The Preparation And Property Research Of DNA Nano Carriers Based On Polyethylene Imine And Hyaluronic Acid

The progress of gene therapy was imported normal gene and corrected defects or abnormal genes,ideal carriers should be designed with safety and high efficiency,but it was hard to balance safety and efficiency with existing carriers.Branched polyethylenimine with the molecular weight of 25 kDa has been the most potential and widely used cationic polymer because of its "proton sponge effect",high transfection efficiency and large condensing capacity,but the disadvantages of polyethyleneimine is high toxicity and no specific targeting.DNA nano carriers was expected to achieve high efficiency,and low toxicity with polyethyleneimine and hyaluronic acid which was the targeted CD44 receptor cell material for targeted gene therapy.PEI/pDNA/HA and PEI/DNA/HA ternary complexes nano carriers were prepared with polyethyleneimine(PEI)and hyaluronic acid(HA)respectively with pDNA which could express green fluorescent protein and molecular weight of 152 Kb double-stranded viral DNA via electrostatic self-assembly,which was characterized by DLS,Transmission electron microscopy(TEM)of hydrodynamic size,potential and morphology,gel electrophoresis experiment evaluated DNA condensing capabilities of nano carriers,whether the expression of green fluorescent protein was observed through the vero cells transfection.The optimized conditions to prepare the ternary complexes nanocarriers was negatively charged components added to the positive charge composition,pH 7.4,the concentration of PEI was 0.5 mg/mL,the concentration of HA was 0.2 mg/mL.Size distribution of nano carrier between 100~200 nm,TEM observations was about 57 nm in diameter,uniform spherical structure,electrophoresis figure compared with naked DNA,which observed condensing DNA ability with the nano carrier,the expression of green fluorescent protein could be revealed by fluorescence microscope after vero cells transfection,which proved that DNA transported into the nucleus to transcript and translate to express the new proteins.PEI/DNA/HA ternary complex nano carrier which size was distributed between 150~300 nm,100 nm diameter and the homogeneous spherical structure was observed through TEM,which had the ability to condense DNA.The hyaluronic acid(HA)modified polyethylene glycol(mPEG)was characterized by Infrared spectroscopy,PEI/pDNA/HA-mPEG ternary complexes nano carriers was prepared through electrostatic interactions,its physical and chemical properties were characterized through DLS,electron microscopy and electrophoresis.PEI/pDNA/HA-mPEG ternary complexes nano carrier,particle size distribution between 200~300 nm,the TEM figure showed its structure is loose,but it still had certain ability to condense DNA.Chemically modified poly(trimethylene carbonate),the HA-PEG-PTMC polymer was characterized by Infrared spectroscopy,different factors were studied with the preparation of PEI/pDNA/HA-PEG-PTMC ternary complexes nano carrier,DLS and TEM characterized for size,potential,morphology and particle diameter,gel electrophoresis experiment revealed new carrier condensing capability of DNA,BSA adsorption experiments was to explore the hydrophobic part in the resistance of protein adsorption.The particle size distribution of PEI/ pDNA/HA-PEG-PTMC ternary complexes nano carrier was about 300~400 nm,potential in 19.7~29.6 mV,TEM figure of particles was about 50 nm in diameter,electrophoresis showed DNA nano carrier with a certain condensing ability,the trend of the UV figure showed that the carrier play a role in certain BSA adsorption resistance.