ONE-STEP PREPARATION AND LOADING OF BACTERIAL CELLULOSE AEROGELS WITH BIOACTIVE COMPOUNDS FOR SLOW-RELEASE APPLICATIONS

摘要

The current paper communicates a straightforward approach to highly porous,ultra-lightweight bacterial cellulose aerogels with densities of down to 8 mg/cm3 using supercritical carbon dioxide as drying medium.Bacterial cellulose alcogels were confirmed to feature good dimensional stability throughout scCO2drying.The obtained aerogels are quantitatively rewettable without significant shrinking which renders them interesting matrices for controlled release applications.Antisolvent precipitation of bioactive compounds inside the alcogel pore network and subsequent conversion of the loaded lyogels into aerogels using scCO2 was shown to be an effective method as the two steps can be performed at once under only slightly different pressure conditions.The release profiles of the two model compounds Lascorbic acid and D-panthenol were predicted using the Korsmeyer model and compared with experimental values.The good agreement between predicted and measured values confirmed that the release of similar bioactive compounds can be largely controlled by the thickness of the bacterial cellulose layer.