Scientific Opportunities: Life Sciences
Biological and Medical Imaging
Synchrotron facilities worldwide, including the NSLS, demonstrate the value of using a synchrotron for biological and medical imaging. Information that could once be obtained only on pure, spatially homogeneous samples is now obtained from heterogeneous natural and complex biological samples on length scales of tens of nanometers. NSLS-II will extend this to less than 10 nm, enabling studies of nanoscale phases and compositional variations and providing deeper insight into nature (see figure).
With NSLS-II, the spatial resolution of X-ray microprobes and DEI will be reduced to below 1 m. This spatial resolution will enable the imaging of plant and animal tissues on the sub-cellular level, and importantly, in their natural state.
Imaging Molecular Machines
For example, one problem in cellular biology is the way the mammalian cell packages its genetic material under different conditions, such as how the organization of genetic material is different in the sperm cell than other cells. The ability to image hidden abnormalities in the composition of sperm nuclei is important in order to understand how the morphology of the sperm cell affects male fertility. Recently, X-ray microscopy was introduced for the evaluation of a single sperm (see figure). Sperm have a size in the 1-2 micron range, and the structures of interest are typically 30 nm. The high brightness of NSLS-II will improve the resolution of sperm imaging to 10 nm. NSLS-II will also enable higher resolution for imaging whole cells, which promises to be a remarkably fertile line of research.
Fundamental Basis of Disease
Current limitations for X-ray imaging of neuritic plaques, for example, include spatial resolution and beamtime availability. Although many neuritic plaques are large (50-200 microns in diameter), others are much smaller and more diffuse. The higher brightness and coherence of NSLS-II, including increased insertion device capacity, will enable X-ray analysis at below 1 micron resolution, even down to 70-100 nm resolution. NSLS-II will also allow lengthy in-vivo studies to track disease progression and the evolution of pathology during the treatment of neurodegenerative diseases.
Early Disease Detection
Diffraction enhanced imaging (DEI), a technique developed at the NSLS, is advantageous for mammography because it provides increased sensitivity to soft-tissue contrast. The figure shows images of breast tissue with invasive lobular carcinoma that extends to the edge. It illustrates the improved visualization of spiculations representing tumor extension by DEI, compared to standard radiographs. DEI breast images are currently limited to a spatial resolution of about fifty microns and it is important to visualize smaller calcifications and small spiculations. NSLS-II will provide a major advance by extending this to below one micron, and will enable study of the cancer biology and morphological features of animal models of breast cancer and other cancers that are typically too small to be reliably detected by the current DEI resolution.
Last Modified: May 2, 2014