Evaluation of Cassia fistula seed galactomannan as tablet-binder in formulation of diclofenac sodium-loaded monolithic matrix tablet

The present study aimed to evaluate Cassia fistula seed galactomannan (CFSG) as a tablet-binder in the formulation of a monolithic matrix tablet using diclofenac sodium as a model drug. Initially, CFSG was extracted and purified from the seeds of the Cassia fistula tree and then screened for phytochemicals. Native CFSG was characterized with polysaccharide content determination, monosaccharide composition analysis, elemental analysis, FTIR, solid-state 13C NMR, molecular weight, zeta potential, DSC, TGA-DTA, XRD, viscosity, pH and surface tension, rheology, SEM and acute oral toxicity study. Prior to formulation, the drug-CFSG compatibility was checked by FTIR, DSC, and XRD. Diclofenac sodium-loaded granules were prepared by the wet granulation method and evaluated for various granule properties. Finally, granules were compressed into tablets and evaluated for binding and other tablet properties. The granules showed to have optimum micromeritic properties. Tablet hardness and friability were found to be approximately 7 kg/m2 and 0.3 %, respectively, which substantiate the excellent binding capacity of CFSG. Other tablet properties were also found to be within the Pharmacopoeial compliance limit. The tablets with a minimum concentration of CFSG (2.5%w/w) as binder showed appreciable mechanical strength and faster drug release, which ratifies CFSG as an alternative tablet binder.