Multilevel Characterization of a Chemoenzymatic Conjugated ADC by icIEF-UV/MS and RP-HPLC-MS EAD Fragmentation Peptide Map.

This study focuses on multilevel characterization of a chemoenzymatic conjugated adc by icief-uv/ms and rp-hplc-ms ead fragmentation peptide map.. The research employs high-performance liquid chromatography (HPLC) techniques to address analytical challenges in the biopharmaceutical field. This study includes the synthesis of monomethyl auristatin E (MMAE) payload conjugated Trastuzumab (TRA) by an enzyme-mediated glycan-remodelling reaction, followed by comprehensive multilevel characterization of conjugation end products. Intact proteoforms of TRA and TRA-MMAE antibody-drug conjugates (ADC) were separated, quantitated, and identified by microfluidic chip-based ultraviolet imaged channel isoelectric focusing... Research Background and Significance Antibody-drug conjugates (ADCs) have emerged as a pivotal class of targeted therapeutics in oncology, combining the specificity of monoclonal antibodies with the cytotoxic potency of small-molecule drugs. The chemoenzymatic conjugation approach, particularly enzyme-mediated glycan remodeling, enables site-specific payload attachment, improving homogeneity and therapeutic indices of ADCs. This paper by Mack et al. (2026) addresses the critical need for comprehensive analytical characterization of such chemoenzymatically conjugated ADCs. By integrating advanced chromatographic and mass spectrometric techniques, the study provides a multilevel characterization framework that captures molecular heterogeneity from intact proteoforms to peptide-level details. This level of characterization is essential for ensuring product quality, safety, and efficacy in biopharmaceutical development, aligning with regulatory expectations for ADCs. Experimental Design and Methodology The research utilizes a combination of microfluidic chip-based ul