Disulfide Bond Characterization of Monoclonal Antibody (mAb) Using Q-TOF Mass Spectrometer

Introduction

Monoclonal antibody (mAb) is emerging as the fastestgrowing category of biotherapeutics with a wide range of therapeutic and diagnostic applications. Higher-order structure of mAb plays a critical role in the efficacy and safety. For example, the number of disulfide bonds and their positions are critical quality attributes (CQAs) for mAb, because incorrect disulfide linkage formation can cause a loss of biological activity or even can elicit an immune response from the host. Herein, we report a LCMS-based method to precisely characterize disulfide bonds in mAb biosimilar by a comparative analysis of non-reduced and reduced conditions. The method uses ProteaseMAX™ surfactant to denature the protein, and trypsin to digest with/without reduction and alkylation. The peptides were gradient-eluted and analyzed using a Shimadzu LCMSTM-9030 Q-TOF mass spectrometer for MS scan and MS/MS analysis.

February 4, 2020 GMT