Synthesis and characterization of kappa-carrageenan-based magnetic nanocomposite hydrogels for pH-sensitive delivery of diclofenac and ibuprofen

In this study, nanocomposite hydrogels composed of κ-carrageenan (κ-CG), Fe₃O₄ magnetic nanoparticles, and Cu-Co layered double hydroxides (LDH) were prepared as pH-sensitive drug delivery systems for the loading and controlled release of Diclofenac and Ibuprofen. Potassium Chloride (KCl) was used as a physical crosslinking agent. The prepared nanocomposite hydrogel beads were characterized by FT-IR, XRD, SEM, EDX-mapping, and VSM methods. The drug release and swelling behavior of these hydrogels have been studied in buffer solutions of different pH (1.2, 5.4, 6.8, and 7.4). In addition, to investigate the drug release mechanisms, different models were studied. The in-vitro drug release and kinetics analysis revealed that the κ-CG/Fe₃O₄/Cu-Co-LDH exhibited enhanced performance in acidic (stomach-like) pH conditions and enhances drug dosing stability through controlled release. The swelling results showed that the effect of pH on the swelling of hydrogels was not statistically significant, but the effect of the type of carrier, in other words, the addition of Fe₃O₄ nanoparticles and Cu-Co LDH, on the swelling of hydrogels was significant (at 95 %).