Chromatography

Hundreds of papers have been published on the use of Controlled Pore Glass (CPG) as a chromatographic solid phase. Its narrow pore size distribution, rigidity and chemical inertness makes it an excellent choice for size exclusion chromatography. It has been used for the isolation and  purification of viruses, proteins and cell components.

Since the surface of CPG is pure silica, it can be derivitized with a variety of bifunctional silane reagents. Thus, numerous chemical forms of CPG can be made for a wide variety of chromatographic applications. The most notable of these is Protein A-CPG which has become the gold standard for purification of monoclonal antibodies (MAB’s). Most of the major MAB drugs on the market are being purified by affinity chromatography using CPG-based solid phases. Unlike organic polymer Protein-A products, the rigidity and interconnection of CPG pores allows operation at high flow rates which are linear with pressure. The high Protein A loadings attainable with CPG, together with its low backpressures, provide higher IgG dynamic binding capacities. Thus, CPG-based media can address downstream processing efficiency problems which are a major bottleneck in high-titer MAB production.

Other forms of chemically modified CPG can be used for ion exchange, hydrophobic, chelating, enzymatic any many other modes of chromatographic interactions.

Photomicrograph of stained CPG particles showing uniformity of particle size and indicating the  distribution of the adsorbed dye within a uniform pore distribution.