| AVS 64th International Symposium & Exhibition | |
| Biomaterial Interfaces Division | Tuesday Sessions |
| Session BI-TuP |
| Session: | Biomaterial Interfaces Poster Session with Flash presentations |
| Presenter: | Laila Moreno-Ostertag, MPI for Iron Research, Germany |
| Authors: | C. Klinger, TU Bergakademie Freiberg, Germany L. Moreno-Ostertag, MPI for Iron Research, Germany C. Weber, TU Bergakademie Freiberg, Germany P. Schiller, TU Bergakademie Freiberg, Germany M. Valtiner, TU Bergakademie Freiberg, Germany |
| Correspondent: | Click to Email |
Unraveling the complexity of the macroscopic world relies on understanding single molecule interactions and their scaling towards integral interactions at the meso- and macroscopic scale [1]. Here, I will discuss how one can measure the interaction free energy of single interacting functional groups at various solid/liquid interfaces. The adhesion between single molecules and surfaces in electrolytes is a central point regarding many biological systems and the delamination of coatings.
Single molecule force spectroscopy with an AFM is a suitable tool for measuring the work and force needed to unbind single molecules. The relation between the work of non-equilibrium trajectories and the free energy of interaction can be described by Jarzynskis equation [2]. So the surface-to-molecule bond rupture can in principle be characterized fully, but systematic errors arises. First, we will discuss how the effect of contour length of typically utilized molecular linkers such as PEG potentially adds a systematic bias on the free energy determined from AFM experiments. Secondly, also experiments with varying speed of the force runs were realized and the bias due to increasing rates (i.e. further shift from the equilibrium situation), which will be discussed in this contribution.
Finally, we will discuss in detail how single molecule unbinding energy landscapes can be utilized to predict scenarios where a large number of molecules simultaneously interact, giving rise to adhesive failure under corrosive and wet conditions. As such, our experimental strategy provides a unique framework for the molecular design of novel functional coatings through predicting of large-scale properties such as adhesion and molecular interactions in various systems based on experimentally determined single molecule energy landscapes.
[1] T. Utzig, S. Raman, and M. Valtiner, Langmuir 31, 2722-2729 (2015)
[2] S. Raman, T. Utzig, T. Baimpos, B. R. Shrestha, and M. Valtiner, Nat. Commun. 5, 5539 (2014)