Skip to main content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.


The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Adsorption of Polysorbate 20 and Proteins on Hydrophobic Polystyrene Surfaces Studied by Neutron Reflectometry



Zhenhuan NMN Zhang, Sara V Orski, Ann Marie Woys, Guangcui NMN Yuan, Isidro E. Zarraga, Norman J. Wagner, Yun Liu


Understanding adsorption of protein and surfactant to hydrophobic surfaces is key for storage stability and delivery of pharmaceutical liquid formulations, because many commonly-used devices, such as drug containers and syringes, have product-containing surfaces that are hydrophobic. Neutron reflectometry provides quantitative molecular insight into the adsorption process for a non-ionic surfactant (polysorbate 20), a monoclonal antibody (mAb), and a global protein (lysozyme). Thickness of polystyrene-adsorbed polysorbate 20 is ~21 {angstrom}, comparable to the dyration radius of polysorbate 20 micelles in solution. Although lysozyme does not interact with the polystyrene surface in low solution pH condition, the mAb adsorbed apparently, resulting in layer thickness of ~145 {angstrom} and surface conentration of 135 mg/ml. Our results emphasize vast differences in protein-interaction with a hydrophobic surface.
Colloids and Surfaces B-Biointerfaces


Polysorbate 20, monoclonal antibody, surface adsorption, neutron reflectometry
Created April 21, 2018, Updated November 19, 2018