Noninvasive MRI-SERS Imaging in Living Mice Using an Innately Bimodal Nanomaterial

作者：Yigit Mehmet V; Zhu Leyun; Ifediba Marytheresa A; Zhang Yong; Carr Kevin; Moore Anna; Medarova Zdravka^*

来源：ACS Nano, 2011, 5(2): 1056-1066.

DOI：10.1021/nn102587h

• MRI
• SEM
• gold nanoparticle
• bimodal
• Raman
• iron oxide nanoparticle
• imaging

We report a novel nanomaterial (AuMN-DTTC) that can be used as a bimodal contrast agent for in vivo magnetic resonance imaging (MRI) and Raman spectroscopy. The probe consists of MRI-active superparamagnetic iron oxide nanoparticles, stably complexed with gold nanostructures. The gold component serves as a substrate for a Raman active dye molecule to generate a surface-enhanced Raman scattering (SERS) effect. The synthesized probe produces T2 weighted contrast and can be used as a SERS active material both in silica (in aqueous solution) and in vivo. A quantitative assessment of T2 relaxation times was obtained using multiecho MRI analysis. The T2 relaxation times of AuMN-DTTC and MN (dextran-coated Iron oxide nanoparticles) were 29.23 + 1.45 and 31.58 + 1.7 ms, respectively. The SERS signature of AuMN-DTTC revealed peaks at 508, 629, 782, 844, 1080, 1108, 1135, and 1242 cm(-1). Intramuscular administration of the probe resulted in a decrease of the 12 relaxation time of muscle from 33.4 + 2.5 to 20.3 + 2.2 ms. SERS peaks were observed at 508, 629, 782, 844, 1080, 1108, 1135, and 1242 cm(-1), consistent with the in silica results. Our studies illustrate for the first time the design and in vivo application of a contrast agent, whose component modalities include MRI and SERS. The value of this agent lies in its Innately bimodal nature and its application in vivo for molecular imaging applications.

• 出版日期2011-2