title: [Biocompatibility of polyethylene imine (PEI)-coated magnetic Fe₃O₄ nanoparticles in SHI-1 cells].
abstract: OBJECTIVE
  To explore the feasibility of magnetic resonance cell imaging technology by using polyethylene imine (PEI)-coated magnetic nanoparticles of Fe₄O₄ (PEI-Fe₄O₄-MNPs) to track cell biology behavior.
  
  
  METHODS
  Endocytic PEI-Fe₄O₄-MNPs in SHI-1 cells were observed by transmission electron microscopy (TEM) . Iron contents of nano-labeled cells were analyzed by inductively coupled plasma-atomic emission spectroscopy (ICP-AES) and Prussian blue staining. The proliferation ability of labeled cells was detected by cell counting kit-8 (CCK-8) assay; the differentiation and colony-forming abilities were also observed. SHI-1 cells without endocytosing PEI-Fe₄O₄-MNPs were used as control.
  
  
  RESULTS
  Our data showed that PEI-Fe₄O₄-MNPs could label SHI-1 cells. The labeling efficiency depended on the nanoparticles' concentration and the duration of cells treating. Inhibition rates of SHI-1cells labeled by 60-100 μg Fe/ml PEI-Fe₄O₄-MNPs were much higher than of 5-50 μg Fe/ml ones following treating by 5-100 μg Fe/ml PEI-Fe₄O₄-MNPs for 48 hrs. The expressions of CD11b and CD14 were (78.4±18.5)% and (18.7±2.9)% in control vs (83.3±14.2)% and (20.4±2.1)% in cells fractions treated by 30 μg Fe/ml PEI-Fe₄O₄-MNPs. Clony-forming rates of SHI-1 cells labeled by 0, 20 , 50 μg Fe/ml PEI-Fe₄O₄-MNPs were (25.20±7.22)%, (25.93±13.15)%, (23.37±9.33)%, respectively. Differentiation and colony-forming potentials of labeled cells were similar with control in the certain range of PEI-Fe₄O₄-MNPs concentration.
  
  
  CONCLUSIONS
  SHI-1 cells were efficiently labeled by PEI-Fe₄O₄-MNPs with well biocompatibilities in proper range of concentration, the latter could be coupled with magnetic resonance imaging (MRI) to track cells in vivo.
authors.affiliation: Jiangsu Institute of Hematology, First Hospital of Soochow University, Suzhou, China.
authors.forename: Xiao-li
authors.initials: XL
authors.lastname: Chao
authors.forename: Zi-xing
authors.initials: ZX
authors.lastname: Chen
authors.forename: Su-ning
authors.initials: SN
authors.lastname: Chen
authors.forename: Jian-nong
authors.initials: JN
authors.lastname: Cen
authors.forename: Xiao-fei
authors.initials: XF
authors.lastname: Qi
authors.forename: Hong-jie
authors.initials: HJ
authors.lastname: Shen
authors.forename: Li
authors.initials: L
authors.lastname: Yao
authors.forename: Yuan-yuan
authors.initials: YY
authors.lastname: Wang
mesh_terms: D045744:Cell Line, Tumor; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D005290:Ferric Compounds / Q000737:chemistry*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008280:Magnetics; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000737:chemistry*; D011094:Polyethyleneimine / Q000737:chemistry*
chemical_list: D020099:Coated Materials, Biocompatible; D005290:Ferric Compounds; D011094:Polyethyleneimine