Stability Studies of Starch Aerogel Formulations for Biomedical Applications.

Starch aerogels are attractive materials for biomedical applications because of their low density and high open porosity coupled with high surface areas. However, the lack of macropores in conventionally manufactured polysaccharide aerogels is a limitation to their use as scaffolds for regenerative medicine. Moreover, the stability under storage of polysaccharide aerogels is critical for biomedical purposes and scarcely studied so far. In this work, the induction of a new macropore population (1-2 μm) well integrated into the starch aerogel backbone was successfully achieved by the incorporation of zein as a porogen. The obtained dual-porous aerogels were evaluated in terms of composition as well as morphological, textural, and mechanical properties. Stability of aerogels upon storage mimicking the zone II (25 °C, 65% relative humidity) according to the International Council for Harmonization guideline of climatic conditions was checked after 1 and 3 months from morphological, physicochemical, and mechanical perspectives. Zein incorporation induced remarkable changes in the mechanical performance of the end aerogel products and showed a preventive effect on the morphological changes during the storage period.