The investigation of Positively chargd catanionic vesicle-DNA association behavior

• Main Authors: Chi-Da Lu, 呂奇達
• Other Authors: Chien-Hsiang Chang
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/57524240031352725154

碩士 === 國立成功大學 === 化學工程學系碩博士班 === 93 === 　This study investigated the behavior of catanionic vesicle-DNA association by particle size and zeta potential analyses. Two approaches were applied to prepare catanionic vesicles. The first is to mix the anionic surfactant, sodium tetradecylsulfate, and the cationic surfactant, tetradecyltrimethylammonium bromide, in water with an appropriate ratio, in order to spontaneously form positively charged catanionic vesicles. The second is to obtain the ion pair amphiphile (IPA) first by mixing the anionic surfactant, sodium dodecylsulfate, and the cationic surfactant, hexadecyltrimethylammonium bromide, in water. The IPA was then forced to form catanionic vesicles with positive charges by an appropriate process. The catanionic vesicle dispersions were mixed with various concentrations of type XIV DNA solutions, and the particle size and zeta potential of the mixed systems were analyzed. Based on the zeta potential data obtained before and after mixing, one could conclude that the positively charged catanionic vesicles were able to associate with DNA. However, the particle size measurements indicated that stability of the catanionic vesicles after associating with DNA was unsatisfactory. As a result, a proper amount of cholesterol was added in the formulation of forming catanionic vesicles by the forced approach, in order to prepare vesicle dispersions with enhanced stability. It was found that dispersions of the vesicles in the presence of cholesterol had excellent stability, which was not affected even the dispersions were significantly diluted. Moreover, after interacting with plasmid DNA, the vesicle dispersions still maintained reasonable stability.