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AAPS PharmSciTech. 2006 June; 7(2): E138–E143.
Published online 2006 April 9. doi:  10.1208/pt070250
PMCID: PMC2750277

Studies on effect of pH on cross-linking of chitosan with sodium tripolyphosphate: A technical note

Summary and Conclusions

The ionotropic gelation method for formation of crosslinked chitosan particles can be easily modified from ionic cross-linking to deprotonation by adjusting the pH of TPP. Chitosan was cross-linked ionically with TPP at lower pH and by deprotonation mechanism at higher pH. The swelling behavior of cross-linked chitosan appeared to depend on the pH of TPP. The ionically cross-linked chitosan showed higher swelling ability. Thus the nature of crosslinked chitosan can be tailor made to obtain the desired properties in terms of cross-linking density, crystallinity, and hydrophilicity.

Keywords: chitosan, deprotonation, ionic cross-linking, mechanistic study, tripolyphosphate

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.
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