Preparation Of Microemulsion And Vesicle And The Study Of Their Entrapment Efficiency Of All-trans Retinoic Acid

Tween80/ n-Butylalcohol/H2O microemulsion and spontaneous vesicle systems which were used as all-trans retinoic acid (ATRA) drug delivery systems were prepared. The influence of temperature and concentration of NaCl on the region were determined with ternary diagrams. The O/W, W/O and B.C. regions were divided by dying and conductance methods. The micropolarity in microemulsion and diameter were measured by Fluorescence and Dynamic Light Scattering. Based on the study of our group, spontaneous vesicle systems in both aqueous and ethanol-water solution of mixture of cationic surfactants dicetyl dimethyl ammonium chloride (DCDAC) and tri-(dodecyl-dimethyl-dydroxypropyl ammonium chloride) phosphate (PTA) with sodium bis-(2-ethylhexyl) sulfosuccinate (AOT), sodium dodecyl sulfate (SDS) and sodium dodecyl benzene sulfonate (SDBS) were studied respectively. The vesicle sample was measures by TEM and AFM, while their diameters and polydispersity were measured with DLS. The entrapment efficiency of ATRA in microemulsion and spontaneous vesicle systems were measured with dialysis bag-Ultraviolet Spectrophotometer and first order derivative UV Spectrophotometer method respectively. The anti-cancer activity of ATRA in microemulsion was investigated with cancer cells H446.Results shown that the influences of temperature and salinity on microemulsion region were very slight. O/W microemulsion forms when water content over 64%. The micropolarity in microemulsion decreased with the increasing of concentration of n-Butylalcohol and ATRA. The diameter of microemulsion was around 56nm, and unchanged within a month. Spontaneous vesicles were formed in certain molar proportion and total surfactant concentration. Multi-vesicle and tubule structure in DCDAC/SDS system were observed in TEM photos. The diameter of spontaneous vesicle which formed with DCDAC reached micron degree and larger than vesicles formed with PTA. The highest entrapment efficiencies for ATRA of DCDAC/AOT=1/9,DCDAC/SDS=5/5,DCDAC/SDS=1/9 spontaneous vesicle in 50% ethanol-water solution were 62%, 67% and 37% with the total concentration 3.0×10-3mol/L,1.0×10-3mol/L and 1.0×10-3mol/L respectively. The microemulsion enveloping ATRA possessed eminent sustaining release efficiency and the efficiency was further confirmed with the growth inhibitory effect test on cancer cells H446.Some job was created in this work:1. Spontaneous vesicle system of DCDAC/AOT, DCDAC/SDS and DCDAC/SDBS were prepared for the first time, which could be formed steadily in ethanol-water solution. Spontaneous vesicle systems in non-aqueous solution were used as ATRA drug delivery.2. The tubule structure and its growth were observed in aqueous of DCDAC/SDS3. Tween80/ n-Butylalcohol/H2O microemulsion were prepared, in which n-Butylalcohol was used as oil and cosurfactant at the same time. The solubility and stability of ATRA were increased.