Formulation Development and Characterization of Vancomycin Hydrochloride Colon-Targeted Tablets Using In-Situ Polyelectrolyte Complexation Technique

Abstract

Introduction: Vancomycin hydrochloride (VH) is an amphoteric glycopeptide antibiotic used to manage enterocolitis and pseudomembranous colitis. However, VH is prone to proteolytic degradation in the stomach, thus obscuring the drug entry into the colon. Colon-targeted drug delivery can prevent gastric degradation and localise the drug in the colon. 

Methodology: The applicability of in situ polyelectrolyte complexation technique using the polymers Chitosan, Karaya gum, and Hupu gum at various concentrations along with enteric coating using Eudragit S100 was studied for the preparation of colon-targeted tablets of VH.

Colon-targeted tablets of VH are developed by incorporating natural polymers like chitosan, karaya gum, and hupu gum at different concentrations such that in-situ polyelectrolyte complex is formed and the formulations were then coated with Eudragit S100(6%, 8%, and 10% weight gain) to release the drug in a controlled manner in the colon. 

Results: Prepared formulations were subjected to in vitro, ex vivo, and in vivo evaluation studies. Out of all the prepared formulations, the formulation H2C10 prepared with 10:2 PEC and 10% Eudragit S100 coating has shown a sufficient lag time of 2 hours in 0.1N HCl, 3 hours of lag time in pH 6.8 phosphate buffer and has shown a 100.02% drug release at 22 hours in pH 7.4 phosphate buffer. 

Conclusion: The research results suggested that a colon-targeted drug delivery system of VH can decrease drug degradation and achieve higher concentrations in the colon to provide more therapeutic benefits.