By Diane McCarthy, PhD, Senior Scientific Liaison, Global Biologics, US Pharmacopeia
Biotherapeutic products are typically characterized by multiple orthogonal methods to evaluate product quality and purity, including assessment of aggregates, variants, and degradation products. For monoclonal antibodies and many other biotherapeutics, analysis of post-translational modifications, such as glycosylation, are also important since these modifications can impact the efficacy, stability, and safety of the final product. This presentation will provide an overview of methods and standards used during characterization, with an emphasis on monoclonal antibodies.
Followed by Charge Variant Separation Coupled to High Resolution Mass Spectrometry for Routine mAb Analysis
By Dr Kai Scheffler, Product Manager at Thermo Fisher Scientific
Biotherapeutics such as monoclonal antibodies are a heterogeneous mixture of structurally similar molecules that differ in mass and charge, referred to as charge variants. Charge variants result from sequence variations and post-translational modifications such as e.g. deamidation and sialylation resulting in species that are more basic or acidic than the main mAb monomer. The heterogeneity can be revealed by charge-sensitive separation methods, such as ion exchange chromatography. The use of MS-compatible buffers allows for online hyphenation to a mass spectrometer. This hyphenated setup provides the chromatographic resolution of ion exchange chromatography coupled to the identification of the separated variants by mass spectrometry.
In this webinar we will discuss a charge variant analysis (CVA) workflow that entails ion exchange chromatography using pH gradients for protein elution with online mass detection on a high resolution Orbitrap-based mass spectrometer. This workflow enables routine application to a wide range of antibody samples for comprehensive analysis based on a single injection without the need for sample preparation.