% IMPORTANT: The following is UTF-8 encoded. This means that in the presence % of non-ASCII characters, it will not work with BibTeX 0.99 or older. % Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or % “biber”. @ARTICLE{Timmermann:587504, author = {Timmermann, Sonja and Anthuparambil, Nimmi Das and Girelli, Anita and Begam, Nafisa and Kowalski, Marvin and Retzbach, Sebastian and Senft, Maximilian Darius and Akhundzadeh, Mohammad Sayed and Poggemann, Hanna-Friederike and Moron, Marc and Hiremath, Anusha and Gutmüller, Dennis and Dargasz, Michelle and Öztuerk, Özguel and Paulus, Michael and Westermeier, Fabian and Sprung, Michael and Ragulskaya, Anastasia and Zhang, Fajun and Schreiber, Frank and Gutt, Christian}, title = {{X}-ray driven and intrinsic dynamics in protein gels}, journal = {Scientific reports}, volume = {13}, number = {1}, issn = {2045-2322}, address = {[London]}, publisher = {Macmillan Publishers Limited, part of Springer Nature}, reportid = {PUBDB-2023-04342}, pages = {11048}, year = {2023}, abstract = {We use X-ray photon correlation spectroscopy to investigate how structure and dynamics of egg white protein gels are affected by X-ray dose and dose rate. We find that both, changes in structure and beam-induced dynamics, depend on the viscoelastic properties of the gels with soft gels prepared at low temperatures being more sensitive to beam-induced effects. Soft gels can be fluidized by X-ray doses of a few kGy with a crossover from stress relaxation dynamics (Kohlrausch-Williams-Watts exponents $k \approx 1.5-2$) to typical dynamical heterogeneous behavior ($k<$1) while the high temperature egg white gels are radiation-stable up to doses of 15 kGy with $k\geq 1.5 $. For all gel samples we observe a crossover from equilibrium dynamics to beam induced motion upon increasing X-ray fluence and determine the resulting fluence threshold values $\Phi_D$. Surprisingly small threshold values of $\Phi_D=(3 \pm 2)\times10^{-3} \:\mathrm{ph\:s^{-1}\:nm^{-2}} $ can drive the dynamics in the soft gels while for stronger gels this threshold is increased to $\Phi_D=(0.9 \pm 0.3) \:\mathrm{ph\:s^{-1}\:nm^{-2}}$. We explain our observations with the viscoelastic properties of the materials and can connect the threshold dose for structural beam damage with the dynamic properties of beam-induced motion. Our results suggest that soft viscoelastic materials can display pronounced X-ray driven motion even for low X-ray fluences. This induced motion is not detectable by static scattering as it appears at dose values well below the static damage threshold. We show that intrinsic sample dynamics can be separated from X-ray driven motion by measuring the fluence dependence of the dynamical properties.}, cin = {DOOR ; HAS-User / FS-PET-S}, ddc = {600}, cid = {I:(DE-H253)HAS-User-20120731 / I:(DE-H253)FS-PET-S-20190712}, pnm = {633 - Life Sciences – Building Blocks of Life: Structure and Function (POF4-633) / 6G3 - PETRA III (DESY) (POF4-6G3) / FS-Proposal: II-20210008 (II-20210008) / FS-Proposal: I-20211600 (I-20211600) / FS-Proposal: I-20210097 (I-20210097) / 05K19PS1 - Instrumentierung, um die Dynamik von biologischen Proben mit Korrelationsspektroskopie zu messen. (BMBF-05K19PS1) / 05K20PSA - Verbundprojekt 05K2020 - 2019-06075 Protein-Dyn: Dynamik von Proteinen in Lösungen auf multiplen Längen und Zeitskalen (Teilprojekt 1) (BMBF-05K20PSA) / 05K22PS1 - Schnelle Korrelationsspektroskopie an der ESRF-EBS (BMBF-05K22PS1) / DFG project 390677874 - EXC 2033: RESOLV (Ruhr Explores Solvation) (390677874)}, pid = {G:(DE-HGF)POF4-633 / G:(DE-HGF)POF4-6G3 / G:(DE-H253)II-20210008 / G:(DE-H253)I-20211600 / G:(DE-H253)I-20210097 / G:(DE-Ds200)BMBF-05K19PS1 / G:(DE-Ds200)BMBF-05K20PSA / G:(DE-Ds200)BMBF-05K22PS1 / G:(GEPRIS)390677874}, experiment = {EXP:(DE-H253)P-P10-20150101}, typ = {PUB:(DE-HGF)16}, pubmed = {37422480}, UT = {WOS:001026178300017}, doi = {10.1038/s41598-023-38059-z}, url = {https://bib-pubdb1.desy.de/record/587504}, }