Pat Sandra | Authors


Denaturing and Native Size-Exclusion Chromatography Coupled to High-Resolution Mass Spectrometry for Detailed Characterization of Monoclonal Antibodies and Antibody–Drug Conjugates

Monoclonal antibodies (mAbs) are being developed at an explosive rate and have attracted great interest from both smaller biotech firms and big pharmaceutical companies. Developing mAbs and next-generation antibody–drug conjugates (ADCs) is highly demanding in many ways. From an analytical perspective, handling mAbs and ADCs presents many new challenges. This article describes how size-exclusion chromatography (SEC) combined with high-resolution mass spectrometry (HRMS) can be applied to the detailed characterization of mAbs and ADCs.

Analyzing Phosphorylated N-Glycans with Full Recovery on Bio-Inert LC Systems and PEEK-Lined HILIC Columns

Glycosylation is a critical quality attribute (CQA) that can impact on product safety and efficacy of protein biopharmaceuticals. Characterization of N-glycans is therefore of paramount importance for the pharmaceutical industry. Hydrophilic interaction liquid chromatography (HILIC) combined with fluorescence detection (FLD) and 2-aminobenzamide (2-AB) labelling is the golden standard for the analysis of N-glycans enzymatically liberated from biopharmaceuticals. However, for phosphorylated N-glycans, that is, those attached on lysosomal enzymes, irreproducible data and recovery issues are observed on conventional liquid chromatography (LC) instrumentation and columns, which can be attributed to the interaction of the phosphate moieties with stainless steel components in the flow path. This article demonstrates the analysis of phosphorylated glycans with full recovery on a bio-inert LC system and PEEK-lined HILIC column.

Peptide Mapping of Monoclonal Antibodies and Antibody–Drug Conjugates Using Micro-Pillar Array Columns Combined with Mass Spectrometry

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).