Radiation damage to a protein solution, detected by synchrotron X-ray small-angle scattering: dose-related considerations and suppression by cryoprotectants
In all synchrotron experiments on biomolecules one has to face radiation damage. In small-angle X-ray scattering experiments at high-brilliant synchrotron sources, protein aggregation results from radiation damage. This paper first describes the quantitative evaluation and understanding of the dose-related phenomena of radiation-induced aggregation that was evident over 400 Gy in the lysozyme solution. Furthermore it was shown that adding small amounts of cryoprotectants in the hundred millimolar concentration range effectively reduced the radiation damage.
S. Kuwamoto, S. Akiyama and T. Fujisawa
![[graph]](https://www.iucr.org/__data/assets/image/0005/18995/12-4_Page_09_Image_0010.jpg)
Dependence of critical dose, a threshold of radiation insensitivity, on the concentrations of glycerol and ethylene glycol. Open and solid circles correspond to the plots for glycerol (148 Gy/s) and ethylene glycol (148 Gy/s), respectively. Beyond 1.0% the aggregation is negligible and critical dose could not be determined.
