Biological and magnetic contrast evaluation of shape-selective Mn-Fe nanowires.
One-dimensional composite Mn-Fe oxide nanostructures of different sizes (nanoneedles, nanorods, and nanowires) were prepared by a linker-induced organization of manganese-doped iron oxide nanoparticles. The nanostructures were obtained by the treatment of MnFe(2)O(4) nanoparticles in the presence of cystamine. The average lengths of nanoneedle, nanorod, and nanowire are approximately 400, 800, and 1000 nm, respectively. High-resolution transmission electron microscopy (HR-TEM), energy-dispersive X-ray (EDX) spectroscopy, and inductively coupled plasma-optical emission spectroscopy (ICP-OES) were employed to characterize the morphologies and the elemental contents of the nanostructures. As an example of their potential applications, these nanostructures were explored as the cell-labeling agents for magnetic resonance imaging (MRI). The magnetic contrast properties of the nanostructures were characterized by a 1.5 T (Tesla) whole body MR system. 10 microg/mL of the nanostructures caused substantial negative contrast. After in vitro incubation, the nanostructures could be effectively incorporated into the cells of a monocyte/macrophage cell line (RAW264.7). These cells' viability and proliferation potential were not affected when the labeling concentration was less than 50 microg/mL.
Center of Novel Functional Molecules, Department of Chemistry, The Chinese University of Hong Kong, Shatin, NT, Hong Kong. cfleung@cuhk.edu.hk
Ken Cham-Fai
KC
Leung
Yi-Xiang J
YX
Wang
Haohao
H
Wang
Shouhu
S
Xuan
Chun-Pong
CP
Chak
Christopher H K
CH
Cheng
D000818:Animals; D002460:Cell Line; D003287:Contrast Media; D007089:Image Enhancement / Q000379:methods*; D007501:Iron; D008264:Macrophages / Q000166:cytology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008345:Manganese; D049329:Nanostructures / Q000648:ultrastructure; D051381:Rats; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D003287:Contrast Media; D008345:Manganese; D007501:Iron