Discretized multi-level elution trajectory: A proof-of-concept demonstration

Area of Science:

• Biochemical Engineering
• Separation Science
• Process Optimization

Background:

• Chromatographic separation is crucial for biomolecular and pharmaceutical downstream processing, but faces challenges of high costs and low capacity.
• Optimizing separation processes is essential to minimize costs while maintaining high product purity.

Purpose of the Study:

• To experimentally validate a discretized multi-level elution (DiME) trajectory for protein separation.
• To demonstrate the application of mechanistic modeling, optimization, and control for realizing DiME trajectories.

Main Methods:

• A mechanistic model was developed and calibrated using experimental data for tertiary protein separation (ribonuclease A, cytochrome C, lysozyme).
• Dynamic optimization was performed to maximize cytochrome C yield under specific purity and time constraints.
• The optimal elution trajectory was implemented on commercial chromatography equipment (ÄKTA Pure) via an OPC interface.

Main Results:

• The study successfully demonstrated the experimental realization of DiME trajectories on available chromatography systems.
• Model calibration and dynamic optimization were effective in determining an optimal salt concentration trajectory.
• In-line and off-line analyses confirmed the successful separation and purity of the target protein.

Conclusions:

• Discretized multi-level elution (DiME) trajectories can be successfully implemented experimentally.
• Model-based calibration, optimization, and control provide a robust framework for optimizing chromatography separations.
• This approach offers a pathway to cost-effective and high-purity downstream processing for various biomolecules.