Film-forming And Property Evaluation Of Algal Polysaccharide Composite Gel

Algal polysaccharide composite gel is a type of plant gel containing mainly algal polysaccharide extracted from marine Rhodophyte and plant cellulose. It can be directly used in China Pharmaceutical Excipients-hollow capsule industry as a viable alternative to gelatin, which may promote high value utilization and improve the overall technical level of the capsule industry.Viscosity, gelation behavior and rheological properties of algal polysaccharide and plant cellulose have been studied respectively. A composite plant gel with good rheological properties and gel point is obtained when mix the two materials in certain proportion.The film-forming performance of the composite gel has been studied by the well-known dipping technique as used in the manufacture of conventional gelatin capsule. Determined by different technical parameters,we obtain a plant compound film with thickness less than 0.1mm which compliant with the state requirements of hollow capsule thickness. The disintegration time, dry weight loss and other indicators also show that the quality of this film fully comply the quality standards of State Food and Drug Administration (SFDA).In vivo and in vitro medical indicators of the compound film have been evaluated compared with animal gelatin film and other plant films. The final in vitro dissolution rates of two kinds of model drug filled in the compound film were 99.84% and 98.29% respectively. Both are in line with national standards (>70%). In vivo ?-scintigraphy studies show that the mean disintegration time of the compound film in stomach is 9.5±4.0min, almost the same with Japanese Qualicaps film. Bioavailability studying shows that there are no statistically significant differences between the compound film and gelatin film in AUC values and the results demonstrate that the two preparations are bioequivalent.In conclusion, the plant compound film formed by algal polysaccharide and plant cellulose reaches the standards of SFDA; In vivo and in vitro studies show that the film is comparable with other similar plant films and gelatin film. Therefore, it offers a practical alternative to gelatin in hollow capsule industry.