Continuous precipitation for monoclonal antibody capture using countercurrent washing by microfiltration

Area of Science:

• Biotechnology
• Chemical Engineering
• Bioprocessing

Background:

• Renewed interest in precipitation for therapeutic protein capture in continuous downstream processes.
• High product titers in cell culture facilitate precipitation, unlike chromatography.
• Current methods lack efficient, integrated continuous precipitation solutions.

Purpose of the Study:

• To develop and evaluate a fully continuous integrated precipitation process for initial monoclonal antibody capture.
• To assess the use of reversible cross-linking and volume exclusion agents for precipitation.
• To investigate continuous dewatering, washing, and host cell protein removal.

Main Methods:

• Utilized zinc chloride (ZnCl2) for reversible cross-linking and polyethylene glycol (PEG) for volume exclusion.
• Employed a continuous tubular precipitation reactor for antibody precipitation.
• Integrated tangential flow filtration (TFF) with a countercurrent-staged configuration for dewatering and washing.
• Operated membrane modules below critical flux to prevent fouling for long-term stability.

Main Results:

• Demonstrated feasibility of a fully continuous integrated precipitation process at bench scale.
• Achieved efficient dewatering and washing, enhancing host cell protein removal.
• Maintained long-term operation by controlling membrane flux to avoid fouling.
• Identified key factors influencing system performance through design calculations.

Conclusions:

• The developed continuous precipitation process is a viable method for initial therapeutic protein capture.
• Integration of precipitation, dewatering, and washing offers an efficient downstream solution.
• The process is scalable and adaptable for industrial biopharmaceutical manufacturing.