Downstream Processing

Inactivation of Enveloped Viruses: Seeking Alternatives to a Problematic Surfactant

Triton X-100 detergent makes an interesting case study in bioprocess sustainability strategy. Also known as octylphenol ethoxylate (OPE), this nonionic surfactant has many uses in biopharmaceutical research and development. Among other laboratory applications, it is used to lyse cells and DNA in research, to solubilize membrane proteins and decellularize animal-derived tissues, to reduce the surface tension of aqueous solutions during immunostaining, and to remove sodium dodecyl sulfate (SDS) from polyacrylamide gel electrophoresis (PAGE) gels for analysis. It also serves as…

Intensification of Influenza Virus Purification: From Clarified Harvest to Formulated Product in a Single Shift

Influenza is a global respiratory disease with an estimated mortality of up to a half million people per year (1). The majority of traditional influenza vaccines are still produced in eggs. Downstream processing typically consists of clarification by centrifugation, concentration by ultrafiltration, and purification by ultracentrifugation (2). Recombinant vaccines are most often purified by chromatography. Chromatographic purification of viruses already has achieved major improvements in recovery and scalability (3), but it also is important because it enables virus purification to…

Sticking In or Standing Out? Dichotomy in Vaccine Purification By Chromatography

A general vaccine purification strategy can be divided into three stages, with one or more steps for each stage. The first stage is to concentrate and isolate the target molecule quickly to remove it from conditions that could lead to its inactivation or loss. Intermediate purification seeks to remove remaining contaminants, typically using an orthogonal approach. That is followed by a polishing step in which trace impurities are removed through high-efficiency steps because those impurities usually are similar to the…

Process Analytics and Intermediate Purification of Bispecific Antibodies with a Non-Affinity Platform

The therapeutic benefits of monoclonal antibodies (MAbs) have been demonstrated in recent decades with uncontestable success as treatments for human disease. Despite MAbs’ key features such as specificity, selectivity, and safety, the format has limitations (1, 2). Bispecific antibodies may overcome number of difficulties (3). Multiple formats of bispecific antibodies have been developed, although only the κλ-body is fully human and devoid of linkers or mutations. It requires no genetic modifications of heavy and light chains and results in bispecific antibodies…

Virus Segregation During Purification Processes: Calculation of Critical Potential Carryover of Viruses

Before a pharmaceutical product is introduced into humans, either in a clinical trial or as a marketed product, virus safety must be evaluated carefully. Virus safety normally is ensured using a three step complementary approach: selecting and testing cell lines and/or raw materials for the absence of viruses, testing the product at appropriate steps of production, and assessing the capacity of a production process to clear infectious viruses (1). The latter (also referred to as viral clearance) is the subject herein. Spiking studies are conducted to evaluate the capacity of a purification…

A UF–DF Screening System for Bioprocess Development: Efficient and Cost-Effective Process Fit and Scale-Up to Manufacturing

Ultrafiltration and diafiltration (UF–DF) of therapeutic proteins are performed in either tangential or crossflow mode using membrane filters. UF–DF plays a critical role in both downstream and upstream processes for the biopharmaceutical industry (1). In upstream production processes, classical tangential-flow filtration (TFF) or alternating tangential-flow (ATF) systems are used in high–cell-density perfusion for protein expression by cell culture (2). TFF is used in downstream processing for UF–DF and concentration of therapeutic proteins. TFF unit operations are common in protein purification…

eBook: Development and Application of a Simple and One-Point Multiparameter Technique — Monitoring Commercial-Scale Chromatography Process Performance

In commercial-scale biopharmaceutical manufacturing, downstream chromatography steps are still a bottleneck and contribute to significant operational costs (1, 2). Some of those costs are inherent (e.g., resins, large buffer quantities, and cleaning) whereas others are avoidable (e.g., product loss due to rejected lots or deviations that result in production downtime). Maintaining efficient and robust chromatography process performance is therefore critical for minimizing operating costs. To do so, we introduce a simple and one-point multiparameter technique (SOP-MPT) for monitoring chromatographic process…

The Multi-Mode Mimetic Ligand Library: A New Tool for Rapid Development of Downstream Processes

Recent developments in downstream processing of biomolecules — including continuous processing, bind–elute affinity capture, and flow-through polishing steps — have increased the need for greater selectivity from chromatography adsorbents. This has led to the introduction of a new generation of adsorbents: so-called “mixed-mode” or multimodal ligands. They provide greater selectivity and tolerance to process buffer composition than either ionexchange chromatography (IEC) or hydrophobic-interaction chromatography (HIC) alone can provide. Learn more in this Special Report from Steve Burton, Chief Executive Officer…

Scale-Up of Twin-Column Periodic Countercurrent Chromatography for MAb Purification

Periodic countercurrent (PCC) processes increasingly are being evaluated as alternatives to single-column batch capture processes. Some of the advantages of PCC processes over single-column processes include shortening of processing time and/or reduction of required resin volume through increased productivity; reduction in resin costs through improved resin capacity use; and reduction in buffer consumption through increased column loading. Those advantages, however, come with increased equipment complexity and hardware costs. PCC processes and systems with two to up 16 columns of the…

Continuous Solids-Discharging Centrifugation: A Solution to the Challenges of Clarifying High–Cell-Density Mammalian Cell Cultures

Clarification is typically the first unit operation in the purification of monoclonal antibodies (MAbs) and other proteins from mammalian cell cultures. This process removes cells and cellular debris from the culture fluid to produce a clarified cell culture supernatant that will be suitable for further purification (1). Before 2000, depth and tangential-flow microfiltration were standard clarification technologies in the biopharmaceutical industry. Process-scale centrifugation was considered to be a significant capital investment, and bioprocessors had limited ability to control (minimizing) the…