Preparation And Evaluation Of MRI Contrast Agent LA-PEG-SPION For Hepatoma-targeting

Objective:The asialoglycoprotein receptor(ASGP-R)is a receptor protein which expressed on the surface of liver cells specifically.It can identify special ligands with galactose residues efficiently,and absorb them by endocytosis.There are numerous ASGP-R existing in the surface of hepatoma cells.It can be used as a hepatoma-specific target to develop drugs.Therefore,we aim to synthesis a MRI contrast agent(LA-PEG-SPION)which is specifically targeted to hepatoma cell's surface receptor asialoglycoprotein(ASGP-R),and to evaluate the targeting effect in hepatoma and the effect of MR imaging.Method:Hydrophilic superparamagnetic iron oxide nanoparticles(SPION)was synthesized via coprecipitation method.And to synthesize LA-PEG-SPION by using condensation method to connect LA-PEG-COOH with SPION.Dynamic light scattering(DLS),X-ray diffractometry(XRD),Fourier transform infrared(FT-IR)spectra,and Transmission electron microscopy(TEM)were used to measure products.Cell viability was determined by MTT assay with human hepatoma cell line HepG2 and human cervical carcinoma cell Hela.Prussian blue staining and Flow cytometry were used to assay its ability of hepatoma cell uptake.In vitro MRI was used to confirm its effect of targeted imaging.Result:The TEM pictures of LA-PEG-SPION showed that they were spherical with regular morphology.The result of dynamic light scattering proved that LA-PEG-SPION have the mean size of(30±4.5)nm and the surface potential of(31±1.5)mV.Cell viability demonstrated that LA-PEG-SPION showed nontoxicity even if the concentration of it reached to 400?g/mL.Prussian blue staining pictures showed that the intracellular uptake of LA-PEG-SPION was greater than SPION.There are more blue-stained particles in test group than control group.The result of Flow cytometry showed that the rate of fluorescent labeling reached to 68.8%.In vitro MRI showed that the signal intensity of HepG2 cells on T2WI was much lower than control group.Conclusion:LA-PEG-SPION nanoparticles was synthesized successfully.It has potential to provide experiment basis for further research in vivo and in clinical.