Jens T. Rosenberg1, 2, Micheal L. Matson3, 4, Brandon T. Cisneros3, Michelle Sokoll2, Fabian Calixo-Bejarano1, Lon J. Wilson3, Samuel Colles Grant1, 2
1Center for Interdisciplinary Magnetic Resonance, The National High Magnetic Field Laboratory, Tallahassee, FL, United States; 2Chemical & Biomedical Engineering, The Florida State University, Tallahassee, FL, United States; 3Department of Chemistry and The Smalley Institute for Nanoscale Science and Technology, Rice University, Houston, TX, United States; 4Natural Sciences, University of Houston-Downtown, Houston, TX, United States
Ultra-short, singled walled carbon nanotubes (US-tubes) that encapsulate gadolinium (Gd) have shown MRI cell tracking capabilities. Their biocompatibility together with a hollow interior and potentially beneficial water access are factors of interest especially at high magnetic fields. In this study, Gd-doped US-tubes are compared to a high field optimized, dysprosium (Dy) variant. Results suggest that doped US-tubes in solution follow theoretical field-dependent changes in relaxation for the two lanthanides. Once incorporated into cells, T1 contrast is quenched while T2 and T2* contrast dominates. Dy-doped US-tubes have overall shorter transverse relaxation times and compares favorably to other Dy-based agents.