TY - CONF AU - Niether, Doreen AU - Sarter, Mona AU - König, Bernd AU - Fitter, Jörg AU - Stadler, Andreas AU - Wiegand, Simone TI - Thermophoresis: The Case of Streptavidin and Biotin M1 - FZJ-2020-05213 PY - 2020 AB - Thermophoretic behavior of a free protein changes upon ligand binding and gives access to information on the binding constants. The Soret effect has also been proven to be a promising tool to gain information on the hydration layer, as the temperature dependence of the thermodiffusion behavior is sensitive to solute-solvent interactions [1]. In this work, we perform systematic thermophoretic measurements of the protein streptavidin (STV) and of the complex STV with biotin (B) using thermal diffusion forced Rayleigh scattering (TDFRS) [2]. Our experiments show that the temperature sensitivity of the Soret coefficient is reduced for the complex compared to the free protein. We discuss our data in comparison with recent quasi-elastic neutron scattering (QENS) measurements. As the QENS measurement has been performed in heavy water, we perform additional measurements in water/heavy water mixtures. Finally, we also elucidate the challenges arising from the quantiative thermophoretic study of complex multicomponent systems such as protein solutions. References[1] “Thermophoresis of biological and biocompatible compounds in aqueous solution”; Niether, D; Wiegand, S.; J. Phys. Condens. Matter, 31, 503003, (2019). DOI: 10.1088/1361-648X/ab421c[2] “Thermophoresis: The Case of Streptavidin and Biotin”; Niether, D; Sarter, M; Koenig, B.W. et al; Polymers, 12, 376, (2020). DOI: 10.3390/polym12020376. T2 - 2020 EUSMI User Meeting CY - 19 Nov 2020 - 19 Nov 2020, virtual conference (Germany) Y2 - 19 Nov 2020 - 19 Nov 2020 M2 - virtual conference, Germany LB - PUB:(DE-HGF)6 UR - https://juser.fz-juelich.de/record/888784 ER -