Nano Research

, Volume 2, Issue 7, pp 583–591 | Cite as

Rattle-type silica colloidal particles prepared by a surface-protected etching process

  • Qiao Zhang
  • Jianping Ge
  • James Goebl
  • Yongxing Hu
  • Zhenda Lu
  • Yadong Yin
Open Access
Research Article

Abstract

This paper explores the capability of the “surface-protected etching” process for the creation of rattle-type SiO2@void@SiO2 colloidal structures featuring a mesoporous silica shell and a mesoporous movable silica core. The surface-protected etching process involves stabilization of the particle surface using a polymer ligand, and then selective etching of the interior to form hollow structures. In this paper, this strategy has been extended to the formation of rattle-like structures by etching SiO2@SiO2 core shell particles which are synthesized by a two-step sol gel process. The key is to introduce a protecting polymer of polyvinylpyrrolidone (PVP) to the surface of both core and shell in order to tailor their relative stability against chemical etching. Upon reacting with NaOH, the outer layer silica becomes a hollow shell as only the surface layer is protected by PVP and the interior is removed, while the core remains its original size thanks to the protection of PVP on its surface. This process can be carried out at room temperature without the need of additional templates or complicated heterogeneous coating procedures. The etching process also results in the rattle-type colloids having mesoscale pores with two distinct average sizes. In our demonstration of a model drug delivery process, such mesoporous structures show an interesting two-step elution profile which is believed to be related to the unique porous rattle structures.

