Starch aerogel loaded with poorly water-soluble vitamins through supercritical CO2 adsorption

Maize starch aerogel (MSA), a biocompatible and biodegradable support, was loaded with a-tocopherol (vitamin E) and menadione (vitamin K-3), two poorly water-soluble vitamins using supercritical carbon dioxide adsorption. Adsorption experiments were carried out at 15 MPa and 40 and 60 degrees C. Adsorption equilibrium data were measured and represented as isotherms. Kinetic data, related to adsorption rates, showed that the adsorption process, for both vitamins, was best described by a pseudo second-order model. Vitamin/MSA composites were characterized using FT-IR spectroscopy, X-ray diffractometry and specific surface area determination. In order to study the properties of the adsorbed MSA, as a vitamin delivery system, in vitro dissolution tests were performed. These analyses showed that vitamin loading was about 95-98% with respect to the expected concentration, for both the cases. The dissolution rate in phosphate buffered saline solution (PBS) was largely improved: it was 3.5 times faster than the one of unprocessed vitamin in the case of menadione and about 16 times faster in the case of a-tocopherol. (C) 2017 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.