Drug release properties of sodium alginate hydrophobically modified by star polylactic acid

Inorganic/polymer hybrid star polylactic acid (POSS-PLA) was obtained through ring-opening polymerization of lactide by using polyhydroxyl cage silsesquioxane (POSS-OH) as the core and tin (II) octoate as the catalyst.  The star polylactic acid (POSS-PLA) was used to modify sodium alginate hydrophobically and a drug carrier was obtained.  The drug release behavior was investigated by using ibuprofen as the model drug.  The results showed that the drug loading rate could be improved and the release rate was postponed with an   increase of POSS-PLA content in the carries.  The release mechanism gradually changed from the first-order to the zero-order pattern after the modification.