Keywords

Silica mesoporous core-shell structure surface-protected etching drug delivery 

References

  1. [1]
    Sun, X. M.; Liu, J. F.; Li, Y. D. Oxides@C core-shell nanostructures: One-pot synthesis, rational conversion, and Li storage property. Chem. Mat. 2006, 18, 3486–3494.CrossRefGoogle Scholar
  2. [2]
    Zhang, L.; Tu, R.; Dai, H. J. Parallel core-shell metal-dielectric-semiconductor germanium nanowires for high-current surround-gate field-effect transistors. Nano Lett. 2006, 6, 2785–2789.CrossRefPubMedADSGoogle Scholar
  3. [3]
    Xie, R. G.; Chen, K.; Chen, X. Y.; Peng, X. G. InAs/InP/ZnSe core/shell/shell quantum dots as near-infrared emitters: Bright, narrow-band, non-cadmium containing, and biocompatible. Nano Res. 2008, 1, 457–464.CrossRefGoogle Scholar
  4. [4]
    Wan, Y.; Min, Y. L.; Yu, S. H. Synthesis of silica/carbon-encapsulated core-shell spheres: Templates for other unique core shell structures and applications in in situ loading of noble-metal nanoparticles. Langmuir 2008, 24, 5024–5028.CrossRefPubMedGoogle Scholar
  5. [5]
    Kamata, K.; Lu, Y.; Xia, Y. N. Synthesis and characterization of monodispersed core-shell spherical colloids with movable cores. J. Am. Chem. Soc. 2003, 125, 2384–2385.CrossRefPubMedGoogle Scholar
  6. [6]
    Lou, X. W.; Archer, L. A.; Yang, Z. C. Hollow micro-/nanostructures: Synthesis and applications. Adv. Mater. 2008, 20, 3987–4019.CrossRefGoogle Scholar
  7. [7]
    Zhang, Q.; Zhang, T. R.; Ge, J. P.; Yin, Y. D. Permeable silica shell through surface-protected etching. Nano Lett. 2008, 8, 2867–2871.CrossRefPubMedADSGoogle Scholar
  8. [8]
    Sun, Y. G.; Wiley, B.; Li, Z. Y.; Xia, Y. N. Synthesis and optical properties of nanorattles and multiple-walled nanoshells/nanotubes made of metal alloys. J. Am. Chem. Soc. 2004, 126, 9399–9406.CrossRefPubMedGoogle Scholar
  9. [9]
    Yin, Y. D.; Rioux, R. M.; Erdonmez, C. K.; Hughes, S.; Somorjai, G. A.; Alivisatos, A. P. Formation of hollow nanocrystals through the nanoscale Kirkendall effect. Science 2004, 304, 711–714.CrossRefPubMedADSGoogle Scholar
  10. [10]
    Lee, J.; Park, J. C.; Song, H. A nanoreactor framework of a Au@SiO2 yolk/shell structure for catalytic reduction of p-nitrophenol. Adv. Mater. 2008, 20, 1523–1528.CrossRefGoogle Scholar
  11. [11]
    Yin, Y. D.; Lu, Y.; Sun, Y. G.; Xia, Y. N. Silver nanowires can be directly coated with amorphous silica to generate well-controlled coaxial nanocables of silver/silica. Nano Lett. 2002, 2, 427–430.CrossRefADSGoogle Scholar
  12. [12]
    Zhang, T. R.; Ge, J. P.; Hu, Y. X.; Zhang, Q.; Aloni, S.; Yin, Y. D. Formation of hollow silica colloids through a spontaneous dissolution-regrowth process. Angew. Chem. Int. Ed. 2008, 47, 5806–5811.CrossRefGoogle Scholar
  13. [13]
    Wang, L.; Zhao, W. J.; Tan, W. H. Bioconjugated silica nanoparticles: Development and applications. Nano Res. 2008, 1, 99–115.CrossRefGoogle Scholar
  14. [14]
    Zhang, T. R.; Zhang, Q.; Ge, J. P.; Goebl, J.; Sun, M. W.; Yan, Y. S.; Liu, Y. S.; Chang, C. L.; Guo, J. H.; Yin, Y. D. A self-templated route to hollow silica microspheres. J. Phys. Chem. C 2009, 113, 3168–3175.CrossRefGoogle Scholar
  15. [15]
    Ikeda, S.; Ikoma, Y.; Kobayashi, H.; Harada, T.; Torimoto, T.; Ohtani, B.; Matsumura, M. Encapsulation of titanium(IV) oxide particles in hollow silica for size-selective photocatalytic reactions. Chem. Comm. 2007, 3753–3755.Google Scholar
  16. [16]
    Hu, Y. X.; Ge, J. G.; Sun, Y. G.; Zhang, T. R.; Yin, Y. D. A self-templated approach to TiO2 microcapsules. Nano Lett. 2007, 7, 1832–1836.CrossRefPubMedADSGoogle Scholar
  17. [17]
    Deng, Y. H.; Qi, D. W.; Deng, C. H.; Zhang, X. M.; Zhao, D. Y. Superparamagnetic high-magnetization microspheres with an Fe3O4@SiO2 core and perpendicularly aligned mesoporous SiO2 shell for removal of microcystins. J. Am. Chem. Soc. 2008, 130, 28–29.CrossRefPubMedGoogle Scholar
  18. [18]
    Stöber, W.; Fink, A.; Bohn, E. Controlled growth of monodisperse silica spheres in micron size range. J. Colloid Interface Sci. 1968, 26, 62–69.CrossRefGoogle Scholar
  19. [19]
    Graf, C.; Dembski, S.; Hofmann, A.; Ruhl, E. A general method for the controlled embedding of nanoparticles in silica colloids. Langmuir 2006, 22, 5604–5610.CrossRefPubMedGoogle Scholar
  20. [20]
    Ge, J. P.; Zhang, Q.; Zhang, T. R.; Yin, Y. D. Core-satellite nanocomposite catalysts protected by a porous silica shell: Controllable reactivity, high stability, and magnetic recyclability. Angew. Chem. Int. Ed. 2008, 47, 8924–8928.CrossRefGoogle Scholar
  21. [21]
    Ohta, K. M.; Fuji, M.; Takei, T.; Chikazawa, M. Development of a simple method for the preparation of a silica gel based controlled delivery system with a high drug content. Eur. J. Pharm. Sci. 2005, 26, 87–96.CrossRefPubMedGoogle Scholar
  22. [22]
    Liu, R.; Zhao, X.; Wu, T.; Feng, P. Y. Tunable redox-responsive hybrid nanogated ensembles. J. Am. Chem. Soc. 2008, 130, 14418–14419.CrossRefPubMedGoogle Scholar

Copyright information

© Tsinghua University Press and Springer Berlin Heidelberg 2009

Authors and Affiliations

  • Qiao Zhang
    • 1
  • Jianping Ge
    • 1
  • James Goebl
    • 1
  • Yongxing Hu
    • 1
  • Zhenda Lu
    • 1
  • Yadong Yin
    • 1
  1. 1.Department of ChemistryUniversity of CaliforniaRiversideUSA

Personalised recommendations