High recoveries from IEX analysis of mAbs with the first injection – no preconditioning required!

Ion exchange chromatography (IEX) is one of the standard methods for the characterisation of charge-sensitive biomolecules such as monoclonal antibodies (mAbs). Typically, bioinert polyether ether ketone (PEEK) is used for the column hardware.

Using bioinert coated stainless steel column hardware is an alternative approach because the bioinert coating has different surface properties. For example, the bioinert coating on YMC Accura columns is less hydrophobic compared to PEEK.

The influence can be demonstrated when analysing bevacizumab. For this purpose, a standard PEEK column and a bioinert coated YMC Accura BioPro IEX SF column were used. Detailed chromatographic conditions can be found in Table 1. Since preconditioning is usually required for complete recovery, consecutive injections of 25 μg (5 μL) of bevacizumab were performed on both columns (see Figure 1).