Erlangen 2018 – wissenschaftliches Programm
MO 2.1: Vortrag
Montag, 5. März 2018, 10:30–10:45, PA 1.150
Repelling and Ordering: The Influence of PEG on Protein Adsorption — •Christoph Bernhard1, Steven J. Roeters2, Johannes Franz1, Tobias Weidner1,2, Mischa Bonn1, and Grazia Gonella1 — 1Max Planck Institute for Polymer Research, Mainz, Germany — 2Aarhus University, Aarhus, Denmark
Nanoparticles and liposomes can be used as versatile drug nanocarriers. Upon injection into the bloodstream a protein layer will immediately coat the nanocarrier surface. This alteration of the surface chemistry can induce changes of the drug carrier properties and interfere with the carrier's targeting mechanism. In order to prevent this non-specific protein adsorption the drug nanocarriers are often coated with a protein repelling PEG layer. However, recently, it has been shown that the adsorption of certain proteins can be beneficial and promote specific cellular uptake. Therefore, a deeper understanding of protein adsorption to PEGylated surfaces is desirable to control the protein corona composition. Here we use mixed lipid monolayers consisting of DMPE and DMPE-PEG2000 as model systems for PEGylated surfaces. We study the influence of interactions between the lipid head groups and the proteins as well as steric repulsion from the PEG chains on the adsorption behavior of bovine serum albumin and fibrinogen. Surface sensitive vibrational sum-frequency generation spectroscopy is used to probe the orientation and structure of the proteins at the lipid/water interface. Our results suggest that an increasing PEG density not only influences the amount of adsorbed proteins, but in the case of Fibrinogen also the ordering at the surface.