Downstream Development

Use of Membrane Technology in Bioprocessing Therapeutic Proteins from Inclusion Bodies of

The ultimate goal of recombinant fermentation research is cost-effective production of desired proteins by maximizing volumetric productivity (to obtain the highest amount of protein in a given volume in the least amount of time). Bioprocessing for recombinant proteins using genetically modified organisms requires a stable, high-yielding recombinant culture, a highly productive fermentation process, and cost-effective recovery and purification procedures. Escherichia coli has been a widely used host for expression of recombinant proteins (1). Its advantages lie in the enormous data…

Rapid Purification of Lys-C from Cultures

Endoproteases specific for cleavage of peptidyl bonds on the C-terminal side of lysine residues (e.g., Lys-C) are produced from a number of bacterial species, including Achromobacter lyticus (1), Pseudomonas aeruginosa (2), and Lysobacter enzymogenes (3). The Achromobacter protease 1 (API) protein has been substantially characterized (4,5,6) and shown to be a resilient enzyme that can specifically cleave after lysine residues under a wide range of buffer conditions, including high concentrations of denaturing agents such as urea and sodium dodecyl sulphate…

Purifying a Recalcitrant Therapeutic Recombinant Protein with a Mixed-Mode Chromatography Sorbent

Mixed-mode chromatography sorbents can save time and money by reducing the number of steps required to purify recombinant proteins. They also have the potential to purify proteins that single-mode sorbents cannot. As the term mixed mode suggests, these sorbents contain ligands that offer multiple modes of interaction. Although mixed-mode sorbents are used extensively in solid-phase extraction for high-pressure liquid chromatography (HPLC) sample preparation — and to a more limited extent in analytical HPLC — these resins are generally unsuitable for…

MAb Contaminant Removal with a Multimodal Anion Exchanger

Monoclonal antibodies (MAbs) constitute ∼30% of the biopharmaceutical products currently under development (1). An increasing demand for MAbs during the past decade has led to intense development of high-expression cell cultures (2). Today, it is possible to see titers of 4–5 g/L, and expression levels as high as 15 g/L and greater have been reported. As a consequence, demand has increased for more efficient downstream processes. That demand, combined with its potential for reducing time-to-market, has increased interest in the…

Modeling Flow Distribution in Large-Scale Chromatographic Columns with Computational Fluid Dynamics

Column chromatography remains a key unit operation in downstream processing of biopharmaceuticals. For most commercial processes, two to three chromatography steps are used to remove process-and product-related proteins, DNA and adventitious agents. As the biopharmaceutical industry has increased its product offerings and related demands, downstream processes have fast become a bottleneck (1, 2). Many commercial and clinical processes include a number of cycles on one or more chromatography steps to process the harvest from a single production batch. PRODUCT FOCUS:…

The Genesis of New Production Tools for Biotechnology Manufacturers

The biotechnology industry has from the start been characterized by its dependence on innovation. New therapeutics, new indications, new technologies — and the continual drive toward new approaches for optimizing processes — all contribute to getting novel products to the market (and to patients) efficiently and cost-effectively. Most of the technical literature reports on development processes for the therapeutic products themselves. But one element largely ignored forms an essential foundation to the work of the biotechnology industry: How are products…

How to Improve Your Implementation of Two-Dimensional Preparative HPLC

The biologics and natural product industries rely heavily on separation technology. Sample analyses are undertaken on the analytical scale, and isolation and purification are undertaken at the preparative scale. Key target components are often isolated to provide standard reference materials for future product quality assurance testing. These products are often very complex mixtures, requiring separation systems to have a high peak capacity for both analytical and preparative scale separations. A technique gaining popularity among companies that require the isolation of…

Proactive Debottlenecking

It wasn’t so long ago that people in the biotherapeutics industry talked about a “capacity bottleneck” to describe the difficulty faced by bioprocessors as their many products moved forth through development to require production at larger and larger scales (1). Expression technologies at the time were making proteins at levels suggesting that huge amounts of manufacturing capacity would be needed soon. Just after the turn of the century, product titers (in terms of protein present per liter of culture broth/supernatant)…

Multicolumn Chromatography

Downstream processing is a sequence of unit process operations that purify biopharmaceuticals and prepare them primarily for bulk formulation (Figure 1). Typically, a large volume (hundreds to thousands of liters containing kilograms of therapeutic protein) is delivered from an upstream fermentation or cell culture process — and this ends up as a small volume (a few liters) of purified concentrate product after processing. Figure 1: () For many years, biopharmaceutical manufacturers have been working to increase capacity, address upstream production…