Effect of sepiolite on the physical properties and swelling behavior of rifampicin-loaded nanocomposite hydrogels

Nanocomposite hydrogels based on poly(vinyl alcohol) - PVA and sepiolite have been prepared and their poten- tial for drug delivery systems has been assessed by taking rifampicin as model drug. The nanocomposite hydrogels were characterized by WAXS and DSC and the swelling behavior and structural stability were evaluated. The effect of the pres- ence of rifampicin, sepiolite and simultaneous rifampicin-sepiolite on the structure and swelling of the hydrogels was inves- tigated. The swelling data were analyzed in order to evaluate the diffusion mechanisms of water. The results indicate that both rifampicin and sepiolite cause important modifications on microstructure of the PVA matrix, leading to changes on swelling and diffusional behavior.