Fabrication and characterization of carboxymethylated bael fruit gum with potential mucoadhesive applications

Abstract

A study was conducted to enhance the mucoadhesive potential of bael fruit gum by carboxymethylation. Carboxymethylation of bael fruit gum was achieved through its reaction with monochloroacetic acid in the presence of sodium hydroxide as a catalyst under different reaction conditions. The optimal degree of substituted carboxymethyl in the carboxymethylated bael fruit gum was found to be 0.68. The resulting product was characterized by FT-IR, DSC, XRD and SEM analyses. The results revealed that the carboxymethylated derivative of bael fruit gum showed an improved mucoadhesive potential compared to unmodified gum, with a slightly increased degree of crystallinity, surface roughness and decreased viscosity. Additionally, metformin-loaded, ionotropically gelled beads of bael fruit gum and carboxymethylated bael fruit gum were formulated using calcium chloride as a cross-linking agent. An ex vivo bioadhesion study performed by a wash-off test using goat intestinal mucosa showed higher bioadhesion times for carboxymethylated bael fruit gum compared to bael fruit gum. In vitro release studies conducted using phosphate buffer (pH 6.8) showed a faster release of metformin from carboxymethylated bael fruit gum than from bael fruit gum. These results have demonstrated that carboxymethylated bael fruit gum is a promising mucoadhesive excipient.