| Objectives:This study was designed to develop a novel magnetic resonance (MR) probe for the antigen VEGFR-2 and investigate its imaging features in vitro。Materials and Methods:Molecular probes were achieved through ultrasmall super-paramagnetic iron oxide nanoparticles (USPIOs) conjugated to antibodies VEGF using a chemical method. In the control group, USPIOs were used as control.DLS was used to e-valuate the conjugation reaction. The cytotoxicity of the probe was measured using the memethyl-thiazolyl tetrazolium assay,and its cell-labeling efficiency was evaluated by Prussian blue staining. In vitro cell MR imaging was performed to evaluate the targeting of the probe to the cells.Results:DLS displayed an optimal conjugation of USPIOs to VEGF and mIgG. Va-rious blue-staining particles were found in cells labeled with the molecular probe at diffe-rent iron concentrations, and density of particles was positively related to the iron concer-ntration. The MTT assay showed that there was no difference in cellular toxicity between VEGFR USPIO-labeled and nonlabeled cells (P>0.05). In vitro cell MR imaging show-ed that there was an obvious decrease in signal intensity for the probe-labeled cells com-pared to nonlabeled cells.Conclusion:VEGF-USPIO conjugates have the good biological characteristics as VEGFR-targeted MR imaging agents。... |
