No abstract

This work presents new experimental phase equilibrium data for mitotane in supercritical CO 2 and mitone in supercritical CO 2 plus ethanol. The synthetic-static method in a high-pressure variable-volume view cell was used to measure the solidÀfluid (SF) and the fluidÀfluid (FF) equilibrium data. The phase equilibrium experiments were carried out in the temperature range from (298 to 333) K and in the pressure range from (3.44 to 21.84) MPa. The PengÀRobinson equation of state (PR-EoS) was used for describing the fluid phases, and an expression for the fugacity of pure solid mitotane was used for representing the solid phase. This made it possible to model the SF and FF equilibrium data for the CO 2 + mitotane mixtures. Fair agreement was found between experimental and calculated values.

New data on phase equilibria

In this work, was investigate the effect of the molecular weight of poly(3hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) on the preparation of medroxyprogesterone acetate (MPA)-encapsulated polymeric nanoparticles (PNPs) using the supercritical fluid extraction of emulsions (SFEE) technique.Particles with diameters between 850 nm-183 nm were obtained using PHBV of molar mass reduced and variable between 210 KDa to 14 KDa, thus establishing a direct relation between the size of the PNPs prepared with SFEE and the molar mass of the polymer. These results were contrasted with those obtained with the conventional emulsion solvent evaporation (ESE) technique. PNPs prepared by SFEE were observed to be smaller than those produced by ESE, for all polymer molecular weights (MW) studied. The encapsulation efficiency (EE%) of MPA in the PNPs preparedwith the SFEE technique, and with the lowest MWPHBVwas determined to be 70%. The in vitro release kinetics for this systemindicated that themean time for 35% release of MPA was 18h. Both a first and a second-order kinetics models provide a good fit to the release profile of MPA from the PHBV PNPs.Cellular viability results indicate low toxicity profiles of the PHBV PNPs prepared with the SFEE technique, even at high PNP concentrations.