To regulate interactions at their surfaces, living organisms employ potent physical principles. Now, researchers from the Leibniz Institute of Polymer Research Dresden, Leipzig University, and TU Dresden have figured out why proteins and bacteria can’t stick as well to surfaces with cholesterol.
Carsten Werner and his multidisciplinary team had previously identified cholesterol as a component of the skin of widespread invertebrates (collembolae), which breathe through their skin and must therefore protect it from contamination. The researchers have now identified a repellent mechanism for cholesterol-containing surfaces in their June 22, 2023, paper in Nature.
They were able to demonstrate, through experiments, simulations, and thermodynamic analyses, how a spontaneous shift in the orientation of interfacial cholesterol molecules results in the formation of an “entropic barrier” that repels cholesterol-containing surfaces.
Because it is essential for many products and technologies to effectively minimize the attachment of biomolecules and bacteria, the development of synthetic materials based on the discovered principle is promising. However, additional research is required for this “translation” of the effect into scalable, robust surface functionalization.
More information: Jens Friedrichs et al, Entropic repulsion of cholesterol-containing layers counteracts bioadhesion, Nature (2023). DOI: 10.1038/s41586-023-06033-4
