Silica nanoparticles carrying boron-containing polymer brushes

  • Eric M. Brozek
  • Alexis H. Mollard
  • Ilya Zharov
Research Paper


A new class of surface-modified silica nanoparticles has been developed for potential applications in boron neutron capture therapy. Sub-50 nm silica particles were synthesized using a modified Stöber method and used in surface-initiated atom transfer radical polymerization of two biocompatible polymers, poly(2-(hydroxyethyl)methacrylate) and poly(2-(methacryloyloxy)ethyl succinate). The carboxylic acid and hydroxyl functionalities of the polymeric side chains were functionalized with carboranyl clusters in high yields. The resulting particles were characterized using DLS, TEM, solution 1H NMR, solid state 11B NMR and thermogravimetric analysis. The particles contain between 13 and 18 % of boron atoms by weight, which would provide a high amount of 10B nuclides for BNCT, while the polymer chains are suitable for further modification with cell targeting ligands.


Silica Nanoparticles Carboranes Polymer brushes Non-toxic particles in biological systems 



This work was supported by the University of Utah Research Foundation through a Seed Grant and by the National Science Foundation (DMR-1008251). We are grateful to James K. Harper (University of Utah) for recording solid state NMR spectra.


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Copyright information

© Springer Science+Business Media Dordrecht 2014

Authors and Affiliations

  • Eric M. Brozek
    • 1
  • Alexis H. Mollard
    • 1
  • Ilya Zharov
    • 1
  1. 1.Department of ChemistryUniversity of UtahSalt Lake CityUSA

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