A composite material with improved sustained release properties
based on hybridization of sodium alginate (SA) and acidified-attapulgite (H+-ATP)
was prepared by solution mixing and was developed for drug carrier. Diclofenac sodium (DS) was selected as the model drug to obtain release data from the composite-based matrix tablets in phosphate buffer solution (PBS) in vitro. The morphology and structure of the composite were characterized by FTIR
SEM and XRD. The effect of content of acid modifier
H+-ATP content and mixing time on the slow release properties of the composite were investigated to obtain optimum process condition. The composite with 60% H+-ATP treated by 12 mol·L-1 HCl exhibited perfect release properties. Compared with pure alginate tablets
the burst release of 42.6 % in 2 h decreased to 23.7% for the prepared composite. The drug release process of the composite was better fitted by the Ritger-Peppas model and the rate of drug release was governed by both diffusion and swelling mode. The introduced H+-ATP improved the release properties of alginate significantly.