Abstract
a-tocopherol (TOC), a poorly water-soluble vitamin, was impregnated using supercritical carbon dioxide in two different porous supports: an inorganic one (silica aerogel, SA) and a biopolymer one (maize starch aerogel, MSA). The composite systems can be used for the attainment of novel delivery systems with a rapid or controlled vitamin dissolution rate. TOC impregnation experiments on both the supports were carried out at a pressure of 15 MPa and a temperature of 60 °C. Impregnation equilibrium data were measured and represented as isotherms, whereas impregnation kinetic data were obtained by determining the TOC uptake on the two supports at various times. The TOC/aerogel composites were characterized by FESEM analysis and specific surface area determination. To study the properties of the adsorbed aerogels, as vitamin delivery systems, in vitro dissolution tests were performed. The dissolution rates of TOC charged in silica aerogel or maize starch aerogel using phosphate buffered saline solution (PBS) were compared with the one of the unprocessed vitamin.
