Analysis of recombinant monoclonal antibodies by RPLC: toward a generic method development approach

Monoclonal antibodies (mAbs) are an emerging class of therapeutic agents that have recently gained importance. To attain acceptable kinetic performance with mAbs in reversed phase liquid chromatography, there is a need to work with the last generation of wide-pore sub-2 μm fully porous or core-shell particles stationary phases. In addition, temperature in the range 60-90 °C was found to be mandatory to limit adsorption phenomenon of mAbs and their fragments. A generic method development strategy was proposed to account for the selectivity, efficiency, recovery, and the possible thermal degradation. This study also demonstrated that the gradient steepness and temperature cannot be optimized using van't Hoff type linear models. Similarly, the common linear solvent strength model also generated some error in predicting the retention times. In contrast, when quadratic models were employed, the prediction accuracy of retention times was found to be excellent (relative error between 0.5 and 1%) using a reasonable number of experiments (9 or 6 experiments for optimization of gradient time and temperature, which requires between 6 and 8 h). Two separations of mAbs fragments were performed to demonstrate the reliability of the quadratic approach.