Surfactant-controlled morphology and magnetic property of manganese ferrite nanocrystal contrast agent.
MnFe(2)O(4) nanocrystals (NCs) coated with three different surfactants (oleic acid, oleylamine or 1,2-hexadecanediol) and their mixtures, with sizes in range 6-12 nm, were synthesized by high-temperature decomposition of organometallic precursors. The effects of morphology and surface chemistry of MnFe(2)O(4) NCs on the magnetic properties were systematically investigated by comparing their saturation magnetization values and their capability to improve the negative contrast for magnetic resonance imaging (MRI) after converting the hydrophobic NCs to hydrophilic ones by a ligand exchange protocol. An important finding is that the magnetization values and proton relaxivity rates of MnFe(2)O(4) NCs are strongly dependent on the size and surface state of the particles that covalently bonded with different hydrophobic ligands before ligand exchange. In particular, monodisperse cubic MnFe(2)O(4) NCs could be obtained when oleylamine and 1,2-hexadecanediol were used as mixed stabilizers, and showed excellent morphology and magnetic properties. Furthermore, the low cytotoxicity and good cell uptake MR imaging of the dopamine capped MnFe(2)O(4) NCs make them promising candidates for use as bio-imaging probes.
Department of Chemistry, Shanghai Normal University, No.100 Guilin Road, Shanghai 200234, People's Republic of China.
He
H
Hu
Zhi-qing
ZQ
Tian
Jie
J
Liang
Hong
H
Yang
An-tao
AT
Dai
Lu
L
An
Hui-xia
HX
Wu
Shi-ping
SP
Yang
D000588:Amines / Q000737:chemistry; D002470:Cell Survival; D003287:Contrast Media / Q000737:chemistry*; D055590:Electromagnetic Phenomena; D005233:Fatty Alcohols / Q000737:chemistry; D005290:Ferric Compounds / Q000737:chemistry*; D006367:HeLa Cells; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D017895:Manganese Compounds / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D019301:Oleic Acid / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D013501:Surface-Active Agents / Q000737:chemistry*; D013696:Temperature; D014961:X-Ray Diffraction
D000588:Amines; D003287:Contrast Media; D005233:Fatty Alcohols; D005290:Ferric Compounds; D017895:Manganese Compounds; D013501:Surface-Active Agents; C551151:manganese ferrite; C470411:1,2-hexadecanediol; D019301:Oleic Acid; C008703:oleylamine