Formulation and evaluation of biopolymers based Drug Delivery Systems

Abstract

Pharmaceutical polymers are widely used to achieve taste masking; thickening (rheology modifier), gelling (controlled release), adhesion (binding), pH-dependent solubility (controlled release), controlled release (e.g., extended, pulsatile, and targeted), barrier properties (protection and packaging), enhanced stability, and improved bioavailability. Natural polysaccharides hold advantages over synthetic polymers because they are non toxic, less expensive and easily available. Natural polymers can be tailor-made for preparing drug delivery systems and thus can compete with synthetic biodegradable materials available in the market. Hence, there is a need to develop new carriers which are safe, economical and non toxic. Here, an attempt is being made for the use of natural polymers, kondagugu gum and ghatti gum as carrier/ excipient for formulation of different drug delivery systems. The aim of first study was to formulate and evaluate conventional tablets using natural, biodegradable polymers like kondagogu gum and ghatti gum. Granules were prepared for metoprolol tartarate employing kondagogu gum and ghatti gum as binders. The granules were evaluated for moisture content, angle of repose, density, Carr s index, Hausner ratio, particle size distribution and surface morphology by SEM. The granules were then compressed into tablets using a tablet compression machine and evaluated for parameters like hardness, thickness, weight variation, percent friability, disintegration and drug content. The percentage weight variation, percent friability and content of active ingredient for all the formulations were found to be well within United States Pharmacopoeia (USP) standards. The tablets prepared with kondagogu gum and ghatti gum as binders showed hardness in the range 1.8-9.1 and 2.2-10.1 Kg respectively.