In vitro cellular labeling of magnetic nanotubes for magnetic resonance imaging

INOR 498

Xia Bai, xbai@umd.edu1, Sang Jun Son1, Shixiong Zhang2, Wei Liu3, Elaine K Jordan4, Joseph A. Frank, jafrank@helix.nih.gov4, Thirumalai Venkatesan2, and Sang Bok Lee, slee@umd.edu5. (1) Department of Chemistry & Biochemistry, University of Maryland, College Park, MD 20742, (2) Center for Superconductivity Research, University of Maryland College Park, College Park, MD 20742, (3) Clinical Sites Research Program, Philips Research North America, 345 Scarborough Road, Briarcliff Manor, NY 10510, (4) Laboratory of Diagnostic Radiology Research, National Institute of Health, Clinical Center, Building 10, B1N256, Bethesda, MD 20892, (5) Department of Chemistry and Biochemistry, University of Maryland, Chemistry Building, College Park, MD 20742
Superparamagnetic nanotubes (MNTs) can provide a novel application as magnetic resonance imaging contrast agent via in vitro and in vivo cell labeling, and potentially image-guided drug delivery due to their unique physicochemical properties. There are several advantages of this structure, such as easy modification with well-established silane chemistry, separation and purification, and biocompatibility. Moreover, the nanotubes have well-controlled dimensions and allow for differential modification of inner and outer surfaces. MNTs with high saturation magnetization were synthesized by coating the inside surface of silica nanotubes with superparamagnetic nanocrystalline iron oxide generated by reflux of iron precursor in propane diol. The superparamagnetic nanotubes were characterized by electron microscopies, superconducting quantum interference device, and magnetic resonance scanner. The MNTs show remarkably high spin-spin relaxivity as well as the ratios of the spin-spin and spin-lattice magnetic resonance relaxivities of water protons in MNT dispersions, which ranked them one of the top T2 contrast agents. Preliminary studies on in vitro cell labeling show promising results with labeling efficiency about 70%. No significant cellular toxicity was observed in vitro.
 

Nanoscience - Characterization and Applications
9:00 AM-1:00 PM, Tuesday, April 8, 2008 Morial Convention Center -- Rm. 219, Oral

Division of Inorganic Chemistry

The 235th ACS National Meeting, New Orleans, LA, April 6-10, 2008