Depth Filtration

The ongoing optimization of cell culture processes leads to growth of the productivity of mammalian cell cultures producing higher cell titers and higher mAb concentrations.

These advances are accompanied by an increasing biomass, including cell debris and other impurities that combine to increase the practical challenges of clarifying these fluids in preparation for downstream purification.

Extensive evaluation of multiple technologies to find a single robust platform that will work well across a wide range of processes, especially those with higher cell densities, is time and fluid intensive.

The selection process becomes more complex when expanding the review to include the scalability of the technology, the simplicity of installation or operation, and ultimately, the economy; including the scale of capital investment required and ongoing consumable costs.

Pall has developed a number of harvesting technologies, the Stax™ mAx depth filter platform and the Stax CF body-feed harvesting platform, which provide options for different process feed conditions. We combine high-performance features with high quality materials and ease of use. This makes our product range the best choice for cell harvesting applications.

The Stax mAx platform is designed to be the go-to option for most commonly encountered cell harvesting conditions. It provides a single-use, robust, depth filtration solution for the economic clarification of cell cultures used in the production of monoclonal antibodies (mAbs), without the need for centrifugation or process additives

The two double-layer depth filtration stages are optimized for cell densities for up to 35 x 10⁶ cells/mL and for culture turbidity of up to ~3000 NTU, and to maintain high capacity as cell density and viability change. This robust performance minimizes the impact of feed stream variations and delivers a wide platform performance that works across a broad range of cell cultures. It delivers high throughput in a small footprint.

Join the 17 other biopharmaceutical companies already using Stax mAx harvesting platform for their large-scale clinical production; launched in October 2017. Dr. Reddy's Laboratories, an Indian multinational pharmaceutical company based in Hyderabad, India, has chosen Stax mAx for multi-mAb harvesting processes:

“The concept has worked well and we would like to continue to evaluate the use of the product for our upcoming R&D projects (mAbs). The performance of both PDP8/PDE2 filters on average has been satisfactory for multiple harvest (5 batches) so far.”

- Dr. Ramakrishnan Ravichandran, Senior Scientist

Where the cell culture characteristics such as extremely high turbidity and cell density lead to an uneconomic, or impractical system sizing using depth filtration alone, the addition of process additives like diatomaceous earth (DE) assists in the removal of biomass and may provide an alternative approach. Such a system would require the accompanying technology for closed DE addition and mixing. 

In those cases, filtration modules with space designed to accumulate filter cake provide an alternative option. Stax CF cake filtration modules use the same easy-to-use Stax platform and are configured to retain up to 13 L of solids per module. This makes them ideally suited to accommodate the high-solid-load content present when using DE.