Paper Number
FE16 

Session
Foams, Emulsions & Interfacial Rheology

Title
Understanding interfacial structure and flow properties of protein-surfactant systems at the air-water interface

Presentation Date and Time
October 17, 2018 (Wednesday) 4:35

Track / Room
Track 6 / Tanglewood

Authors (Click on name to view author profile)

  1. Tein, Ying-Heng S. (University of Delaware)
  2. Zhang, Michael (University of Delaware)
  3. Liu, Yun (National Institute of Standards and Technology, Center for Neutron Research)
  4. Woys, Ann M. (Genentech Inc, Department of Late Stage Pharmaceutical Development)
  5. Zarraga, Isidro (Genentech Inc, Department of Late Stage Pharmaceutical Development)
  6. Wagner, Norman J. (University of Delaware)

Author and Affiliation Lines (in printed abstract book)
Ying-Heng S. Tein1, Michael Zhang1, Yun Liu2, Ann M. Woys3, Isidro Zarraga3, and Norman J. Wagner1
1University of Delaware, Newark, DE; 2Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD; 3Department of Late Stage Pharmaceutical Development, Genentech Inc, San Francisco, CA

Speaker / Presenter 
Tein, Ying-Heng S.

Text of Abstract
Monoclonal antibodies (mAbs) are important therapeutic agents, but vial shipments of their formulations have posed challenges associated with stability issues due to adsorption of mAbs at the air-water interface, which is thought to be aggregation driven. Formulators add surfactants that are active at the air-water interface, such as polysorbate 20 (PS20) to prevent protein adsorption and to increase protein stability. Because both mAb and surfactant affect the interfacial mechanical properties, it is important to characterize the interface for vial filling, shipment, and drug delivery processes. Furthermore, both apparent shear thinning and elasticity behavior detected in rotational rheometry of pure mAb solutions have been speculated to derive from mAb interfacial activity. For example, Patapoff and Esue used cone-and-plate rheometry to observe a decrease in elasticity with the addition of PS20 in mAb solutions and hypothesized hypothesized that surface active agents “protect” the interface to prevent interfacial activity of mAb. However, only limited interfacial measurements have directly characterized the nanoscale structure of the interface for mAb/PS20 solutions [2]. To test the hypothesis that PS20 stabilizes mAbs by protecting the air-water interface, we directly characterize these solutions through neutron reflectivity, interfacial rheology and surface tensiometry. These results reveal the interfacial viscoelasticity and orientation of the mAb at the air-water interface as well as demonstrate how PS20 effectively prevents mAb adsorption. Additionally, we reflect on future investigations of measuring interfacial dilatational rheology to mimic bubble formations in solution in order to minimize protein instabilities at air-water interfaces. [1] Patapoff, T. W., & Esue, O. (2009). Pharm Dev Technol., 14(6), 659-664. [2] Leiske, D.L., Shieh, I.C., Tse, M.L., (2016), Langmuir 32:9930-9937.