Abstract

EVALUATION OF DRUG RELEASE FROM HPMC CARBOXYMETHYL GUAR GUM MATRICES

Deepak Kumar Kushawah, Mohd. Junaid*, Pawan Singh and Shane Alam

ABSTRACT

The objective of present work was to study the feasibility of modified Guar gum - HPMC K4 M polymeric matrices as carrier for sustained stomach specific delivery of highly water soluble model drug, Verapamil HCl. Two types of modifications were carried out on native Guar gum. physical and chemical. In case of physical modification, Guar gum dispersions were exposed to microwave radiation, whereas, in case of chemical modification, carboxymethyl Guar gum was prepared using Williamson synthesis. The prepared modified Guar gum samples were characterized by FTIR for the evidence of carboxymethylation (in case of chemical modification) and molecular integrity (in case of physical modification). The prepared modified Guar gum samples were than combined with HPMC K4M and model drug followed by encapsulation in hard gelation capsules. The prepared hydrodynamically balanced (HBS) capsule dosage forms were than evaluated for in vitro buoyancy and drug release studies in 0.1 M HCl. The HBS formulations based on modified Guar gum-HPMC K4M exhibited excellent in vitro buoyancy (24 h) and were capable of sustaining the drug release for prolonged period. The drug release followed Korsmeyer-Peppas kinetics for chemically modified guar gum-HPMC K4M matrices and Zero order from physically modified Guar gum HPMC K4M matrices. Overall it may be concluded that modified guar gum-HPMC K4M matrices may constitute interesting polymeric carriers for sustained stomach specific release of drugs with absorption window in upper GIT.

Keywords: Guar gum – HPMC K4 M, Verapamil HCl, 0.1 M HCl.