preparation and preliminary evaluation of dual-functional nanoparticles for mri and sirna delivery

in order to improve the transfection efficiency of gene vectors and monitor the effect of gene therapy, this study prepared a drug delivery vector with dual functions. the thiourea reaction was used to synthesize polyethyleneimine (pei, mw: 1.8 kda) with superparamagnetic iron oxide nanoparticles (spion) (pei1800-spion), and the lipid polycationic gene vector pei1800-spion loaded cationic liposome (lp-pei1800-spion) was further prepared by ethanol injection method. agarose gel electrophoresis experiment, cytotoxicity experiment, and in-vitro gene silencing experiment were used to evaluate the vector and screen the optimal prescription of lp-pei1800-spion/sirna. when the weight ratio of lp-pei1800-spion to sirna is 20, the transfection efficiency of the nanoparticles was the highest, and the silencing efficiency of the target protein was the largest. the cytotoxicity of lp-pei1800-spion was low; when the concentration was in the range of 1-50 μg/ml, the survival rate of the four types of cells was above 80%. prussian blue staining experiments and in-vitro mri imaging experiments showed that cells had significant uptake and imaging capabilities for lp-pei1800-spion. in conclusion, the visualized polycationic lipid sirna delivery vehicle (lp-pei1800-spion) was successfully prepared in this experiment, which provides a research basis for further theranostics of liver cancer.