, and other negatively charged contaminants in flow-through polishing chromatography of biopharmaceutical process streams.

3M™ Polisher ST can operate in most process conditions, eliminating the need for depth and membrane filtration post-viral inactivation (VI), allowing process compression. With its combination of high dynamic antibody-loading (10 kg/m²) capacities with low residence time (about 0.2 minute compared to 1 minute for chromatography resins), 3M Polisher ST opens the way to an intensity high-productivity, truly single-use purification platform. 3M Polisher ST™ is a compact footprint solution with greater capacity of delivering higher purity and yield in the downstream polishing unit operation, when compared with traditional chromatographic column, in a connected continuous downstream operation.

Ion exchange chromatography is a commonly used downstream polishing purification technique in the production of mAbs and many other therapeutic proteins. The high density of binding sites, together with a macroporous structure, enables high binding capacity for not only HCP, but also large molecules, such as viruses and DNA. The high density of binding sites and low residence times results in high mAb recovery (>95%).

The high ligand density on the advanced anion exchange membrane provides robust impurity removal and viral clearance. It also provides a 50 to 100X higher mAb load capacity than chromatography resin beads, which allows further reduction of the media volume requirement. The impurity clearance performance (HCP<1000 ppm, <100 ppb DNA, and viral clearance) is independent of the load up to 10 kg/m², enabling downsizing of the unit operation.