Chitosan/polyethylene glycol beads crosslinked with tripolyphosphate and glutaraldehyde for gastrointestinal drug delivery

AAPS PharmSciTech. 2010 Sep;11(3):1128-37. doi: 10.1208/s12249-010-9483-z. Epub 2010 Jul 22.

Abstract

This study reports on the preparation of chitosan (CS)/polyethylene glycol (PEG) hydrogel beads using sodium diclofenac (DFNa) as a model drug. Following the optimization of the polymer to drug ratio, the chitosan beads were modified by ionic crosslinking with sodium tripolyphosphate (TPP). The CS/PEG/DFNa beads obtained from a (w/w/w) ratio of 1/0.5/0.5 with crosslinking in 10% (w/v) TPP at pH 6.0 for 30 min yielded excellent DFNa encapsulation levels with over 90% loading efficiency. The dissolution profile of DFNa from CS/PEG/DFNa beads demonstrated that this formulation was able to maintain a prolonged drug release for approximately 8 h. Among the formulations tested, the CS/PEG/DFNa (1/0.5/1 (w/w/w)) beads crosslinked with a combination of TPP (10% (w/v) for 30 min) and glutaraldehyde (GD) (5% (w/v)) were able to provide minimal DFNa release in the gastric and duodenal simulated fluids (pH 1.2 and 6.8, respectively) allowing for a principally gradual drug release over 24 h in the intestinal (jejunum and ileum) simulated fluid (pH 7.4). Thus, overall the CS/PEG beads crosslinked with TPP and GD look to be a promising and novel alternative gastrointestinal drug release system.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Chitosan / chemistry*
  • Cross-Linking Reagents / chemistry
  • Delayed-Action Preparations / administration & dosage*
  • Delayed-Action Preparations / chemistry
  • Diffusion
  • Gastrointestinal Agents / administration & dosage
  • Gastrointestinal Agents / chemistry*
  • Gastrointestinal Contents / chemistry
  • Glutaral / chemistry*
  • Humans
  • Microspheres
  • Polyethylene Glycols / chemistry*
  • Polyphosphates / chemistry*

Substances

  • Cross-Linking Reagents
  • Delayed-Action Preparations
  • Gastrointestinal Agents
  • Polyphosphates
  • Polyethylene Glycols
  • Chitosan
  • triphosphoric acid
  • Glutaral