title: Quantification of the plasma clearance kinetics of a gadolinium-based contrast agent by photoinduced triplet harvesting.
abstract: The use of gadolinium-based contrast agents (GBCA) is integral to the field of diagnostic magnetic resonance imaging (MRI). Pharmacokinetic evaluation of the plasma clearance of GBCA is required for all new agents or improved formulations, to address concerns over toxicity or unforeseen side effects. Current methods to measure GBCA in plasma lack either a rapid readout or the sensitivity to measure small samples or require extensive processing of plasma, all obstacles in the development and characterization of new GBCA. Here, we quantify the plasma concentration of a labeled analogue of a common clinical GBCA by ligand triplet harvesting and energy transfer. The nonemittive GBCA becomes a "dark donor" to a fluorescent detector molecule, with a lower limit of detection of 10(-7) M in unprocessed plasma. On a time scale of minutes, we determine the plasma clearance rate in the wild-type mouse, using time-resolved fluorescence on a standard laboratory plate reader.
authors.affiliation: Department of Medicine, New York University School of Medicine, New York, New York, USA. srussell2@ccny.cuny.edu
authors.forename: Stewart
authors.initials: S
authors.lastname: Russell
authors.forename: Ryan
authors.initials: R
authors.lastname: Casey
authors.forename: Dung M
authors.initials: DM
authors.lastname: Hoang
authors.forename: Benjamin W
authors.initials: BW
authors.lastname: Little
authors.forename: Peter D
authors.initials: PD
authors.lastname: Olmsted
authors.forename: David S
authors.initials: DS
authors.lastname: Rumschitzki
authors.forename: Youssef Zaim
authors.initials: YZ
authors.lastname: Wadghiri
authors.forename: Edward A
authors.initials: EA
authors.lastname: Fisher
mesh_terms: D000818:Animals; D003287:Contrast Media / Q000032:analysis*; D004735:Energy Transfer; D005453:Fluorescence; D005682:Gadolinium / Q000097:blood* / Q000737:chemistry; D007700:Kinetics; D008024:Ligands; D008279:Magnetic Resonance Imaging; D051379:Mice; D015394:Molecular Structure; D017646:Organosilicon Compounds / Q000097:blood* / Q000737:chemistry; D055668:Photochemical Processes; D017319:Photosensitizing Agents / Q000097:blood* / Q000737:chemistry; D013997:Time Factors
chemical_list: D003287:Contrast Media; D008024:Ligands; D017646:Organosilicon Compounds; D017319:Photosensitizing Agents; D005682:Gadolinium