Novel pH sensitive composite hydrogel based on functionalized chitosan/clay for the controlled release of a calcium channel blocker

Abstract

The concept of novel drug delivery systems aims at achieving systematically improved therapeutic success for drugs including those that have limited use because of toxicity, uneven distribution pattern, stability and formulation of difficulties. The paper reveals the potential uses of novel hybrids of oleic acid-g-chitosan and montmorillonite (OA-g-CS/MMT) in controlled drug delivery applications. A calcium channel blocker is a chemical that disrupts the movement of calcium (Ca2+) through calcium channels. The calcium channel blocker used for the present investigation is diltiazem hydrochloride, which forms a class three antianginal drug, and a class IV antiarrhythmic. The drug-loaded novel composites have been prepared by solvent casting and freeze drying of the grafted polymer solution. Drug release was monitored by changing time, percentage of drug loading and pH of the medium. It was observed that the release was much more pronounced in the basic medium than in the acidic medium. The maximum release of drug from OA-g-CS/MMT in both gastric and intestinal fluids was observed within a time period of 12 h.