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Drug release behavior of chitosan–montmorillonite nanocomposite hydrogels following electrostimulation

Paper ID Volume ID Publish Year Pages File Format Full-Text
2116 100 2008 8 PDF Available
Title
Drug release behavior of chitosan–montmorillonite nanocomposite hydrogels following electrostimulation
Abstract

Nanocomposites hydrogel (nanohydrogel) composed of chitosan (CS) and montmorillonite (MMT) were prepared and systematically studied for drug release behavior following electrostimulation. The deterioration of the responsiveness and reversibility of CS upon repeated on–off electrostimulation switching operations are major limitations for clinical applications, as it suffers from too much structural instability for the precise control of the release of drug upon cyclic electrostimulation. To overcome these limitations, an inorganic phase, MMT, was incorporated in the CS matrix to enhance the anti-fatigue property and corresponding long-term stable release kinetics. X-ray diffraction analysis and time-dependent optical absorbance showed that the MMT incorporated into the nanohydrogel exhibited an exfoliated nanostructure. The exfoliated silica nanosheets are able to act as cross-linkers to form a network structure between the CS and MMT, and this difference in the cross-linking density strongly affects the release of vitamin B12 under electrostimulation. With a lower MMT concentration (1 wt.%), the release kinetics of vitamin B12 from the nanohydrogel shows a pseudo-zero-order release, and the release mechanism was changed from a diffusion-controlled mode to a swelling-controlled mode under electrostimulation. Further increasing the MMT content reduced both the diffusion exponent n and the responsiveness of the nanohydrogel to electrostimulation. In addition, a consecutively repeated “on” and “off” operation shows that the electroresponsiveness of the nanohydrogel with higher MMT concentrations was reduced, but its anti-fatigue behavior was considerably improved. In this work, the nanohydrogel with 2 wt.% MMT achieved a mechanically reliable and practically desirable pulsatile release profile and excellent anti-fatigue behavior, compared with that of the pure CS.

Keywords
Chitosan; Montmorillonite; Nanocomposite hydogel; Electrostimulation controlled release; Anti-fatigue
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Drug release behavior of chitosan–montmorillonite nanocomposite hydrogels following electrostimulation
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Publisher
Database: Elsevier - ScienceDirect
Journal: Acta Biomaterialia - Volume 4, Issue 4, July 2008, Pages 1038–1045
Authors
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Subjects
Physical Sciences and Engineering Chemical Engineering Bioengineering
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us