In vivo multicolor molecular MR imaging using diamagnetic chemical exchange saturation transfer liposomes.

TitleIn vivo multicolor molecular MR imaging using diamagnetic chemical exchange saturation transfer liposomes.
Publication TypeJournal Article
Year of Publication2012
AuthorsLiu G, Moake M, Har-el Y-el, Long CM, Chan KWY, Cardona A, Jamil M, Walczak P, Gilad AA, Sgouros G, van Zijl PCM, Bulte JWM, McMahon MT
JournalMagnetic resonance in medicine : official journal of the Society of Magnetic Resonance in Medicine / Society of Magnetic Resonance in Medicine
Volume67
Issue4
Pagination1106-13
Date Published2012 Apr
Abstract

A variety of (super)paramagnetic contrast agents are available for enhanced MR visualization of specific tissues, cells, or molecules. To develop alternative contrast agents without the presence of metal ions, liposomes were developed containing simple bioorganic and biodegradable compounds that produce diamagnetic chemical exchange saturation transfer MR contrast. This diamagnetic chemical exchange saturation transfer contrast is frequency-dependent, allowing the unique generation of "multicolor" images. The contrast can be turned on and off at will, and standard images do not show the presence of these agents. As an example, glycogen, L-arginine, and poly-L-lysine were encapsulated inside liposomes and injected intradermally into mice to image the lymphatic uptake of these liposomes. Using a frequency-dependent acquisition scheme, it is demonstrated that multicolor MRI can differentiate between different contrast particles in vivo following their homing to draining lymph nodes. Being nonmetallic and bioorganic, these diamagnetic chemical exchange saturation transfer liposomes form an attractive novel platform for multicolor imaging in vivo.

DOI10.1007/s12975-011-0110-4
Alternate JournalMagn Reson Med