Design and Evaluation of Oral Dissolving Films of Chlorpheramine From Native and Modified Enterolobium cyclocarpum   Gum

Pharmaceutical excipients of natural origin have numerous advantages which include biocompatibility, non toxicity and biodegradability. Selection of a suitable film-forming polymer is important in the formulation of oral fast dissolving films. This work aims to investigate a natural gum from Enterolobium cyclocarpum tree, as a film forming polymer in chlorpheniramine oral film formulations; comparing it with hydroxylpropylmethyl cellulose (HPMC). Enterolobium gum was modified, using acetic anhydride (acetylation) and ethylene glycol. Physicochemical properties of native and modified gums were determined. Oral dissolving films were prepared from blends of HPMC and either native, acetylated or ethylene glycol modified gum, using the solvent evaporation technique. Films were evaluated for weight variation, thickness, folding endurance, in-vitro disintegration and release properties. FT-IR revealed no adverse chemical interaction. High moisture content was shown by the swelling index determination; acetic anhydride modified gum had the highest (p<0.05). The gums were of neutral pH, the modification methods significantly reduced viscosity of the gum. Native and modified gums produced films of acceptable qualities. Modification by acetylation produced films with better mechanical properties. Films produced with blends of native gum/HPMC and acetylated gum/HPMC had better release profile than those produced by HPMC. Drug release from the films improved with increasing concentration of the gum, up to an optimum gum/HPMC blend ratio of 2:3. Physicochemical properties of Enterolobium gum improved by gum modification. Enterolbium gum proved to be a suitable polymer in chlorpheniramine oral dissolving films. Modification by ethylene glycol produced films with best drug release profile.

Keywords
Oral dissolving films; Enterolobium gum; Chlorpheniramine; Natural polymer