Designing calcium phosphate-based bifunctional nanocapsules with bone-targeting properties

  • Yit-Lung Khung
  • Kelsen Bastari
  • Xing Ling Cho
  • Wu Aik Yee
  • Say Chye Joachim LooEmail author
Research Paper


Using sodium dodecyl sulphate micelles as template, hollow-cored calcium phosphate nanocapsules were produced. The surfaces of the nanocapsule were subsequently silanised by a polyethylene glycol (PEG)-based silane with an N-hydroxysuccinimide ester end groups which permits for further attachment with bisphosphonates (BP). Characterisations of these nanocapsules were investigated using Field Emission Scanning Electron Microscopy (FESEM), Transmission Electron Microscopy, Fourier Transform Infra-Red Spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy and Dynamic Light Scattering. To further validate the bone-targeting potential, dentine discs were incubated with these functionalised nanocapsules. FESEM analysis showed that these surface-modified nanocapsules would bind strongly to dentine surfaces compared to non-functionalised nanocapsules. We envisage that respective components would give this construct a bifunctional attribute, whereby (1) the shell of the calcium phosphate nanocapsule would serve as biocompatible coating aiding in gradual osteoconduction, while (2) surface BP moieties, acting as targeting ligands, would provide the bone-targeting potential of these calcium phosphate nanocapsules.


Micelle Calcium phosphate Bisphosphonate Osteomyelitis Drug delivery Bone-targeting Nanomedicine 


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Copyright information

© Springer Science+Business Media B.V. 2012

Authors and Affiliations

  • Yit-Lung Khung
    • 1
  • Kelsen Bastari
    • 1
  • Xing Ling Cho
    • 1
  • Wu Aik Yee
    • 1
  • Say Chye Joachim Loo
    • 1
    Email author
  1. 1.School of Materials Science and EngineeringNanyang Technological UniversitySingaporeSingapore

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