Abstracts Book - IMRC 2018

• SB2-P011
VERTICAL NANOWIRES ENHANCED X-RAY RADIATION DAMAGE
OF CELLS
Qingxuan Li 1 , Liyuan Zheng 1 , Ming Su 1
1 Northeastern University, Chemical Engineering, United States.
Cell behavior is affected by nanostructured surface, but it remains unknown
how ionizing radiation affects cells on nanostructured surface. This paper
reports an experiment investigation of X-ray radiation induced damage of cells
placed on an array of vertically aligned silicon nanowires. X-ray photoelectrons
and secondary electrons produced nanowire array are measured and compared
to those flat silicon substrate. The cell functions including morphology, viability,
adhesion and proliferation have been examined and found to be drastically
affected when cells are exposed to X-ray radiation, compared to those sitting on
flat substrate and those only exposed to X-ray. The enhanced cell damage on
nanowires upon X-ray exposure is attributed to nanowire enhanced production
of photoelectrons including Auger electrons and secondary electrons, which
have high escaping probability sharp tips of nanowires. The escaped
photoelectrons ionize water molecules and generate hydroxyl free radicals that
can damage DNAs of cells. An inference of this work is that the contrast in
scanning electron microscopy is useful in assessing the effects of nanomaterials
for enhanced X-ray radiation therapy.
Acknowledgment:
This project was supported by a Director’s New Innovator Award National
Institute of Health (1DP2EB016572).
Keywords: Silicon nanowire array, Edge enhancement, Cell damage
Presenting authors email: li.qi@husky.neu.edu