Maja Clare Cassidy1, Jacob W. Aptekar2, Menyoung Lee2, Ronald L. Walsworth2,3, Charles M. Marcus2
1School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA; 2Department of Physics, Harvard University, Cambridge, MA, USA; 3Harvard-Smithsonian Center for Astrophysics, Cambridge, MA, USA
Silicon based nanoparticles offer promise as biologically targeted magnetic resonance imaging (MRI) agents based on their exceptional NMR properties, receptivity to hyperpolarization, and diverse functionalization chemistry. Specifically, the long room temperature nuclear relaxation (T1) times of crystalline silicon nanoparticles makes them suitable candidates as ex-vivo polarized imaging agents. We present results on low temperature dynamic nuclear polarization of silicon and silicon-based nanoparticles of a variety of sizes, morphologies and fabrication methods. We will also discuss requirements for transporting pre-polarized particles, and mechanisms for imaging the hyperpolarized nanoparticles in-vivo.