Ex-vivo evaluation of crab shell chitosan as absorption enhancer in ciprofloxacin tablet formulation
This study was aimed at evaluating crab shell chitosan as absorption enhancer in ciprofloxacin tablet formulation using the ex-vivo model. Six batches of ciprofloxacin tablets containing varying concentrations of crab shell-derived chitosan ranging from 0 to 5% w/w at 1% w/w intervals were produced. Batch CTS-0 containing no chitosan served as the control. The crushing strength, friability, disintegration time, dissolution profile and permeation profile of all the batches were determined. Friability was not significantly affected but the crushing strength and disintegration time of tablets decreased with increase in concentration of chitosan. There was no significant difference in the cumulative percent drug released in 1 h but the cumulative percent drug permeated in 4 h increased with increase in the concentration of chitosan. It increased from 68% (when no chitosan was added) to 81.8% (when 5% w/w chitosan was incorporated). The polymer caused a faster onset of drug release but the eventual total drug released was not significantly influenced. It also improved the permeation of the released drug. This study correlates with in-vivo bioavailability study because the usual oral bioavailability of ciprofloxacin without absorption enhancer is 70%. Hence, crab shell chitosan at concentration of 5% w/w could increase the absorption of ciprofloxacin from 70 to 82%. The study suggests the use of the chitosan at this concentration to improve the absorption of ciprofloxacin.
Key words: Crab shell chitosan, ciprofloxacin, dissolution, permeation, absorption.