Evaluation of a new wide-pore superficially porous material with carbon core and nanodiamond-polymer shell for the separation of proteins.

In this study, reversed phase liquid chromatographic columns packed with superficially porous material made of a carbon core and nanodiamond-polymer shell were evaluated for the analytical characterization of proteins. The emphasis was put on the impact of pore size on the kinetic performance when analyzing large molecules. Three different types of columns possessing an average pore size of 120, 180, and 250Å were thus evaluated. As expected, the peak capacities were improved with the 180 and above all the 250Å pore size, while the kinetic performance achieved with the 120Å were systematically lower. It was also shown that a trifluoroacetic acid (TFA) concentration of 0.3-0.5% was required when analyzing proteins, to achieve suitable peak shapes (limited broadening and tailing) with this material. Elevated temperature (>60°C) is mandatory when analyzing proteins with silica-based stationary phases, but this was not the case with this particular column made with a carbon core and nanodiamond-polymer shell, since the peak capacities were not improved at high temperature. However, there was a need to increase mobile phase temperature in the range 70-90°C when analyzing monoclonal antibodies (mAbs), to limit adsorption that often occur in RPLC with this specific class of biomolecules. Finally, the FLARE(®) wide-pore column was applied to real life samples of native, oxidative stressed and reduced therapeutic proteins as well as reduced, digested mAbs and antibody drug conjugates (ADCs), to highlight the possibilities offered by this column technology.