The delivery of triamcinolone acetonide using emulsion-type systems

This dissertation aims to formulate a product that would be useful in the lung delivery for hydrophobic drugs. In particular, it is anticipated that these formulations would be used as prototypes for pulmonary delivery of corticosteroid drugs, such as triamcinolone acetonide. The prototype system consisted of an oil-in-water emulsion with droplets in the 100 nm radius range. Peppermint oil was used as the internal phase, and the ionic surfactant, sodium oleate, was chosen to facilitate detailed characterizations of the emulsion properties. Small amounts of ethanol and vitamin E were added to improve the formulation physical characteristics.; It was decided to make emulsions of different particle size and follow their stability by monitoring the surface density of the surfactant rho s, which was named to be a ratio of amount of surfactant bounded to the surface of the droplets in the dispersed phase and area of the droplets in the oil phase. A homogenizer was utilized to make emulsions of different sizes having different densities of the surfactant. Two methods were used to identify the nature of the emulsions. The method, which was developed to calculate the density of the bounded surfactant per unit area of the droplets in the oil phase, was developed using fundamental science, where the total surface area (TSA) of the dispersed phase was found by using Gaussian statistical analysis and the bound amount of surfactant was estimated from the mass balance. Particle size distributions were obtained by running a sample of the investigated emulsion through a particle-analyzing machine. Once ready, a computer would give results in the form of Gaussian analysis with median diameter and standard deviation, which was subsequently used to obtain the total surface area of the droplets in the emulsion. The mass balance of the surfactant was found using the equation MT = MS + MO + MW, where MT is the total surfactant amount placed into the formulation, MS, MO and M W are the amounts of surfactant found on the droplet surfaces, dissolved in oil phase and dissolved (ionized) in the continuous aqueous phase, respectively. Conductivity measurements were used to identify and quantify the free surfactant amounts in the water phase. Characterizations of the emulsions included plots of rhos vs. TSA and the conductivity vs. different surfactant concentrations. The latter plot was also used only at the concentration values above the critical micelle concentration (CMC), which was determined to be 2.6mg/mL. The homogenization was done at different speeds and for different durations. (Abstract shortened by UMI.)...