Abstract: Objective To investigate the best method of polyethylenimine(PEI) coated superparamagnetic iron oxide(SPIO) labeled human amniotic mesenchymal stem cells(hAMSCs) and to observe its influence on cell proliferation.Methods hAMCs were incubated in DMEM/F12 containing PEI -SPIO of 6,8,10,12mg/L,using prussian blue staining method and atomic absorption spectrophotometry method analysis label efficiency. To investigate the PEI -SPIO labeled hAMSCs proliferation activity using MTT analysis.Results hAMSCs with PEI -SPIO labeled detectable amounts of iron particles.PEI -SPIO is concentration dependent; 10,12mg/L concentration significantly inhibit cell proliferation(P <0. 05).Conclusions The PEI -SPIO concentrations of 8mg/L labeled hAMSCs can obtain good labeling effect, and does not influence cell proliferation activity.

Key words: Human amniotic mesenchymal stem cells, Polyethylenimine, Superparamagnetic iron oxide, Label, Cell proliferation