Monoclonal Antibody Adsorption at Fluid-Fluid Interfaces: Experimental and Computational Approaches for Interfacial...

Monoclonal antibodies (mAbs) frequently encounter fluid-fluid interfaces, such as air-water and oil-water boundaries, during manufacturing, storage, and administration, where adsorp-tion can trigger structural perturbations, aggregation, and loss of efficacy. Despite extensive experimental and computational efforts, a unified understanding that connects molecular-scale mechanisms to macroscopic interfacial behavior remains incomplete. In this review, we provide a comprehensive and up-to-date synthesis of mAb adsorption at fluid-fluid interfaces, with a par-ticular emphasis on the underlying mechanisms, adsorption kinetics, impacts of surfactants and key physicochemical factors governing interfacial behavior. We critically examine experimen-tal approaches spanning macroscopic measurements-such as interfacial tension and interfacial rheology-to microstructural characterization techniques, including spectroscopy, neutron and X-ray reflectometry, that probe interfacial layer structure and organization. we also highlight recent advances in molecular simulations that provide mechanistic insight into adsorption path-ways, orientation, and structural rearrangements of mAbs at hydrophobic interfaces. We further discuss how these insights can inform rational strategies to mitigate interfacial instability and improve the design and formulation of therapeutic proteins.