ALGINATE AEROGELS DRIED BY SUPERCRITICAL CO2 AS HERBAL DELIVERY CARRIER

Abstract

Herbal medicinal plant have been recognized as alternative and natural drugs for therapeutic purposes due to their high content of phytocompounds with anti-bacterial, antioxidant and anti-inflammatory properties. Low solubility and poor absorption of medicinal compounds are seen as major challenges for herbal drugs. Impregnation of these substances into aerogels as a carrier is an innovative to improve poorly soluble compounds. In this work, alginate hydrogels were produced via sol-gel processing method and dried by supercritical CO2 drying to obtain high porous structure of alginate aerogels. Alginate is a type of polysaccharides that is widely applied in biomedical, pharmaceuticals, cosmetics, and foods due to its nontoxic, stability and versatility properties. Plant extracts of Clinacanthus nutans Lindau (C. nutans) were impregnated into the alginate aerogels via liquid media followed by supercritical drying and via supercritical CO2 assisted impregnation technique. Results exhibited that the initial concentration of polyphenols of the C.nutans extracts impregnated in the alginate aerogels is stable in the range of 0.796 to 0.745 mg/g in 6 month and drastically reduced after 9 month of storage duration. The herbal extract type C.nutans-100 loaded via supercritical CO2 impregnation has a comparable specific loading to the method of liquid media, range from 1.4 to 1.5 × 10 g/m whereas the specific loading of C.nutans-50 extract impregnated via liquid media showed higher compared with the loading by method of supercritical CO2.