Fabrication of Interpenetrating Polymer Network-based Hydrogel for Colon-specific Release of Lercanidipine Hydrochloride

Lercanidipine hydrochloride is a potent antihypertensive agent which suffers from the drawback of extensive first-pass metabolism making it an ideal candidate for incorporation into hydrogels with a site-specific release. The current paper explores the preparation, characterization and evaluation of interpenetrating polymer networks composite hydrogels of chitosan and poly (meth(methacrylic)) acid as a potential carrier for the drug. Interpenetrating polymer networks composite hydrogels of chitosan and poly (meth(methacrylic)) acid incorporating lercanidipine hydrochloride were prepared using N,Nꞌ-methylene bisacrylamide and glutaraldehyde as cross-linkers. The polymerization of chitosan, entrapment of the drug and its interaction in prepared hydrogels were checked by Fourier Transform Infra-Red spectroscopy, Differential Scanning Calorimetry and powder X-Ray Diffractometry studies, which confirmed the formation of the polymer and absence of any significant chemical change in the drug after being entrapped in crosslinked hydrogel formulations. The hydrogels were evaluated for their swelling behavior and in vitro drug release. The morphology of the hydrogels before and after the dissolution was studied using Scanning Electron Microscopy. The hydrogels showed more than 92.17 ± 3.68% yield and 91.33 ± 3.18% drug loading. The hydrogels exhibited pH-sensitive swelling behavior with very less swelling in an acidic environment and quick swelling in an alkaline environment. In vitro release profile confirmed that the drug release was found to depend on swelling of hydrogels and showed a biphasic release pattern with non-Fickian diffusion kinetics at higher pH. The surface morphology of the optimized formulation revealed large open channel-like pores formation after dissolution. Chitosan-poly (meth(methacrylic)) acid interpenetrating polymer network hydrogel with its biodegradable nature and pH-sensitive release of lercanidipine hydrochloride is an attractive option to be further explored for targeted controlled drug delivery formulations for the drug.