The Study Of Polymer Target Delivery Vector Based On Polyamino Acid

During the development of gene delivery techniques in recent decades, there are so many problem needing to be dissolved, although a lot of fruits have been made. Now it is the most important that construct the gene delivery vector which can safely and efficiently deliver gene to the specific tissue or cell. However the amount of modification on the surface of vector or complexes through the existing preparation methods was difficultly determined. In our paper, the function molecule was indirectly modified on the surface of complexes by poly-l-glutamic acid as a bridge, which can well control the amount of modification on the surface of complexes and obtained preferable transfection efficiency.Firstly, the development of gene therapy vector, the brief introduction of various vector, the main components in and characterization of polycation vector and the meaning about our paper was reviewed in our paper.Then capillary electrophoresis was used to characterize the reaction products between PLL and EGF or PEG. And the complexes formed with PLL, PEG-g-PLL and DNA at certain charge ratio was characterized by capillary electrophoresis. The PLG modified with EGF or PEG through the sole end amino of PLG, which was characterized by capillary electrophoresis, was electrostaticly adsorbed to the surface of DNA/PLL complexes, because there is too close charge to mass ratio in the reaction products between PLL and EGF or PEG to be separated by capillary electrophoresis. Then PLL, DNA, EGF-g-PLG and/or PEG-g-PLG at various charge ratio was formed into complexes, and characterization about the physicochemical properties of these complexes such as size, zeta potential, EtBr displacement and morphology was done. Also the biological property of these complexes was characterized, which include the cell transfection efficiency in medium with or without serum.In sum, we systemically studied a vector with convenient and fast modification, which was done the characterization of physicochemical properties and cell transfection experiments in which the preferable results was obtained. All these results can direct future work in assembly system.