Abstract
Neutrons have historically been used for a broad range of biological applications employing techniques such as small-angle neutron scattering, neutron spin echo, diffraction, and inelastic scattering. Unlike neutron scattering techniques that obtain information in reciprocal space, attenuation-based neutron imaging measures a signal in real space that is resolved on the order of tens of micrometers. The principle of neutron imaging follows the Beer-Lambert law and is based on the measurement of the bulk neutron attenuation through a sample. Greater attenuation is exhibited by some light elements (most notably, hydrogen), which are major components of biological samples. Contrast agents such as deuterium, gadolinium, or lithium compounds can be used to enhance contrast in a similar fashion as it is done in medical imaging, including techniques such as optical imaging, magnetic resonance imaging, X-ray, and positron emission tomography. For biological systems, neutron radiography and computed tomography have increasingly been used to investigate the complexity of the underground plant root network, its interaction with soils, and the dynamics of water flux in situ. Moreover, efforts to understand contrast details in animal samples, such as soft tissues and bones, have been explored. This manuscript focuses on the advances in neutron bioimaging such as sample preparation, instrumentation, data acquisition strategy, and data analysis using the High Flux Isotope Reactor CG-1D neutron imaging beamline. The aforementioned capabilities will be illustrated using a selection of examples in plant physiology (herbaceous plant/root/soil system) and biomedical applications (rat femur and mouse lung).
Original language | English |
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Article number | e61688 |
Journal | Journal of Visualized Experiments |
Volume | 2021 |
Issue number | 171 |
DOIs | |
State | Published - 2021 |
Funding
Part of this research utilized resources at the High Flux Isotope Reactor, operated by ORNL, and sponsored by the U.S. Department of Energy, Office of Science, User Facilities, under contract DE-AC05-00OR22725 with UT-Battelle, LLC. Part of this research was supported by ORNL through the Eugene Wigner Distinguished Staff Fellowship program. This research was also sponsored by the DOE Office of Science, Office of Biological and Environmental Research. Rat femoral samples were obtained from experiments performed in collaboration with Dr. Rick Sumner at Rush University Medical Center with funding obtained from the NIH (R01AR066562) and from the Orthopedic Research and Education Foundation-Smith and Nephew award. The team wants to thank the HFIR support teams that enable the use of the neutron scattering beamlines.