Communication
Journal of Materials Chemistry B
angiography (MRA) is an imaging technique that uses T1 for Changjiang Scholars and Innovative Research Team in
contrast agents to shorten T1 times of blood and to obtain University (PCSIRT, Grant no. IRT1272) of China.
bright images of blood vessels by a T1-weighted imaging (T1WI)
sequence. Herein, to evaluate Dex-g-LA/MnL nanomicelles as a
T1 MRI contrast agent, a contrast enhanced MRA study of SD
rats was carried out on a clinical 3 T MR scanner. All studies
involving animals were approved by the Animal Care and Use
Committee of the Institute. Blood vessel images of the chest and
neck regions of rats were obtained aer intravenous injection of
Dex-g-LA/MnL nanomicelles or free MnL at a dosage of 0.1 Mn
3 P. Caravan, J. J. Ellison, T. J. McMurry and R. B. Lauffer,
mmol per kg body weight (Fig. 5). At one min aer adminstra-
tion of free MnL, the jugular vein, subclavian vein, and aortic
arch were clearly visible, but the imaging window was less than
ve minutes. The major reason is that low molecular weight
contrast agents are very quickly cleared through the kidneys. In
comparison, Dex-g-LA/MnL nanomicelles present a much
longer vascular imaging window. As shown in Fig. 5b, vessel
signal intensities are signicantly enhanced (hepatic portal vein
7 P. Marckmann, L. Skov, K. Rossen, A. Dupont,
was also clearly visible), and the imaging window maintained
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This journal is © The Royal Society of Chemistry 2015
J. Mater. Chem. B, 2015, 3, 1470–1473 | 1473