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Adsorption of Non-Ionic Surfactant and Monoclonal Antibody on Siliconized Surface Studied by Neutron Reflectometry



Zhenhuan Zhang, Ann M. Woys, Kunlun Hong, Christoph Grapentin, Tarik A. Khan, Isidro E. Zarraga, Norman J. Wagner, Yun Liu


The adsorption of monoclonal antibodies (mAbs) on hydrophobic surfaces is known to cause protein aggregation and degradation. Therefore, surfactants, such as Poloxamer 188, are widely used in therapeutic formulations to stabilize mAbs and protect mAbs from interacting with liquid-solid interfaces. Here, the adsorption of Poloxamer 188, one mAb and their competitive adsorption on a model hydrophobic surface is investigated with neutron scattering coupled with contrast variation to determine the molecular structure of the adsorbed layer for each case. Small angle neutron scattering measurements of the affinity of Poloxamer 188 to this mAb indicate that there is negligible binding at these solution conditions. Neutron reflectometry measurements of the mAb show irreversible adsorption on the hydrophobic surface, which cannot be washed off with neat water. Poloxamer 188 can be adsorbed on the surface already occupied by mAb, which enables partial removal of some adsorbed mAb by washing with buffer. The adsorption of the surfactant introduces significant conformational changes for mAb molecules that remain on the surface. In contrast, if the hydrophobic surface is first saturated with the surfactant, no adsorption of mAb is observed. Competitive adsorption of mAb and Poloxamer 188 from solution leads to a surface mostly occupied with surfactant molecules, whereas only a minor amount of mAb absorbs. These findings clearly indicate that Poloxamer 188 can protect against mAb adsorption as well as modify the adsorbed conformation of previously adsorbed mAb.
Journal of Colloid and Interface Science


surface adsorption, siliconized surface, Poloxamer 188, monoclonal antibody, small angle neutron scattering, neutron reflectometry


Zhang, Z. , Woys, A. , Hong, K. , Grapentin, C. , Khan, T. , Zarraga, I. , Wagner, N. and Liu, Y. (2021), Adsorption of Non-Ionic Surfactant and Monoclonal Antibody on Siliconized Surface Studied by Neutron Reflectometry, Journal of Colloid and Interface Science (Accessed April 20, 2024)
Created February 14, 2021, Updated September 9, 2021