title: Dual-frequency calcium-responsive MRI agents.
abstract: Responsive or smart magnetic resonance imaging (MRI) contrast agents are molecular sensors that alter the MRI signal upon changes in a particular parameter in their microenvironment. Consequently, they could be exploited for visualization of various biochemical events that take place at molecular and cellular levels. In this study, a set of dual-frequency calcium-responsive MRI agents are reported. These are paramagnetic, fluorine-containing complexes that produce remarkably high MRI signal changes at the (1)H and (19)F frequencies at varying Ca(2+) concentrations. The nature of the processes triggered by Ca(2+) was revealed, allowing a better understanding of these complex systems and their further improvement. The findings indicate that these double-frequency tracers hold great promise for development of novel functional MRI methods.
authors.affiliation: Department for Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, 72076 Tübingen (Germany).
authors.forename: Pascal
authors.initials: P
authors.lastname: Kadjane
authors.forename: Carlos
authors.initials: C
authors.lastname: Platas-Iglesias
authors.forename: Philipp
authors.initials: P
authors.lastname: Boehm-Sturm
authors.forename: Vincent
authors.initials: V
authors.lastname: Truffault
authors.forename: Gisela E
authors.initials: GE
authors.lastname: Hagberg
authors.forename: Mathias
authors.initials: M
authors.lastname: Hoehn
authors.forename: Nikos K
authors.initials: NK
authors.lastname: Logothetis
authors.forename: Goran
authors.initials: G
authors.lastname: Angelovski
mesh_terms: D002118:Calcium / Q000737:chemistry*; D003287:Contrast Media / Q000737:chemistry*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure
chemical_list: D003287:Contrast Media; D002118:Calcium
keywords: calcium; fluorine; imaging agents; magnetic resonance imaging