Effects of intercalated hydrotalcite on drug release behavior for poly(acrylic acid-co-N-isopropyl acrylamide)/intercalated hydrotalcite hydrogels

The influence of positively charged intercalated hydrotalcite (IHT) in the anionic poly(acrylic acid-co-N-isopropyl acrylamide), poly(AA-co-NIPAAm)/hydrotalcite nanocomposite hydrogels on the drug release behavior for the drugs with different charges was investigated in this study. Results show that the loading amount and release ratio of indomethacin are affected by the swelling ratio in saline solution and related to the affinity in the alcohol solution, respectively. The loading amount and release ratio of caffeine are affected by the swelling ratio. The loading amount of crystal violet (CV) increased with an increase of the content of intercalating agent in IHT of the gel but the fractional release of CV in the gels decreases with increase in intercalating agent content. The result of release and loading for phenol red in the hydrogels is contrary to CV. (c) 2006 Elsevier Ltd. All rights reserved.