Objective: To synthesize the RGD-modified magnetic resonance imaging (MRI)-visible gene transfer nanocarrier and assess its gene delivery ability and MRI visibility for hepatocellular carcinoma.
Methods: The multifunctional nanocarrier RGD-PEG-PEI-SPION was constructed. And the degree of binding between nanocarrier and siRNA was determined by agarose gel electrophoresis. The zeta potential and particle size of cationic polymer vectors were measured with a Zeta-Plus instrument. Immunocytochemical assay was performed for detecting the expression of α(v)β(3) in Bel-7402 cells. The active targeting ability of nanocarrier to Bel-7402 cells was evaluated by flow cytometry and laser confocal microcopy. The MRI visibility of nanocarrier to Bel-7402 cells was assessed.
Results: RGD-PEG-PEI-SPION could condense siRNA entirely at a N/P ratio of 2.8; the membranes of Bel-7402 cells possessed an enrichment of α(v)β(3) receptors. At a nitrogen/phosphate ratio of 10, the particle size of RGD-PEG-PEI-SPION/siRNA attained a constant size of 85.2 ± 5.6 nm, the zeta potential reached +12.4 ± 1.2 mV, the gene transfection efficiency of nanocarrier to Bel-7402 cells attained 71.2% ± 2.1% and the cells showed significantly stronger RGD-PEG-PEI-SPION (red) and siRNA (green) fluorescence under laser confocal microcopy. The cells incubated with RGD-PEG-PEI-SPION exhibited significantly lower normalized MR T(2)(*)WI signal intensity.
Conclusion: A RGD-modified MRI-visible gene delivery nanocarrier RGD-PEG-PEI-SPION has been successfully synthesized.It has a higher transfection efficiency of transferring siRNA into Bel-7402 cells and could sensitively detect hepatocellular carcinoma with MRI.