Integrated In Situ Measurements to Study Protein Adsorption Behavior at the Polymer-Water Interface

The ongoing challenge of preventing disease transmission underscores the need for materials that reduce pathogen adhesion and proliferation. Medical devices such as catheters are prone to biofilm formation, which is often initiated by protein adsorption. While much is known about protein adsorption on rigid surfaces, significant gaps remain regarding polymer surfaces, where flexibility and mobility add complexity. Our recent ex-situ experimental results showed that protein adsorption within non-charged, hydrophobic homopolymer ultrathin films (less than 20 nm thick) on silicon substrates is almost prohibited, regardless of the choice of polymer [1]. This contrasts with the prevailing concept of the “interfacial water” acting as a “barrier” against protein adsorption. To elucidate the mechanism underlying the protein adsorption at the polymer-water interface, a series of in situ techniques including neutron reflectivity, quartz crystal microbalance, and atomic force microscopy techniques were combined. Supported polystyrene thin films ranging in thickness ranging from 2 to 100 nm, bovine serum albumin, and human plasma fibrinogen were used as rational systems. Details will be discussed in the presentation.

1. Salatto D. et al. Macromolecules 2020 53, 6547.