Chitosan adsorption on hydroxyapatite and its role in preventing acid erosion

Hyun Su Lee, Shannon Tsai, Chin Chen Kuo, Alice W. Bassani, Brian Pepe-Mooney, Davide Miksa, James Masters, Richard Sullivan, Russell J. Composto

Research output: Contribution to journalArticlepeer-review

49 Scopus citations


Polymer adsorption onto an artificial saliva (AS) layer is investigated using quartz-crystal microbalance with dissipation (QCM-D) and chitosan as the model polymer. QCM-D is utilized in an innovative manner to monitor in situ adsorption of chitosan (CH) onto a hydroxyapatite (HA) coated crystal and to examine the ability of the adsorbed layer to " protect" the HA upon sequential exposure to acidic solutions. After deposition of a thin AS layer (16. nm), the total thickness on the HA substrate increases to 37. nm upon exposure to CH at pH 5.5 for 10. min. Correspondingly, the surface charge changes from negative (i.e., AS) to positive, consistent with the adsorption the polycationic CH onto or into the AS layer. Upon exposure to an oxidizing agent, the chitosan cross-links and collapses as noted by a decrease in thickness to 10. nm and an increase in the shear modulus by an order of magnitude. Atomic force microscopy (AFM) is used to determine the surface morphology and RMS roughness of the coated and HA surfaces after citric acid challenges. Both physisorbed and cross-linked chitosan are demonstrated to limit and prevent the erosion of HA, respectively.

Original languageEnglish
Pages (from-to)235-243
Number of pages9
JournalJournal of Colloid and Interface Science
Issue number1
StatePublished - 1 Nov 2012
Externally publishedYes


  • AFM
  • Acid erosion
  • Atomic force microscopy
  • Chitosan
  • HA
  • Hydroxyapatite
  • In situ quartz-crystal microbalance with dissipation
  • Polymer adsorption
  • QCM-D


Dive into the research topics of 'Chitosan adsorption on hydroxyapatite and its role in preventing acid erosion'. Together they form a unique fingerprint.

Cite this