FLOATING-BIOADHESIVE MATRIX TABLETS OF HYDRALAZINE HCL MADE OF CASHEW GUM AND HPMC K4M

Abstract

Objective: The objective of this paper was to prepare and evaluate floating-bioadhesive cashew gum-hydroxypropyl methylcellulose (HPMC K4M) matrix tablets for the gastro-retentive release of hydralazine HCl.Methods: The cashew gum-HPMC K4M matrix tablets of hydralazine HCl were prepared by direct compression method with the incorporation of sodium bicarbonate and citric acid as effervescent agents. Drug contents, weight variations, hardness, friability, in vitro swelling, in vitro floatation, ex vivo mucoadhesion and in vitro drug release of these matrix tablets were evaluated.Results: Drug contents, weight variations, hardness and friability of these matrix tablets were within the compendia limits. These tablets were floated well in vitro over 12 h in simulated gastric fluid (SGF, pH 1.2) with minimum lag time. The ex vivo adhesion of these matrix tablets with goat intestinal mucosa exhibited good bioadhesion in a wash off test. All these cashew gum-HPMC K4M floating-bioadhesive matrix tablets of hydralazine HCl showed in vitro sustained releases of hydralazine HCl over 12 h in SGF, pH 1.2. The in vitro hydralazine HCl followed Korsmeyer-Peppas kinetic model and anomalous (non-Fickian) diffusion mechanism. The drug-polymer compatibility analysis by FTIR spectroscopy indicated the absence of any drug-polymer interaction within this cashew gum-HPMC K4M floating-bioadhesive matrix tablets of hydralazine HCl.Conclusion: The results clearly indicate a promising potential of the use of cashew gum as matrix forming a material with HPMC K4M to prepare matrix tablets for gastro retentive delivery of hydralazine HCl through the combined approach of floatation and bioadhesion to reduce the dosing rate with better patient compliances.