Dendrimer-Based MRI Contrast Agents
Journal of Medicinal Chemistry, 2007, Vol. 50, No. 14 3193
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Igor Pro (Wavemetrics, Inc., Lake Oswego, OR). The clearance
rates were determined by fitting the decay curves to a single-
exponential decay function with the baseline fixed to zero, and
clearance pseudo-first-order rate constants were calculated (Table
1). Results were averaged for all animals in each group (n ) 4-5).
Statistical Analyses. The statistical analysis of the differences
between clearance rates and relaxivity values among the three agents
was assessed with a student’s t-test using an Excel spreadsheet
(Microsoft, Redmond, WA).
Acknowledgment. This research was supported in part by
the Intramural Research Program of the NIH, National Cancer
Institute, Center for Cancer Research. This project has been
funded in part with federal funds from the National Cancer
Institute, National Institutes of Health, under Contract N01-CO-
12400. We also note the helpful discussions with Pierre Arronax
and Diane Milenic during the course of these studies.
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Supporting Information Available: Characterization of side
products, synthesis of the G4-1B4M60-Gd42, MALDI-TOF/MS,
NMR, SE-HPLC chromatograms, and relaxivity curve results for
the compounds are presented. This material is available free of
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