title: Surfactant-free Gd(3+)-ion-containing carbon nanotube MRI contrast agents for stem cell labeling.
abstract: There is an ever increasing interest in developing new stem cell therapies. However, imaging and tracking stem cells in vivo after transplantation remains a serious challenge. In this work, we report new, functionalized and high-performance Gd(3+)-ion-containing ultra-short carbon nanotube (US-tube) MRI contrast agent (CA) materials which are highly-water-dispersible (ca. 35 mg ml(-1)) without the need of a surfactant. The new materials have extremely high T1-weighted relaxivities of 90 (mM s)(-1) per Gd(3+) ion at 1.5 T at room temperature and have been used to safely label porcine bone-marrow-derived mesenchymal stem cells for MR imaging. The labeled cells display excellent image contrast in phantom imaging experiments, and TEM images of the labeled cells, in general, reveal small clusters of the CA material located within the cytoplasm with 10(9) Gd(3+) ions per cell.
authors.affiliation: Department of Chemistry, Richard E. Smalley Institute for Nanoscale Science and Technology, Rice University, 6100 Main Street, Houston, TX 77251-1892, USA. durango@rice.edu.
authors.forename: Ayrat
authors.initials: A
authors.lastname: Gizzatov
authors.forename: Mayra
authors.initials: M
authors.lastname: Hernández-Rivera
authors.forename: Vazrik
authors.initials: V
authors.lastname: Keshishian
authors.forename: Yuri
authors.initials: Y
authors.lastname: Mackeyev
authors.forename: Justin J
authors.initials: JJ
authors.lastname: Law
authors.forename: Adem
authors.initials: A
authors.lastname: Guven
authors.forename: Richa
authors.initials: R
authors.lastname: Sethi
authors.forename: Feifei
authors.initials: F
authors.lastname: Qu
authors.forename: Raja
authors.initials: R
authors.lastname: Muthupillai
authors.forename: Maria da Graça
authors.initials: Mda G
authors.lastname: Cabreira-Hansen
authors.forename: James T
authors.initials: JT
authors.lastname: Willerson
authors.forename: Emerson C
authors.initials: EC
authors.lastname: Perin
authors.forename: Qing
authors.initials: Q
authors.lastname: Ma
authors.forename: Robert G
authors.initials: RG
authors.lastname: Bryant
authors.forename: Lon J
authors.initials: LJ
authors.lastname: Wilson
mesh_terms: D000818:Animals; D003287:Contrast Media / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D005682:Gadolinium / Q000737:chemistry / Q000494:pharmacology; D008279:Magnetic Resonance Imaging; D059630:Mesenchymal Stem Cells / Q000166:cytology* / Q000378:metabolism; D037742:Nanotubes, Carbon / Q000737:chemistry*; D013194:Staining and Labeling / Q000379:methods*; D013501:Surface-Active Agents; D013552:Swine
chemical_list: D003287:Contrast Media; D037742:Nanotubes, Carbon; D013501:Surface-Active Agents; D005682:Gadolinium