Open AccessRaster microdiffraction with synchrotron radiation of hydrated biopolymers with nanometre step‐resolution: case study of starch granules
Author(s) -
Riekel C.,
Burghammer M.,
Davies R. J.,
Di Cola E.,
König C.,
Lemke H.T.,
Putaux J.L.,
Schöder S.
Publication year - 2010
Publication title -
journal of synchrotron radiation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.172
H-Index - 99
ISSN - 1600-5775
DOI - 10.1107/s0909049510028335
Subject(s) - radiation damage , synchrotron radiation , materials science , radiation , nanometre , starch , crystallinity , irradiation , optics , raster scan , chemistry , composite material , physics , nuclear physics , biochemistry
X‐ray radiation damage propagation is explored for hydrated starch granules in order to reduce the step resolution in raster‐microdiffraction experiments to the nanometre range. Radiation damage was induced by synchrotron radiation microbeams of 5, 1 and 0.3 µm size with ∼0.1 nm wavelength in B‐type potato, Canna edulis and Phajus grandifolius starch granules. A total loss of crystallinity of granules immersed in water was found at a dose of ∼1.3 photons nm −3 . The temperature dependence of radiation damage suggests that primary radiation damage prevails up to about 120 K while secondary radiation damage becomes effective at higher temperatures. Primary radiation damage remains confined to the beam track at 100 K. Propagation of radiation damage beyond the beam track at room temperature is assumed to be due to reactive species generated principally by water radiolysis induced by photoelectrons. By careful dose selection during data collection, raster scans with 500 nm step‐resolution could be performed for granules immersed in water.