Regensburg 2019 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
CPP: Fachverband Chemische Physik und Polymerphysik
CPP 17: Poster Session I
CPP 17.27: Poster
Monday, April 1, 2019, 17:30–19:30, Poster B1
Heterogeneous dynamics in an arrested state in a protein system — •Anita Girelli1, Nafisa Begam1, Anastasia Ragulskaya1, Hendrik Rahmann2, Fabian Westermeier3, Christian Gutt2, Fajun Zhang1, and Frank Schreiber1 — 1Universität Tübingen, Germany — 2University of Siegen, Germany — 3Petra III,DESY, Germany
In protein solutions, the interplay between LLPS and glass formation can lead to an arrested state. So far, little is known about the dynamic properties of the arrested state. Here we show the collective dynamics using XPCS for a protein-PEG system. The protein employed here is γ-globulin. PEG (polyethylene glycol) permits the attraction between the protein through depletion. The system has a upper critical solution temperature (UCST), and in a previous study the coarsening kinetics after quenching was studied with USAXS and USANS [1]. The results show that the size of the domains remains constant with time at very low temperatures (below glass transition) indicating that the system enters an arrested state. Here we find that the system close to the arrest shows lower relaxation times compared to the one where a complete phase separation occurs. The dynamics in the arrested state shows strong heterogeneity which increases with the quench depth. The results indicate the presence of cooperative domain motion, suggesting that the enhancement of cooperativity leads to the arrest at low temperatures.
Da Vela et al., Soft Matter, 13, 8756, 2017