Repulsive mess: What makes cholesterol-containing surfaces so repellent?

Living organisms use very effective physical principles to control interactions on their surfaces. Researchers from the Leibniz Institute of Polymer Research Dresden, Leipzig University and TU Dresden have now discovered why the accumulation of proteins and bacteria can be greatly reduced on surfaces containing cholesterol.

The interdisciplinary team led by Carsten Werner had previously identified cholesterol as a component of the skin of widespread invertebrates (collembolans), which breathe through their skin and therefore need to protect it from contamination. In their work published in the journal Nature on 22 June 2023, the scientists have now been able to elucidate a repulsive mechanism of action of cholesterol-containing surfaces. Using experiments, simulations and thermodynamic analyses, they showed how a spontaneous change in the orientation of the cholesterol molecules creates an „entropic barrier“ that makes cholesterol-containing surfaces repellent.

The development of synthetic materials using the discovered principle is promising, as it is important for many products and technologies to effectively minimise the accumulation of biomolecules and bacteria. However, such „ütranslation“ of the effect to scalable, robust surface functionalisation requires further research.

The Leibniz-Institut für Polymerforschung Dresden (IPF) is developing the foundations for new materials and their application in future technologies, with biology-inspired material concepts becoming increasingly important. The Chair of Biophysical Chemistry at Leipzig University works closely with the IPF in the field of biomimetic materials. At the Physics of Life Cluster of Excellence at TU Dresden, basic principles of the functionality of living matter are being explored.

Press release of the "idw - Informationsdienst Wissenschaft" from 22 June 2023