Preparation Of Cationic Lipid Microbubbles Carrying HVEGF₁₆₅ For The Treatment Of Pulmonary Hypertension

Objective:Micron lipid microbubbles and cationic lipid microbubbles were prepared and their physicochemical properties were detected.Two kinds of lipid microbubbles carrying hVEGF165 were prepared to detect the gene plasmid carrying rate and evaluate the ability of the two vectors to carry the gene plasmid.Method:Two kinds of lipid microbubbles were prepared by thin film hydration and mechanical shock method.Cationic lipid microbubbles were prepared by adding dc-chol as the cation on the surface of the lipid film forming materials and making the carrier surface carry a positive charge.After centrifugation,the morphology,size,distribution and concentration of the two microbubbles were observed under a light microscope.The average particle size and surface potential of the two kinds of microbubbles were detected.The two kinds of microbubbles were connected with hVEGF165 gene plasmid by incubation electrostatic adsorption method,and the gene plasmid connection rate was detected.Results:The opaque milky liquid was observed by naked eyes with self-made contrast agent.Observation by optical microscope showed a large number of microbubbles,which were spherical,uniform in size,regular in shape and good in dispersion.The perfluoropropane gas in the outer film and inner layer can be observed by scanning electron microscope.Two kinds of microbubbles were prepared within one hour,and the results were analyzed by using malvern micron particle size.The results showed that the average particle size and surface potential range were highly concentrated.Ordinary lipid microbubbles:the average particle size:1.40±0.28um,the surface charge:-2.41±0.51m V,and the average concentration:3.3.32±0.34x108 ?/ml.Cationic lipid microbubbles:average particle size:1.31±0.23um,surface charge:28.00±1.84mV,average concentration:3.17±0.16x108?/ml.Electrostatic adsorption method by incubation of VEGF gene plasmid of two kinds of lipid microbubble,gene plasmid connection rate calculation,comparing two cell's ability to carry genes plasmid,cationic lipid microbubble carry hVEGF165 gene carrying rate is significantly higher than ordinary lipid microbubble,cationic lipid microbubble gene's ability to carry higher than ordinary lipid microbubble.Conclusion:Self-made lipid microbubbles can flexibly prepare lipid microbubbles with different particle sizes,surface charges and concentrations by changing the preparation conditions of microbubbles as required.Cationic lipid microbubbles have a high carrying rate of hVEGFi65 and a strong ability to carry gene plasmids,which can be used as a good carrier for in vivo transfection of genes.