A pH/enzyme-responsive polymer film consisting of Eudragit® FS 30 D and arabinoxylane as a potential material formulation for colon-specific drug delivery system

Polymer film based on pH-dependent Eudragit (R) FS 30 D acrylic polymer in association with arabinoxylane, a polysaccharide issued from gum psyllium, was produced by way of solvent casting. Physical-chemical characterization of the polymer film samples was performed by means of thermogravimetry (TGA), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). Furthermore, water-equilibrium swelling index (Is) and weight loss of the films in KCl buffer solution of pH 1.2, in KH2PO4 buffer solution of pH 5.0, or in KH2PO4 buffer solution of pH 5.0 consisting of 4% enzyme Pectinex (R) 3X-L (w/v) were also carried out for the film characterization. No chemical interactions between the Eudragit (R) FS 30 D and the arabinoxylane polymer chains were evidenced, thus suggesting that the film-forming polymer structure was obtained from a physical mixture of both polymers. The arabinoxylane-loader films showed a more pronounced weight loss after their immersion in buffer solution containing enzyme Pectinex (R) 3X-L. The introduction of the arabinoxylane makes the film more susceptible to undergo an enzymatic degradation. This meant that the enzyme-dependent propriety issued from the arabinoxylane has been imprinted into the film formulation. This type of polymer film is an interesting system for applications in colon-specific drug delivery system.