Characteristics Associated Magnetic Behavior Of Surfactant And Drug

The unique features of magnetic vesicles make them have high theory significance and practical application potential. Magnetic nanoparticles and magnetofluid in traditional magnetic vesicles have the disadvantages of nonbiocompatibility and low stability, which limits the application of magnetic vesicles in the field of medicine. As the disadvantages of magnetic vesicles, we synthetize paramagnetic surfactants, then use them to form magnetic vesicles without adding magnetic nanoparticles and magnetofluid. In addition, we discuss encapsulation percentage and drug release of magnetic vesicles carrying doxorubicin hydrochloride, for the purpose of seeking out a system that has high drug-loading capacity, controlled release and strong magnetic field response, to provide a theoretical basis for the application of magnetic vesicles in the field of medicine. The details are as follows:1. The synthesis and aggregation behavior of paramagnetic Gemini metallosurfactantsParamagnetic Gemini metallosurfactants Cn-Cu-Cn (n=8,12,16) are synthesized, and first characterized by1H NMR, FT-IR, LC-MS, elemental analysis and EPR. Their aggregation behavior are investigated from air-liquid interface to solution by surface tension、electrical conductivity, and the results show that with increasing hydrophobic chain, the cmc decreases but the γcmc almost unchanged. The micellization of C8-Cu-C8、C12-Cu-C12is entropy driven, but for C16-Cu-C16, it is enthalpy driven at low temperature but entropy driven at high temperature. Compared with corresponding ligand, Cn-Cu-Cn has higher efficiency and lower capacity of lowing the surface tension.2. Magnetic vesicle formation and stability of Cn-Cu-Cn/H2OUsing paramagnetic surfactants Cn-Cu-Cn (n=8,12,16) to form magnetic vesicles and through electrical conductivity, DLS and negative staining-TEM to prove the formation of vesicles and observe the morphology of vesicles. Besides, techniques like negative staining-TEM, FT-IR are used to study the influences of time, temperature, inorganic salt and magnetic field on the stability of vesicles. The results show that we can obtained the monodisperse Cn-Cu-Cn vesicles by ultrasonic method; cvc decreases with the hydrophobic chain length increaseing; vesicles have good stability on high temperature, time, inorganic salts and magnetic field. 3. The properties of magnetic vesicles carrying doxorubicin hydrochlorideThe encapsulation percentage and drug release at different sustained-release conditions of C12-Cu-C12magnetic vesicles carrying doxorubicin hydrochloride are observerd by UV-vis, FT-IR, negative staining-TEM and so on. Drugs can exist in different fields of vesicles:the interior of vesicle, the surface of the vesicles, and the aqueous continuous phase in the form of complexes with C12-Cu-C12molecular.10mM C12-Cu-C12system has high encapsulation efficiency, and the efficiency decreases with the concentration of C12-Cu-C12decreasing or the amount of doxorubicin hydrochloride increaing. Delivery system has obvious sustained release effect, and with the decreasing pH of dialysis environment, efficiency of drug release increases, which has a good targeting release effect for cancer area.4. The synthesis and aggregation behavior of surfactant with magnetic conterionSurfactant with magnetic conterion [C10mim][FeCl4] are synthesized, and first characterized by UV-Vis, FT-IR, and VSM. The results of surface tension and electrical conductivity show that the micellization of [C10mim][FeC44] is entropy driven and with increasing of temperature, the cmc of [C10mim][FeCl4] increases. Compared with [C10mim]Cl,[C10mim][FeCl4] is more likely to form micelle. Besides, techniques like turbidity, TEM, DLS are used to study the interaction of [C10mim][FeCl4] and SDBS, and the results show that [C10mim][FeCl4] and SDBS can Self-assembly to form vesicles.