Systematic Interpolation Method Predicts Antibody Monomer-Dimer Separation by Gradient Elution Chromatography at High...

Area of Science:

• Biochemistry
• Chemical Engineering
• Chromatography

Background:

• Predicting multicomponent elution behavior in chromatography is crucial for process optimization.
• Existing mechanistic models can be complex and data-intensive.
• Empirical methods offer a potentially simpler alternative for predicting complex separations.

Purpose of the Study:

• To extend the empirical interpolation (EI) method for predicting highly overloaded multicomponent elution on cation exchange (CEX) columns.
• To validate the EI method using experimental data for monoclonal antibody monomer and dimer separation.
• To assess the applicability of the EI method for protein loads up to 40 mg/mL.

Main Methods:

• Utilized an empirically modified multicomponent Langmuir equation to correlate two-component adsorption isotherm data at varying salt concentrations.
• Employed piecewise cubic interpolating polynomials to predict competitive binding at intermediate salt concentrations.
• Integrated the interpolated isotherms with a lumped kinetic model to simulate column behavior under overloaded conditions.

Main Results:

• The EI method accurately predicted elution behavior for highly overloaded conditions.
• Experimental elution curves for monoclonal antibody monomer and dimer mixtures showed good agreement with EI predictions.
• The method demonstrated reliable predictions for protein loads up to 40 mg/mL, approximately 50% of column binding capacity.

Conclusions:

• The extended EI method provides a robust approach for predicting multicomponent elution in CEX chromatography, even under highly overloaded conditions.
• This empirical approach simplifies the prediction of complex chromatographic separations.
• The methodology is potentially extensible to other chromatographic modalities and systems with more than two components.