Research Of A New Type Particle Used In Particle Gun

The promising prospects of gene therapy attracted people's tremendous interest in suitble gene transfection technology. Gene therapy included: gene delivery system, expression and regulation system, curing gene. The key of gene therapy laid in gene delivery system. Among various non-viral gene delivery system, gene gun technology had obvious advantage, great potential for development and strong trend for clinical application.But there were significant obstacles to the future clinical gene gun system. Currently, the gold or wolfram particles used in gene gun was not metabolic material in life, for they tended to accumulate after entering the body, there was no way to guarantee long term security. To solve this problem, it was suggested that HAP is used to gene transfection as the micro-particles material to take the place of gold, for HAP was good biocompatibile, metabolic, and low cytotoxic, able to transfect DNA by itself.The target of this study was to prepare the specific size HAP on which DNA could be loaded efficiently and test the effect of applying such HAP in gene gun, evaluate the feasibility of the HAP replacing gold. Then working conditions was explored when HAP was used in gene gun. The study was not reported in the world.The research work was divided into three parts: Part one: preparation and modulation of HAP partclesHAP was prepared using calcium nitrate and phosphate precursor in chemical precipitation, with which the process was simple, product sizes was controllable, the Ca/P of HAP particle was closed to 1.67. The influence of temperature and boiling on product size, on ion concentration, were studied. The influence of ion on ξ potential, pH change on product components, were also studied. the morphology and structure of HAP product were observed with several methods.The results showed that the ξ potential was affected by [PO₄^3-], [Ca²⁺], [Na⁺], pH. The pH of the reacting system should be 10.5. The reaction temperature and boiling after reaction will increase the particle size. pH modulation will not change the product composition. Part two: research on adsorption of DNA to HAP...