Bo Claerebout

The structural complexity of monoclonal antibodies (mAbs) challenges the capabilities of even the most advanced chromatography and mass spectrometry techniques. This study examines the use of micro-pillar array columns in combination with mass spectrometry for peptide mapping of both mAbs and antibody–drug conjugates (ADCs).

Monoclonal antibodies are becoming a core aspect of the pharmaceutical industry. Together with a huge therapeutic potential, these molecules come with a structural complexity that drives state-of-the-art chromatography and mass spectrometry (MS) to its limits. This article discusses the use of micro-pillar array columns in combination with mass spectrometry for peptide mapping of monoclonal antibodies (mAbs) and antibodyÐdrug conjugates (ADCs). Micro-pillar array columns are produced by a lithographic etching process creating a perfectly ordered separation bed on a silicon chip. As a result of the order existing in these columns, peak dispersion is minimized and highly efficient peptide maps are generated, providing enormous structural detail. Using examples from the author’s laboratory, the performance of these columns is illustrated.

In the 21st century, numerous advances have been made in liquid chromatography (LC) column technology. The best known are columns packed with sub-2-µm porous particles or sub-3-µm superficially particles, and monolithic columns. Another very novel and original development is micro-pillar array columns (µPAC). µPACs are produced by a lithographic etching process to create a perfectly ordered separation bed on a silicon chip. Although the performance in terms of efficiency has been illustrated, the applicability for analysis of real complex samples has yet to be fully demonstrated. This article illustrates that state‑of‑the‑art µPAC columns coated with octadecyl are applicable for a challenging application such as lipidomics. The performance is illustrated with the analysis of human blood plasma lipids.