Samuel Grant, Ph.D.

Magnetic Resonance Imaging and Spectroscopy are extremely powerful analytical methods that provide not only high information content but are non-invasive and non-destructive to the sample under analysis.

My research laboratory is focused on the development of high resolution techniques to investigate the biophysical origins of MR signals under a variety of perturbations. We utilize high magnetic fields to achieve high sensitivity and spatial/ spectral resolution on specimen ranging from single isolated neurons to fixed neurological tissues (brains and spinal cords) to in vivo animal models. Our close affiliation with the National High Magnetic Field Laboratory provides access to the highest magnetic fields in the world, including the one-of-a-kind ultrawide bore 21.1-T system for MR imaging and spectroscopy.

In particular, we employ high fields MR microscopy to examine neurodegenerative diseases such as amyotrophic lateral sclerosis, Alzheimer's disease and stroke. In collaboration with neurologists, clinicians and biologists, we make use of genetic, toxic and surgical models to identify biomarkers of disease progression that might have diagnostic or therapeutic value clinically. Furthermore, we evaluate potential treatments (e.g. stem cell and drug therapy) with MR techniques in order to judge their efficacy in restoring normal cellular function.

MR microscopy also lends itself to the study of biomaterials and bioartificial devices. Because it is non-destructive, MR techniques can be utilized to analyze engineered constructs during their in vitro development to map growth patterns and cell-material interactions. Following implantation, constructs can be monitored in vivo to assess immunoresponse, mechanical integrity and integration into existing bioprocesses. Throughout this continuum, MR microscopy provides information about the biomaterial substrate, cellular component and functionality of these engineered constructs.

To make the most of high field MR techniques in these evaluations, my laboratory is actively involved in MR sequence development, modeling of cellular compartmentalization & function and Radio Frequency coil design. In addition, we are interrogating new and emerging contrast mechanisms at high field. These efforts include endogenous (e.g. magnetic susceptibility and dipolar fields) and exogenous (e.g. nanoparticle agents and current density imaging) contrasts that may provide new insights into the biophysical changes that occur during pathology or regeneration.