Preparation of drug loaded polymer composite particles by supercritical impregnation method

In recent years, the drug treatment systems are getting inadequate in increasing demands and new developments that improve drug performance are needed. The studies in this field are focused on developing drug carrier particle systems. The most common and typical examples of this field are drug loaded polymer particles. Drug?polymer composite particles, primarily used in controlled drug release systems, are consequence of solving some conventional problems and overcoming inadequacies in this field.In this master thesis, drug-polymer composite particles are prepared in presence of supercritical carbondioxide (scCO2) by using ibuprofen (IB), a drug staple, and polyvinyl pyrrolidone (PVP), hydroxypropyl methylcellulose (HPMC) and beta cyclodextrin (ßcD) polymers. Supercritical Solvent Impregnation (SSI) method, an effective, easily performed and environmentally method, is used to prepare particles. In this method, supercritical values are exceeded by adjusting temperature and pressure. After reaching supercritical conditions, CO2 dissolves ibuprofen, penetrates into the polymer, increases the cavities in the polymer matrix, and the polymer swells. By controlled decreasing of temperature and pressure, the swelling polymer contracts into initial volume and the dissolved ibuprofen is detained in the polymer. Drug+polymer composite particles are prepared according to this procedure.Pressure, temperature, impregnation time and drug/polymer ratio are the parameters affecting the loading of drug into the polymer. In the experiments, different conditions of temperature, between 40-50 oC, pressure, 100-200 bar, drug polymer ratio, 1/1, 1/2, 1/3, 1/4 and impregnation time, 1-6 hours, were tested to determine the effects of these parametres on the particle size-dispersion, morphology, drug loading species by using different analytical techniques, and then optimum process conditions were investigated to obtain good grain particles. As a result of experiments and analysis, under the conditions of degradation temperature of drug, each of the increasing temperature, pressure, impregnation time and drug/polymer ratio, increases the drug loading. It is concluded that, the drug/polymer ratio is the most effective parameter that influences the drug loading.