DEVELOPMENT AND OPTIMIZATION OF CHITOSAN-CA-PECTINATE BEADS OF AMORPHOUS CELECOXIB BY RESPONSE SURFACE METHODOLOGY

The aim of the present work was to develop a new microbeads system for colon-targeted delivery of celecoxib. The ternary system were develop using PVP (polyvinylpyrrolidone) and hydroxypropyl-β-cyclodextrin (HPB) to increase solubility of celecoxib.  DSC and XRD results confirmed formation of amorphous celecoxib complex with HPB. Chitosan and pectin were used for the development of microbeads of new amorphous celecoxib. Calcium chloride was use as cross linking agent for electrolyte complexation between polymers. Eudragit RS100 was used to embed into microbeads in order to avoid premature delivery of a drug in acidic environment of stomach. Statistical design of experiment was employed to investigate the combined effect of three formulation variables, i.e., % of chitosan, pectin, and CaCl₂, on responses like drug release pattern in acidic dissolution medium (CDR in UGIT), colonic dissolution medium with fungus culture of Aspergillus niger (CDR in LGIT) and drug entrapment efficiency (EE%). Response surface methodology was used to analyze multivariate approach for understanding the multifactorial relationships among formulation parameters. Full central composite design was employed to define a design space. Desirability was used to attain simultaneous optimization of responses. Optimized formulation were evaluated and it was then found that obtained experimental values very close to predicted values. Eudragit RS 100 was successfully embedded in mocrobeads because there was negligible drug loss in acidic environment and maximum drug was released in colonic medium.